Results are reported in a program to design, synthesize, and evaluate polycyclic host organic compounds for their abilities to complex and lipophilize guest metal ions. Work during the reporting period was devoted to synthesis and study of cyclohexametaphenylenes and cyclic phosphine oxides. (JRD)

The validation of a service life of 20 years for low-cost photovoltaic arrays must be accomplished through accelerated life-prediction tests. A methodology for such tests has been developed in a preceding study. The results discussed consist of the initial identification and assessment of all known measurement techniques and instruments that might be used in these life-prediction tests. Array failure modes, relevant materials property changes, and primary degradation mechanisms are discussed as a prerequisite to identifying suitable measurement techniques and instruments. Candidate techniques and instruments are identified on the basis of extensive reviews of published and unpublished information. These methods are organized in six measurement categories--chemical, electrical, optical, thermal, mechanical, and ''other physicals''. Using specified evaluation criteria, the most promising techniques and instruments for use in life-prediction tests of arrays are then selected. These recommended techniques and their characteristics are described. Recommendations are made regarding establishment of the adequacy, particularly with respect to precision, of the more fully developed techniques for this application, and regarding the experimental evaluation of promising developmental techniques. Measurement needs not satisfied by presently available techniques/instruments are also identified.

A detailed economic evaluation is presented of several EFG ribbon growth technology scenarios using the ''SAMICS'' interim price estimation guidelines. It is concluded that the growth of 10 ribbons from a double five ribbon furnace of the general type represented by the existing Machine 3A would meet the requirements of producing ribbon at a price below $20/m/sup 2/ the 1986 goal. The technology requirements are that one operator can operate 2 of the 5 ribbon growth stations in which each ribbon grows at a speed of 7.5 cm/min and is also 7.5 cm wide. The machines also would have to achieve a duty cycle of 67% at minimum and yields above 75%. Finally, silicon must be available at $10 to approximately $25/kg, depending on the yield assumed. These conclusions are the final results of the economic analysis. The progress towards the growth of 7.5 cm wide ribbon at 7.5 cm/min is discussed. Also, fluid flow phenomena have been investigated and it is shown that by utilization of such phenomena the impurity distribution in the ribbon may be manipulated to a significant extent. Also, using a somewhat novel ''EBIC'' technique it was demonstrated that the internal grain structure found previously in …

Base properties have been determined for A387-74A-Gr. 22-Cl. 2 steel at various temperatures in inert environments. Tests have been completed to monitor the actual stress level as a function of exposure time in tensile samples loaded in pre-compressed rings. Samples were exposed under various stress levels at 900/sup 0/F to determine the amount of creep during the 168 hour exposures. Results of all exposure tests (including samples under load during exposure with and without creep, in inert gas) revealed that no degradation of ambient temperature mechanical properties occurred.