The corrosion behavior of aluminum, copper, and iron in inhibited ethylene glycol-ASTM corrosive water solutions was evaluated in a laboratory loop under isothermal and heat-flux conditions for 1000 h at temperatures between 378 and 413 degrees K, in static autoclave tests at 450 degrees K for 500 h, and by potentiodynamic polarization measurements at temperatures between 298 and 348 degrees K. The effect of time, temperature, and ethylene glycol concentration of the heat-transfer fluid on the extent of inhibitor depletion was determined from analyses of the reserve alkalinity, pH, and inhibitor content of the solutions. The performance of an electrochemical sensor as a monitor of fluid quality was also evaluated. A heat flux of 0.4 to 1.0 kW/m sq. did not have a significant effect on the corrosion behavior of the various materials at temperatures between 378 and 413 degrees K. The corrosion rates of aluminum, copper, and iron in the 50 volume percent inhibited ethylene glycol-corrosive water solution decreased as a function of time during the 1000-h test. At 413 degrees K, the corrosion rate of copper was considerably higher than that of iron or aluminum at low flow velocity. Significant degradation of the fluid quality, as indicated by …

Cold-trap regeneration may be very important in future LMFBRs because of the expected high hydrogen source from the steam generators. This hydrogen precipitates as NaH in the cold trap and may fill the trap within one year of operation. Several methods of cold-trap regeneration were considered, but the simplest and least expensive appears to be decomposition of NaH under vacuum at elevated temperatures. Experiments were done to assess the feasibility of this method for cold-trap regeneration. Small-scale simulated cold traps (SCT) were loaded with NaH and NaH plus Na2O, and were heated both under vacuum and under a sweep gas at 100 kPa. The evolved hydrogen was converted to water by a CuO bed and collected in a weighing tube.

The branching fraction in the decay of the fission product ⁸⁵m-krypton⁸⁵m to the ground state ⁸⁵krypton (10.75 y) was measured relative to the total decay to both ⁸⁵krypton and ⁸⁵Rb. Samples of uranium-235 were highly irradiated in a high-flux reactor and dissolved. ⁸⁵Rb was measured by isotope-dilution mass spectrometry, and the ⁸⁵krypton was counted in GM tubes the counting efficiencies of which were calibrated with a standardized ⁸⁵krypton gas of known disintegration rate. The branching fraction measured with both a low-burnup sample and a high-burnup sample was 0.2160 +/- 0.0019, the largest error arising from the uncertainty in the caibration of the standardized gas.

A state-of-the-art review is presented on the corrosion and mechanical behavior of materials at elevated temperatures in coal-gasification environments. The gas atmosphere in coal-conversion processes are, in general, complex mixtures which contain sulfur-bearing components (hydrogen sulfide, SO2, and COS) as well as oxidants (carbon dioxide/carbon monoxide and water/hydrogen). The information developed over the last five years clearly shows sulfidation to be the major mode of material degradation in these environments. The corrosion behavior of structural materials in complex gas environments is examined to evaluate the interrelationships between gas chemistry, alloy chemistry, temperature, and pressure. Thermodynamic aspects of high-temperature corrosion processes that pertain to coal conversion are discussed, and kinetic data are used to compare the behavior of different commercial materials of interest. The influence of complex gas environments on the mechanical properties such as tensile, stress-rupture, and impact on selected alloys is presented. The data have been analyzed, wherever possible, to examine the role of environment on the property variation. The results from ongoing programs on char effects on corrosion and on alloy protection via coatings, cladding, and weld overlay are presented. Areas of additional research with particular emphasis on the development of a better understanding of corrosion processes in …

SACO is a fast-running computer code that simulates hypothetical accidents in liquid-metal fast breeder reactors to the point of permanent subcriticality or to the initiation of a prompt-critical excursion. In the tradition of the SAS codes each sub-assembly is modeled by a representative fuel pin with three distinct axial regions to simulate the blanket and core regions. However, analytic and integral models are used wherever possible to cut down the computing time and storage requirements. The physical models and basic equations are described in detail.

COMMIX-SA-1 is a three-dimensional, transient, single-phase, compressible-flow, component computer program for thermohydrodynamic analysis. It was developed for solar applications in general, and for analysis of thermocline storage tanks in particular. The conservation equations (in cylindrical coordinates) for mass, momentum, and energy are solved as an initial-boundary-value problem. The detailed numerical-solution procedure based on a modified ICE (Implicit Continuous-Fluid Eulerian) technique is described. A method for treating the singularity problem arising at the origin of a cylindrical-coordinate system is presented. In addition, the thermal interactions between fluid and structures (tank walls, baffles, etc.) are explicitly accounted for. Finally, the COMMIX-SA-1 code structure is delineated, and an input description and sample problems are presented.

The fraction of delayed neutrons beta in slow-neutron beams from a uranium-238 pulsed spallation neutron source is 0.0053 for 300 MeV protons. This measurement appears to be the first one of this quantity. The result indicates that, for most classes of measurements, the delayed-neutron background in time-of-flight instruments will be unimportant, and places constraints on the physics description of spallation targets. The measurement was performed at the prototype pulsed spallation neutron source, ZING-P', at Argonne National laboratory.

Nuclear material inventory verification techniques for large split-table type fast critical assemblies are being studied under this program. Emphasis has been given to techniques that minimize fuel handling in order to reduce facility down time and radiation exposure to the inventory team. The techniques studied include autoradiography, reactivity, and spectral index measurements.

PART 1: The effectiveness of a neutron well correlation counter (NWCC) and a random driver (RD) for plutonium-containing item assay and loss detection has been studied. The items were 4 in. x 2 in. x 1/4 in. stainless steel-clad metal plates and 6 in. x 3/8 in. stainless steel-clad oxide rods, each in two types of containment. PART 2: A neutron-counting/fuel-weighting system has been developed to provide the capability to assay the ZPR-6 and -9 plutonium fuel canisters rapidly and accurately. This system makes feasible the inline monitoring of fuel transfer from the storage vault to the fuel loading hoods and vice-versa. To exploit fully the system's potential, the equipment is intended to be used in conjunction with an on-line computer having a fuel and fuel-canister data base.

Nondestructive assay (NDA) methods, principally passive gamma measurements and active neutron interrogation, have been studied for their safeguards effectiveness and programmatic impact as tools for making inventories of highly enriched uranium fast critical assembly fuel plates. It was concluded that no NDA method is the sole answer to the safeguards problem, that each of those emphasized here has its place in an integrated safeguards system, and that each has minimum facility impact.

Large-scale efforts are in progress to develop advanced batteries for utility energy storage systems. Realization of the full benefits available from those systems requires development, not only of the batteries themselves, but also the ac/dc power converter, the bulk power interconnecting equipment, and the peripheral electric balance of plant equipment that integrate the battery/converter into a properly controlled and protected energy system. This study addresses these overall system aspects; although tailored to a 20-MW, 100-MWh lithium/sulfide battery system, the technology and concepts are applicable to any battery energy storage system.

Annual report of the Argonne National Laboratory Radiological and Environmental Research Division regarding activities related to molecular physics and chemistry. This report discusses the Section's work on the physics and chemistry of atoms, ions, and molecules - especially their interactions with external agents such as photons and electrons.

Quarterly report of the Argonne National Laboratory Chemical Engineering Division regarding activities related to properties and handling of radioactive materials, operation of nuclear reactors, and other relevant research.

Quarterly report of the Argonne National Laboratory Chemical Engineering Division regarding activities related to properties and handling of radioactive materials, operation of nuclear reactors, and other relevant research.

Quarterly report on the activities of the Argonne National Laboratory Materials Science Division regarding studies on ceramic (refractory) and metallic materials presently being used or intended for use in coal-conversion processes. The program entails research in the fields of nondestructive testing and failure analysis, together with studies of erosive wear, corrosion, and refractory degradation.

Quarterly report on the activities of the Argonne National Laboratory Materials Science Division regarding economical conversion of coal into clean and usable alternate fuels will be advanced through the use of durable materials systems. This program is designed to provide part of the materials information necessary for successful operation of coal-conversion systems.

Post-test examinations were conducted to determine failure mechanisms, electrode morphologies, and in-cell corrosion of cell components, and to recommend appropriate design changes for improved cell performance and reliability. The reactive electrode materials required the design and construction of a special metallographic glovebox facility. Combinations of macro- and microscopic examinations determined that electrical short circuits were the predominant causes of cell failure. The major short circuit mechanism was extrusion of active material from one electrode and its subsequent contact with the opposing electrode (opposite polarity). Other mechanisms for short circuits included metallic deposits across separators, metallic deposits across the feed-through insulator (electrolyte leakage and corrosion), equipment malfunctions, cell assembly difficulties, etc. Post-test examinations confirmed that the short circuits were of mechanical origin; appropriate design changes were, therefore, recommended. Extensive microscopic examinations were conducted on both negative and positive electrodes to determine the morphology. Agglomeration of Li-Al was observed in the negative electrodes of most multi-plate cells. Examinations showed that the sulfides in the positive electrode remained as discrete particles in an electrolyte matrix. Also discussed are the results of post-test examinations to determine the following: lithium gradients in the negative electrodes, electrode expansion, materials distribution, copper deposition within electrode separators of …

The fuel-pin modeling code LIFE-GCFR has been developed to predict the thermal, mechanical, and fission-gas behavior of a Gas-Cooled Fast Reactor (GCFR) fuel rod under normal operating conditions. It consists of three major components: thermal, mechanical, and fission-gas analysis. The thermal analysis includes calculations of coolant, cladding, and fuel temperature; fuel densification; pore migration; fuel grain growth; and plenum pressure. Fuel mechanical analysis includes thermal expansion, elasticity, creep, fission-product swelling, hot pressing, cracking, and crack healing of fuel; and thermal expansion, elasticity, creep, and irradiation-induced swelling of cladding. Fission-gas analysis simultaneously treats all major mechanisms thought to influence fission-gas behavior, which include bubble nucleation, resolution, diffusion, migration, and coalescence; temperature and temperature gradients; and fission-gas interaction with structural defects.

Quarterly report on the activities of the Argonne National Laboratory Materials Science Division regarding an examination of cores taken from the slag-refractory interface of seven refractories.

MINPACK-1 is a pack of FORTRAN subprograms for the numerical solution of nonlinear equations and nonlinear least-squares problems. This report provides an overview of the algorithms and software in the package, and includes the documentation and program listings.

A technique for incorporating automatic transformations into processes such as the application of inference rules, subsumption, and demodulation provides a mechanism for improving search strategies for theorem proving problems arising from the field of program verification. The incorporation of automatic transformations into the inference process can alter the search space for a given problem, and is particularly useful for problems having broad rather than deep proofs. The technique can also be used to permit the generation of inferences that might otherwise be blocked and to build some commutativity or associativity into the unification process. Appropriate choice of transformations, and new literal clashing and unification algorithms for applying them, showed significant improvement on several real problems according to several distinct criteria.

The results of an international comparison calculation of a large (1250 MWe) LMFBR benchmark model are presented and discussed. Eight reactor configurations were calculated. Parameters included with the comparison were: eigenvalue, k/sub infinity/, neutron balance data, breeding reaction rate ratios, reactivity worths, central control rod worth, regional sodium void reactivity, core Doppler and effective delayed neutron fraction. Ten countries participated in the comparison, and sixteen solutions were contributed. The discussion focuses on the variation in parameter values, the degree of consistency among the various parameters and solutions, and the identification of unexpected results. The results are displayed and discussed both by individual participants and by groupings of participants (e.g., results from adjusted data sets versus non-adjusted data sets).

A computational method is described for improving the accuracy of a given eigenvalue and its associated eigenvector, arrived at through a computation in a lower precision. The method to be described will increase the accuracy of the pair and do so at a relatively low cost. The technique used is similar to iterative refinement for the solution of a linear system; that is, through the factorization from the low-precision computation, an iterative algorithm is applied to increase the accuracy of the eigenpair. Extended precision arithmetic is used at critical points in the algorithm. The iterative algorithm requires O(n²) operations for each iteration.

Three types of metallic thermal insulation were investigated analytically and experimentally: multilayer reflective plates, multilayer honeycomb composite, and multilayer screens. Each type was subjected to evacuated and non-evacuated conditions, where thermal measurements were made to determine thermal-physical characteristics. A variation of the separation distance between adjacent reflective plates of multilayer reflective plates and multilayer screen insulation was also experimentally studied to reveal its significance. One configuration of the multilayer screen insulation was further selected to be examined in sodium and sodium oxide environments. The emissivity of Type 304 stainless steel used in comprising the insulation was measured by employing infrared technology. A comprehensive model was developed to describe the different proposed types of thermal insulation. Various modes of heat transfer inherent in each type of insulation were addressed and their relative importance compared. Provision was also made in the model to allow accurate simulation of possible sodium and sodium oxide contamination of the insulation. The thermal-radiation contribution to heat transfer in the temperature range of interest for LMFBR's was found to be moderate, and the suppression of natural convection within the insulation was vital in preserving its insulating properties. Experimental data were compared with the model and other published results. …