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GCFR shielding physics design and experimental program

Description: Analysis of the CORE 14 ThO/sub 2/ axial blanket experiment has produced the following results: The EIR and ORNL ENDF/B-4 data libraries produce similar central reaction rates (+-3% difference) except for the significantly higher /sup 232/Th (n, 2n) rate obtained using ORNL ENDF/B-4 data. Both libraries underpredict the central /sup 232/Th capture and fission rates with C/E values of 0.93 to 0.96 and 0.88 to 0.90 for C2/F9 and F2/F9, respectively. ENDF/B-5 thorium data produce significantly lower capture rates (-7%) and better fission and (n, 2n) rates (+5% and -6%, respectively) relative to ENDF/B-4 data. The central C/E values were insensitive to the theory and modeling approximations investigated; however, the weighting spectrum utilized in the cross section collapse must be properly matched to the calculated broad-group spectrum.
Date: January 1, 1980
Creator: Bartine, D.E. & Hamilton, C.J.
Partner: UNT Libraries Government Documents Department

Physical and chemical characteristics of Mt. St. Helens airborne debris

Description: Tephra and aerosols from the May 18, 1980 eruption of Mt. St. Helens, Washington were sampled in the lower stratosphere with a WB-57F aircraft. The main body of the plume was intercepted over western Kansas on May 20, 48 hours after the eruption, at an altitude of 15.2 km. Concentrations on filter samples were 26 ng of SO/sub 4//g of air and 579 ng of ash/g of air. Angular glass pyroclasts ranged in size from 0.5 to 10 ..mu..m, with a mean grain size of 2 ..mu..m. Samples collected at altitudes of 16.7 and 12.5 km had only traces of SO/sub 4/ and ash. A second flight was flown, 72 hours after the eruption, on May 21. From north Texas to central Wyoming, at an altitude of 15.2 km, < 0.5 to 38 ng of ash/g of air and 1.0 to 2.2 ng of SO/sub 4//g of air were sampled. At an altitude of 18.3 km, from central Wyoming to NW New Mexico, the plume density and character were variable. Glassy pyroclasts similar to those sampled on the first flight range in size from 0.5 to 4 ..mu..m dia. Trace element analysis revealed some volatile element enrichment, but far less than previously observed in the plume from St. Augustine Volcano, 1976. Values of /sup 210/Po//sup 210/Pb were 0.7 to 1.32 comparable to the secular equilibrium value of 1.0 and far less than ratios previously reported by Lambert.
Date: January 1, 1980
Creator: Sedlacek, W.A.; Heiken, G.H.; Mroz, E.J.; Gladney, E.S.; Perrin, D.R.; Leifer, R. et al.
Partner: UNT Libraries Government Documents Department

Mound Facility activities in chemical and physical research: July-December 1979

Description: Research is reported in the following fields: isotope separation (Ar, C, He, Kr, Ne, O, Xe), low-temperature research (H intermolecular potential functions, gas analysis in trennschaukel), separation chemistry (/sup 229/Th, /sup 231/Pa, /sup 230/Th, /sup 234/U), separation research (liquid thermal diffusion, Ca isotope separation, molecular beam scattering, mutual diffusion of noble gas mixtures, lithium chemical exchange with cryptands), and calculations in plutonium chemistry (algorithms, valence in natural water). (DLC)
Date: June 18, 1980
Partner: UNT Libraries Government Documents Department

Principles and characteristics of surface radon and helium techniques used in uranium exploration

Description: Studies were carried out to determine the nature of some of the surface radon and helium techniques used for uranium exploration. By performing radon and helium measurements at three sites with differing geology and accessibility, we were able to examine the constraints on the features determined. The sites are the Red Desert in south central Wyoming, Copper Mountain in central Wyoming, and Spokane Mountain in eastern Washington. The radon techniques employed were: zinc sulfide detectors, an ionization chamber, alpha track detectors, thermoluminescence detectors, charcoal canisters, and the partial extraction of lead-210 from soil samples. Helium was measured in soil-gas samples, soil gas from collectors, and soil samples. The ratio helium-4/argon-36 was measured in soil gas.
Date: September 1, 1980
Creator: Pacer, J.C. & Czarnecki, R.F.
Partner: UNT Libraries Government Documents Department

Industrial safety and applied health physics. Annual report, 1979

Description: In connection with personnel monitoring, there were no external or internal exposures to personnel which exceeded the standards for radiation protection as defined in DOE Manual Chapter 0524. Only 55 employees received whole-body dose equivalent of one rem or greater. The highest whole-body dose equivalent to an employee was 2.8 rem. The highest internal exposure was less than one-half of a maximum permissible dose for any calendar quarter. During 1979, 57 portable health physics instruments were added to the inventory and 75 retired. The total number in service on January 1, 1979, was 977. With regards to environmental monitoring, there were no releases of gaseous waste from the Laboratory which were of a level that required an incident report to DOE. There were no releases of liquid radioactive waste from the Laboratory which were of a level that required an incident report to DOE. Soil samples were collected at all perimeter and remote monitoring stations and analyzed for eleven radionuclides including plutonium and uranium. Plutonium-239 content ranged from 0.01 to 0.06 pCi/g, and the uranium-235 content ranged from 0.01 to 0.05 pCi/g. Grass samples were collected at all perimeter and remote monitoring stations and analyzed for twelve radionuclides including plutonium and uranium. Plutonium-239 content ranged from 0.001 to 0.010 pCi/g, and uranium-235 content ranged from 0.001 to 0.010 pCi/g. Two radiation incidents involving radioactive materials were recorded during 1979. This compares with 14 incidents in 1978. (ERB)
Date: September 1, 1980
Partner: UNT Libraries Government Documents Department

Radiochemical analyses of samples from beneath a solid radioactive waste disposal pit at Los Alamos, New Mexico

Description: Solid radioactive wastes are disposed of by burial in pits excavated in rhyolite tuff at the Los Alamos Scientific Laboratory (LASL). Contaminants in the waste include fission products, uranium, and transuranic elements. In 1976, horizontal core holes were drilled beneath a waste disposal pit that was used from 1963 to 1966. Samples of the core were analyzed for gross alpha, gross beta, total uranium, /sup 90/Sr, /sup 137/Cs, /sup 238/Pu, /sup 239/ /sup 240/Pu, and /sup 241/Am. The measured gross alpha, gross beta, and uranium concentrations were above minimum detection limits; concentrations of the remaining radionuclides, all of which are man-made isotopes, were below the minimum detection limits. Statistical comparisons were made of the gross alpha, gross beta, and uranium data to identify any significant variations from natural concentrations in the tuff. The comparisons demonstrated that none of the radioactivity detected in the samples can be attributed to migration from the disposal pit.
Date: June 1, 1980
Creator: Purtymun, W.D.; Rogers, M.A. & Wheeler, M.L.
Partner: UNT Libraries Government Documents Department

Status of /sup 241/Am recovery and purification at Los Alamos Scientific Laboratory

Description: Americium recovery was initiated at Los Alamos Scientific Laboratory (LASL) in the late 1940's. The early procedures separated gram quantities of americium from large amounts of impurities including plutonium and the rare earths. Ion exchange procedures were developed for further purification. Until recently, no routine processing of americium has been done at LASL for several years. The increasing demand for americium in oil-well logging instruments and other uses led LASL to develop and install a process to recover larger quantities of americium. The LASL process was developed around the chemistry of americium that had been elucidated both at LASL and at other facilities. Presently, the americium feed is obtained as a by-product from a plutonium purification process at the new plutonium facility at LASL. This feed filtrate from a peroxide precipitation process is precipitated as a slurry of hydroxides, filtered, dissolved in nitric acid, and passed through an anion exchange column to remove any residual plutonium. The americium, contained in the effluent, is precipitated as the oxalate and calcined to the oxide. Americium is also available in other highly salted acidic process streams. These should lend themselves to solvent extraction. Developmental work has been promising, and a dibutyl butyl phosphate-kerosene extraction process is being brought on-line.
Date: January 1, 1980
Creator: Ramsey, H.D.; Clifton, D.G.; Hayter, S.W.; Penneman, R.A. & Christensen, E.L.
Partner: UNT Libraries Government Documents Department

Chromatographic cation exchange separation of decigram quantities of californium and other transplutonium elements

Description: Decigram quantities of highly radioactive transplutonium elements are routinely partitioned at TRU by chromatographic elution from cation resin using AHIB eluent. By using two high-pressure ion exchange columns, a small one for the initial loading of the feed and a large one for the elution, batch runs containing up to 200 mg of /sup 252/Cf can be made in about 5 hours (2 hours to load the feed and 3 hours for the elution). The number of effluent product fractions and the amount of actinides that must be collected in intermediate fractions are minimized by monitoring response from a flow-through alpha-detector. This process has been reliable and relatively easy to operate, and will continue to be used for partitioning transplutonium elements at TRU.
Date: January 1, 1980
Creator: Benker, D.E.; Chattin, F.R.; Collins, E.D.; Knauer, J.B.; Orr, P.B.; Ross, R.G. et al.
Partner: UNT Libraries Government Documents Department

Experience in the separation and purification of transplutonium elements in the transuranium processing plant at the Oak Ridge National Laboratory

Description: Since 1966, TRU has been the main center of production for transcurium elements in the US, producing 460 mg /sup 249/Bk, 4 g /sup 252/Cf, 18 mg /sup 253/Es, and 10 pg /sup 257/Fm. During the 14 years operation, 39 chemical processing campaigns were conducted to process 265 HFIR targets and 195 SRP production reactor targets. (DLC)
Date: January 1, 1980
Creator: King, L.J.; Bigelow, J.E. & Collins, E.D.
Partner: UNT Libraries Government Documents Department

Analysis of heat and mass transfer in sub-seabed disposal of nuclear waste

Description: A mathematical basis is developed for the prediction of thermal and radionuclide transport in marine sediments. The theory is applied to the study of radioactive waste disposal by emplacement, in specially designed containers, well below the sediment/water interface. Numerical results are obtained for a specified model problem through use of two computer programs designed primarily for the analysis of waste disposal problems. One program (MARIAH) provides descriptions of the temperature and velocity fields induced by the presence of a container of thermally active nuclear waste. A second program (IONMIG), which utilizes the results of the thermal analysis, is used to provide predictions for the migration of four representative radionuclides: /sup 239/Pu, /sup 137/Cs, /sup 129/I, and /sup 99/Tc.
Date: January 1, 1980
Creator: Hickox, C. E.; Gartling, D. K.; McVey, D. F.; Russo, A. J. & Nuttall, H. E.
Partner: UNT Libraries Government Documents Department

Modeling study of gaseous Rn-222, Xe-133, and He-4 for uranium exploration

Description: This work presents one-dimensional mathematical models to simulate the transport of gaseous radon-222 (Rn-222), xenon-133 (Xe-133), and helium-4 (He-4) away from uranium ore deposits. The resulting concentrations of indicator nuclides in the overburden are used to infer the detectability of ore deposits by emanation methods. In the case of homogeneous, non-radioactive formations, Rn-222 and some of its daughter products are calculated to be detectable at distances of several tens of meters from a planar uranium ore deposit (1 m tickness, 0.6% U/sub 3/O/sub 8/, 20% emanation). Models of He-4 diffuson in rock yield highly uncertain results because measurements of diffusion coefficients in actual rock types are lacking and because the flux of helium from deep within the earth is generally unknown. Comparisons of model results to field data suggest that He-4 diffusion coefficients of 10/sup -4/ to 10/sup -5/ cm/sup 2//sec are appropriate. It is speculated that moisture in the rock column could reduce the coefficient significantly compared to the dry-soil case. Inhomogeneity in rock formations is simulated by a multiple-layer model. A comparison of fluorometric uranium data to gamma spectra measurements suggests the migration and deposition of Ra-226 near the water table. Modeling results are improved when this process is taken into account. A constant soil gas velocity of 1 x 10/sup -4/ cm/sec causes indicator concentrations to change by several orders of magnitude. If steady upward soil gas motion exists in nature, the detectability of uranium ore by emanation methods will be significantly different from that indicated by pure diffusion models. Barometric influences on gas transport are simulated by time-dependent numerical models.
Date: January 1, 1980
Creator: Jeter, H.W.
Partner: UNT Libraries Government Documents Department

Thermodynamic study of the MWG system/components and measurement of the oxygen partial pressure in the heat source capsule

Description: A thermodynamic study of the Milliwatt Generator heat source capsule was performed to determine the effects of the oxide fuel on container materials at elevated temperatures in order to evaluate the factors affecting embrittlement of T-111 alloy. The study indicates that relatively slow oxidation of the T-111 of the capsule occurs during pretreatment. Yttrium added to the /sup 238/PuO/sub 2/ fuel charge is functioning in its designed role as an oxygen getter and is stabilizing at an O/Pu ratio of 1.75. The free energy of formation of hafnium oxide has been measured and found to be -70632 cal/mole; this suggests that the ability of hafnium to strongly function as an oxygen getter may be largely determined by the kinetics, and the free energy may play a lesser role.
Date: June 23, 1980
Creator: David, D.J.
Partner: UNT Libraries Government Documents Department

Radon release and dispersion from an open pit uranium mine

Description: Radon-222 flux from representative sections of the United Nuclear St. Anthony open-pit mine complex was measured. The collected radon was adsorbed on activated charcoal and the radon activity was measured by gamma spectroscopy. System design, calibration, and the procedure to determine radon flux density (pCi/m/sup 2/.s) are described. A continuous series of radon flux densities were measured over a 5-month period at a control point in the mine. The average flux density at the control point was 1.9 pCi/m/sup 2/.s. A close correlation between radon flux density variations and changes in barometric pressure was observed by a comparison of meteorological data and average daily radon flux density measured at the control point. The release rate from each section of the mine was calculated from the average radon flux density and the area of the section, as determined from enlarged aerial photographs. The average radon flux density for eight locations over the ore-bearing section was 7.3 pCi/m/sup 2/.s. The average flux density for four locations over undisturbed topsoil was 0.17 pCi/m/sup 2/.s. The average Ra-226 content of ten samples taken from the ore-bearing region was 102 pCi/g ore. The ratio of radon flux density to radium content (specific flux) was 0.072. The release rate from the entire St. Anthony open pit was determined to be 3.5 x 10/sup 5/ pCi/s. This rate is comparable to the natural release of radon from one square mile of undisturbed topsoil. 16 refs., 31 figs., 11 tabs.
Date: June 1, 1980
Creator: Kisieleski, W.E.
Partner: UNT Libraries Government Documents Department

Residential radon daughter monitor based on alpha spectroscopy

Description: The radioactive daughters of radon-222 pose a serious indoor air quality problem in some circumstances. A technique for measuring the concentrations of these radioisotopes in air is presented. The method involves drawing air through a filter; then, for two time intervals after sampling, counting the alpha decays from polonium-218 and polonium-214 on the filter. The time intervals are optimized to yield the maximum resolution between the individual daughter concentrations. For a total measurement time of 50 minutes, individual daughter concentrations of 1.0 nanocuries per cubic meter are measured with an uncertainty of 20%. A prototype of a field monitor based on this technique is described, as is a field test in which the prototype was used to measure radon daughter concentrations as a function of ventilation conditions in an energy-efficient house.
Date: May 1, 1980
Creator: Nazaroff, W.W.
Partner: UNT Libraries Government Documents Department

Radiological survey of the inactive uranium-mill tailings at Falls City, Texas

Description: Results of a radiological survey conducted at the Falls City, Texas, site in July 1976 are presented. There are seven partial to fully stabilized tailings piles, and an overburden pile from an open-pit mine. Above ground gamma-ray exposure rate measurements show moderate levels of contamination throughout the area with a maximum exposure rate of 500 ..mu..R/hr above tailings pile 2. The average exposure rate over the different areas varied from 14 ..mu..R/hr over the southwest end of tailings pile 7 to 207 ..mu..R/hr over the northeast end of the same pile. Analyses of surface soil and dry-wash sediment samples, as well as calculations of subsurface /sup 226/Ra distribution, serve to define the spread of tailings around the area. Water erosion of the tailings is evident, but, because of abundant growth of vegetation on the tailings piles, wind erosion probably is not a major problem.
Date: October 1, 1980
Creator: Haywood, F.F.; Christian, D.J.; Loy, E.T.; Lorenzo, D. & Ellis, B.S.
Partner: UNT Libraries Government Documents Department

Radiological survey of the radioactive sands and residues at Lowman, Idaho

Description: No uranium ore milling was performed at the Lowman site, which is located approximately 0.8 km northeast of the town of Lowman, Idaho. Nevertheless, approximately 80,000 metric tons of radioactive sands and residues from upgrading of heavy minerals by physical processing methods remain on the site grounds. Measurements of external gamma radiation 1 m above the surface showed exposure rates up to 2.4 mR/hr on site, but the exposure rate off site quickly dropped to the background level in all directions. Analysis of surface soil and sediment samples for /sup 226/Ra and /sup 232/Th indicated a limited spread of radioactive material.
Date: August 1, 1980
Creator: Haywood, F.F.; Burden, J.E.; Ellis, B.S.; Loy, E.T. & Shinpaugh, W.H.
Partner: UNT Libraries Government Documents Department

Transuranic concentrations in reef and pelagic fish from the Marshall Islands. [/sup 239/Pu, /sup 240/Pu]

Description: Concentrations of /sup 239 + 240/Pu are reported in tissues of several species of reef and pelagic fish caught at 14 different atolls in the northern Marshall Islands. Several regularities that are species dependent are evident in the distribution of /sup 239 + 240/Pu among different body tissues. Concentrations in liver always exceeded those in bone and concentrations were lowest in the muscle of all fish analyzed. A progressive discrimination against /sup 239 + 240/Pu was observed at successive trophic levels at all atolls except Bikini and Enewetak, where it was difficult to conclude if any real difference exists between the average concentration factor for /sup 239 + 240/Pu among all fish, which include bottom feeding and grazing herbivores, bottom feeding carnivores, and pelagic carnivores from different atoll locations. The average concentration of /sup 239 + 240/Pu in the muscle of surgeonfish from Bikini and Enewetak was not significantly different from the average concentrations determined in these fish at the other, lesser contaminated atolls. Concentrations among all 3rd, 4th, and 5th trophic level species are highest at Bikini where higher environmental concentrations are found. The reasons for the anomalously low concentrations in herbivores from Bikini and Enewetak are not known.
Date: September 1, 1980
Creator: Noshkin, V.E.; Eagle, R.J.; Wong, K.M. & Jokela, T.A.
Partner: UNT Libraries Government Documents Department

Environmental radiation safety: source term modification by soil aerosols. Interim report

Description: The goal of this project is to provide information useful in estimating hazards related to the use of a pure refractory oxide of /sup 238/Pu as a power source in some of the space vehicles to be launched during the next few years. Although the sources are designed and built to withstand re-entry into the earth's atmosphere, and to impact with the earth's surface without releasing any plutonium, the possibility that such an event might produce aerosols composed of soil and /sup 238/PuO/sub 2/ cannot be absolutely excluded. This report presents the results of our most recent efforts to measure the degree to which the plutonium aerosol source term might be modified in a terrestrial environment. The five experiments described represent our best effort to use the original experimental design to study the change in the size distribution and concentration of a /sup 238/PuO/sub 2/ aerosol due to coagulation with an aerosol of clay or sandy loam soil.
Date: August 1, 1980
Creator: Moss, O.R.; Allen, M.D.; Rossignol, E.J. & Cannon, W.C.
Partner: UNT Libraries Government Documents Department

Waste isolation safety assessment program. Task 4. Third contractor information meeting

Description: The Contractor Information Meeting (October 14 to 17, 1979) was part of the FY-1979 effort of Task 4 of the Waste Isolation Safety Assessment Program (WISAP): Sorption/Desorption Analysis. The objectives of this task are to: evaluate sorption/desorption measurement methods and develop a standardized measurement procedure; produce a generic data bank of nuclide-geologic interactions using a wide variety of geologic media and groundwaters; perform statistical analysis and synthesis of these data; perform validation studies to compare short-term laboratory studies to long-term in situ behavior; develop a fundamental understanding of sorption/desorption processes; produce x-ray and gamma-emitting isotopes suitable for the study of actinides at tracer concentrations; disseminate resulting information to the international technical community; and provide input data support for repository safety assessment. Conference participants included those subcontracted to WISAP Task 4, representatives and independent subcontractors to the Office of Nuclear Waste Isolation, representatives from other waste disposal programs, and experts in the area of waste/geologic media interaction. Since the meeting, WISAP has been divided into two programs: Assessment of Effectiveness of Geologic Isolation Systems (AEGIS) (modeling efforts) and Waste/Rock Interactions Technology (WRIT) (experimental work). The WRIT program encompasses the work conducted under Task 4. This report contains the information presented at the Task 4, Third Contractor Information Meeting. Technical Reports from the subcontractors, as well as Pacific Northwest Laboratory (PNL), are provided along with transcripts of the question-and-answer sessions. The agenda and abstracts of the presentations are also included. Appendix A is a list of the participants. Appendix B gives an overview of the WRIT program and details the WRIT work breakdown structure for 1980.
Date: June 1, 1980
Partner: UNT Libraries Government Documents Department

Prediction of the migration of several radionuclides in ocean sediment with the computer code IONMIG: a preliminary report

Description: A computer code, IONMIG, which is used to calculate the far-field transport of radionuclides through ocean sediment by diffusion and convection is described. The code uses a two-dimensional, axisymmetric, explicit finite difference formulation. Preliminary results for several species (Cs, Pu, I, Tc) are given.
Date: May 1, 1980
Creator: Russo, A.J.
Partner: UNT Libraries Government Documents Department

Californium-252 encapsulation at the Savannah River Laboratory

Description: More than 1 g of the neutron-emitting isotope californium-252 has been encapsulated at SRL for worldwide medical, industrial, and research uses. Bulk sales packages have been prepared for the USDOE sales program since 1971. Doubly-encapsulated sources have been prepared for USDOE's market evaluation program since 1968. Californium-252 sources for loan and sales packages satisfy the criteria for Special Form Radioactive Material. Encapsulation is performed in special neutron-shielded containment facilities at SRL. Development of improved source and shipping package designs and processes is continuing. 17 figures.
Date: January 1, 1980
Creator: Boulogne, A.R.
Partner: UNT Libraries Government Documents Department

Covalency of Neptunium(IV) organometallics from /sup 237/Np Moessbauer spectra

Description: The isomer shifts in /sup 237/Np Moessbauer spectra arise from the shielding of neptunium's 6s orbitals by the inner 5f orbitals. In covalent bonding, ligand contributions to the 5f electron density increase the shielding, and the /sup 237/Np isomer shift reflects differences in bond character among covalently bonded ligands. The large difference in isomer shift (3.8 cm/sec) between ionic Np(IV) and Np(III) compounds permits a good determination of ligand bonding differences in Np(IV) organometallic compounds. The Moessbauer spectra for about 20 Np(IV) organometallic compounds, principally cyclopentadienyl (Cp) compounds of the general composition Cp/sub x/Np chi/sub 4-x/ (x = 1,2,3; chi = Cl, BH/sub 4/, /sup n/Bu, Ph, OR, acac), show both the differences in sigma bonding among the chi ligands, as well as the covalent effect of the Cp ligands.
Date: January 1, 1980
Creator: Karraker, D.G.
Partner: UNT Libraries Government Documents Department

Recovery of americium-241 from aged plutonium metal

Description: After separation and purification, both actinides were precipitated as oxalates and calcined. A large-scale process was developed using dissolution, separation, purification, precipitation, and calcination. Efforts were made to control corrosion, to avoid product contamination, to keep the volume of process and waste solutions manageable, and to denitrate solutions with formic acid. The Multipurpose Processing Facility (MPPF), designed for recovery of transplutonium isotopes, was used for the first time for the precipitation and calcination of americium. Also, for the first time,, large-scale formic acid denitration was performed in a canyon vessel at SRP.
Date: January 1, 1980
Creator: Gray, L W; Burney, G A; Reilly, T A; Wilson, T W & McKibben, J M
Partner: UNT Libraries Government Documents Department

/sup 238/Pu fuel form processes bimonthly report, May-June 1979

Description: Progress in the Savannah River /sup 238/Pu Fuel Form Program is summarized. Full-scale fabrication tests of General-Purpose Heat Source (GPHS) fuel forms continued in the SRL Plutonium Experimental Facility (PEF) as four additional pellets (GPHS Pellets 5-8) were hot pressed. GPHS pellets fabricated by the reference process were dimensionally and structurally stable during and after final heat treatment. Microstructural studies confirmed that centerline GPHS process conditions produce pellets with a homogeneous microstructure and a uniform density. Because of the potential for excessive metal creep in existing furnace racks, the racks were considered unacceptable for GPHS fuel production in the PuFF. To eliminate metal creep, racks containing some ceramic components were designed to operate at 1600/sup 0/C in an oxygen atmosphere for more than 100 h. The four-key variables previously identified (shard sintering temperature, hot press load, hot press temperature, and load ramp) were found to correlate with production sphere fracture tendency and bulk density.
Date: February 1, 1980
Partner: UNT Libraries Government Documents Department