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A Class 1 review of the thermal analysis of the LOFT Steam Generator and of the transient thermal analysis of LOFT steam generator thermal well was made to confirm compliance of the analyses with the LOFT Technical Specifications, with the LOFT integral test system - preliminary component design description for the steam generator, and with Appendix C of ANC Specification 60139. Included in this review is an examination of the thermal transients and conditions to insure adequate conservatism in analyzed conditions and transients to which the LOFT Steam Generator (including thermal well) might be exposed while in service at the LOFT reactor facility. Also, a review of the thermal code used was made to check for its applicability to these analyses.

The present project involves the second phase of research on a new concept in coal-water fuel (CWF) atomization that is applicable to burning in small combustors. It is intended to address the most important problem associated with CWF combustion; i.e., production of small spray droplets in an efficient manner by an atomization device. Phase 1 of this work was successfully completed with the development of an opposed-jet atomizer that met the goals of the first contract. Performance as a function of operating conditions was measured, and the technical feasibility of the device established in the Atlantic Research Atomization Test Facility employing a Malvern Particle Size Analyzer. Testing then proceeded to a combustion stage in a test furnace at a firing rate of 0.5 to 1.5 MMBtu/H.

In 1960, Hansen analyzed the problem of assembling fissionable material in the presence of a weak neutron source. Using point kinetics, he derived the weak source condition and analyzed the consequences of delayed initiation during ramp reactivity additions. Although not clearly stated in Hansen`s work, the neutron source strength that appears in the weak source condition actually corresponds to the equivalent, fundamental-mode source. In this work, they describe the concept of an equivalent, fundamental-mode source and they derive a deterministic expression for a factor, g*, that converts any arbitrary source distribution to an equivalent, fundamental-mode source. They also demonstrate a simplified method for calculating g* in subcritical systems. And finally, they present a new experimental method that can be employed to measure the equivalent, fundamental-mode source strength in a multiplying assembly. They demonstrate the method on the zero-power, XIX-1 assembly at the Fast Critical Assembly (FCA) Facility, Japan Atomic Energy Research Institute (JAERI).

{sup 13}C-carbon black substituted composite LiNi{sub 0.8}Co{sub 0.15}Al{sub 0.05}O{sub 2} cathodes were tested in model electrochemical cells to monitor qualitatively and quantitatively carbon additive(s) distribution changes within tested cells and establish possible links with other detrimental phenomena. Raman qualitative and semi-quantitative analysis of {sup 13}C in the cell components was carried out to trace the possible carbon rearrangement/movement in the cell. Small amounts of cathode carbon additives were found trapped in the separator, at the surface of Li-foil anode, in the electrolyte. The structure of the carried away carbon particles was highly amorphous unlike the original {sup 12}C graphite and {sup 13}C carbon black additives. The role of the carbon additive, the mechanism of carbon retreat in composite cathodes and its correlation with the increase of the cathode interfacial charge-transfer impedance, which accounts for the observed cell power and capacity loss is investigated and discussed.

Two scenarios were examined for small-scale electricity production from biomass using a gasifier/fuel cell system. In one case, a stand-alone BCL/FERC gasifier is used to produce synthesis gas that is reformed and distributed through a pipeline network to individual phosphoric acid fuel cells. In the second design, the gasifier is integrated with a molten carbonate fuel cell stack and a steam bottoming cycle. In both cases, the gasifiers are fed the same amount of material, with the integrated system producing 4 MW of electricity, and the stand-alone design generating 2 MW of electricity.

The Solar Energy Research Institute has conducted a limited sensitivity analysis on a System for Projecting the Utilization of Renewable Resources (SPURR). The study utilized the Domestic Policy Review scenario for SPURR agricultural and industrial process heat and utility market sectors. This sensitivity analysis determines whether variations in solar system capital cost, operation and maintenance cost, and fuel cost (biomass only) correlate with intuitive expectations. The results of this effort contribute to a much larger issue: validation of SPURR. Such a study has practical applications for engineering improvements in solar technologies and is useful as a planning tool in the R and D allocation process.

This report describes work under Phase II of a Photovoltaic Manufacturing Technology project to conduct laboratory problem definition with an emphasis on controlled aging studies to evaluate the influence of various compositional, processing, and operating parameters on ethylene vinyl acetate (EVA) discoloration. In support of future accelerated UV aging studies (AAS) of coupon-sized EVA laminates, an Atlas xenon arc Ci35A Weather-Ometer was procured, installed, and calibrated for temperature and irradiance. In preparing for the AAS studies, UV-visible spectroscopy measurements were performed on various types of low-iron glass, representive of materials used for module superstrates. It was discovered that the transmission spectra of some of the grades in the UV region from 250 to 400 nm was significantly different. Older grades of Solatex and solite, and StarPhire 'cut off' well below 290 nm, while newer grades of Solatex and Solite, and StarPhire and Airphire greatly reduce the UV transmittance between 280 and 330 nm. Controlled aging studies are presently underway at 0.55 W/m2, 340 nm, and 100 degrees C, and we expect comparative data on yellowing to be available soon.

This document is the final report of work on a project concerned with the fragmentation of char particles during pulverized coal combustion that was conducted at the High Temperature Gasdynamics Laboratory at Stanford University, Stanford, California. The project is intended to satisfy, in part, PETC`s research efforts to understand the chemical and physical processes that govern coal combustion. The overall objectives of the project were: (1) to characterize the fragmentation events as a function of combustion environment, (2) to characterize fragmentation with respect to particle porosity and mineral loadings, (3) to assess overall mass loss rates with respect to particle fragmentation, and (4) to quantify the impact of fragmentation on unburned carbon in ash. The knowledge obtained during the course of this project can be used to predict accurately the overall mass loss rates of coals based on both the physical and chemical characteristics of their chars. The work provides a means of assessing reasons for unburned carbon in the ash of coal fired boilers and furnaces.