Four Fe-based superalloys, JBK-75, Incoloy 903, Incoloy 905, and Incoloy 909 were evaluated as tube materials for ICCS Nb/sub 3/Sn superconductors. Evaluation consisted of 4-K tensile and elastic-plastic fracture-toughness testing, and a microstructural characterization of unwelded and autogenously gas-tungsten-arc welded sheet given a simulated postweld processing treatment of 15% cold reduction by rolling followed by a Nb/sub 3/Sn-reaction heat treatment of 96 hours at 700/sup 0/C plus 48 hours at 730/sup 0/C. Results indicate that JBK-75 and Incoloy 903 showed satisfactory combinations of strength and toughness for ICCS tube use requiring long Nb/sub 3/Sn-reaction heat treatments. Incoloy 905 welds and 909 showed unacceptable fracture toughness. Results are discussed in terms of microstructural changes caused by the extended Nb/sub 3/Sn-reaction heat treatment.

After a brief introduction to the present state of art of nuclear beta-decay studies in astrophysics, we report our recent work on the long-standing /sup 99/Tc problem. Having combined a detailed study of the recurrent He-shell thermal-pulse, third dredge-up episodes in a 2.25 M/sub solar/ star and an s-process network calculation, we show that a substantial amount of /sup 99/Tc can be produced by the s-process and can survive to be dredged up to the stellar surface. We stress that the factual observation of /sup 99/Tc at the surface of certain stars does not necessarily preclude the /sup 22/Ne(..cap alpha..,n)/sup 25/Mg reaction from remaining as the neutron source for the s-process. The calculated surface abundances of /sup 99/Tc and elements with neighboring atomic numbers are compared with observations. 43 refs., 5 figs.

The Nova laser, completed in December 1984 at Lawrence Livermore National Laboratory, is being used to conduct inertial confinement fusion experiments. It is capable of focusing more than 100 kJ of energy on small fusion targets. This paper discusses an optical system called the target plane imager that is used during the beam alignment phase of these experiments. The TPI includes a three meter long periscope with a wide field of view, F/3 objective. The telescope relays images of the target focal plane to viewing optics and a video sensor located outside the target chamber. Operation of the system is possible at three wavelengths: 1.05..mu.., 0.527..mu.., and 0.351..mu... These are the three wavelengths at which the ten Nova laser beams can irradiate targets. Both nearfield and farfield images of the ten beams can be viewed with the TPI. This instrument is used to properly align the laser to the target before each target irradiation.

This paper discusses the two components of the facilitative setting that are important for group formation. The first component, the ideological component, provides the basic ideas that are adopted by the emerging group. The ideological setting for group formation is produced by such things as antinuclear news coverage and concentration of news stories on hazardous waste problems, on ideas concerning the credibility of the federal government, and on the pervasivensee of ideas about general environmental problems. The organizational component of the facilitative setting provides such things as leadership ability, flexible time, resources, and experience. These are important for providing people, organization, and money to achieve group goals. By and large, the conditions conducive to group formation, growth, and survival are outside the control of decision-makers. Agencies and project sponsors are currently caught in a paradox. Actively involving the public in the decision-making process tends to contribute to the growth and survival of various interest groups. Not involving the public means damage to credibility and conflict with values concerning participatory democracy. Resolution in this area can only be achieved when a comprehensive, coordinated national approach to hazardous waste management emerges. 26 refs.

A low temperature (24 K) distillation system for separating mixtures of hydrogen isotopes has been designed, fabricated, and delivered for use as the main component of the Hydrogen Isotope Separation System (HISS) at Mound. The HISS will handle feed mixtures of all six isotopic species of hydrogen (H2, HD, HT, D2, DT, T2) and will enrich the tritium while producing a stackable raffinate. Arther D. Little, Inc. (ADL) was the prime contractor for the distillation system. The design and fabrication techniques used for the HISS distillation system are similar to those used for previous stills which were also designed and built by ADL. The distillation system was tested with mixtures of protium and deuterium at the ADL shop. This system, as well as the feed, product, and raffinate handling systems are presently being installed at Mound where integrated testing is scheduled next calendar year.