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The report discusses the current status of liquid-metal fast breeder reactor (LMFBR) development and one of the principal safety issues, a hypothetical core-disruptive accident (HCDA). Bibliographic information on worldwide LMFBRs relative to the development of the breeder reactor as a safe source of nuclear power is presented for the period 1972 through 1974. The bibliography consists of approximately 1380 abstracts covering research and development and operating experiences leading up to the present design practices that are necessary for the licensing of breeder reactors. Key-word, author, and permuted-title indexes are included.

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The exposures of noncellulosic ultrafiltration membranes to a radioactive environment simulating up to 24 months of exposure to a ..beta.. dose of 10 ..mu..Ci/cm/sup 3/, a ..gamma.. dose of 10/sup -5/ ..mu..Ci/cm/sup 3/, and an ..cap alpha.. dose of 4.9 x 10/sup -3/ ..mu..Ci/cm/sup 3/ were completed. Exposure to ..beta.. and ..gamma.. radiation did not affect membrane performance. After a simulated six months of exposure to ..cap alpha.. radiation some degradation of membrane performance occurred. Several experiments were made on a laboratory-scale reverse-osmosis unit using the product from ultrafiltration as feed. Rejection of activity ranged from 88 to 99 percent. The ''continuous'' ultrafiltration pilot run was completed. Approximately 40,000 gal were processed in over 70 hr of operating time without shutdown for cleaning. Flux and rejection were maintained relatively steady over this period. Rejection of gross alpha ranged from 80 to 99.5 percent depending on the ionic content of the waste stream. Flux rates ranged from 5 to 8 liters/min over this period. The engineering column tests were continued using uranium-233 with product from the ultrafiltration pilot plant. Flow rates and pH were varied in order to determine optimum operating conditions.

PBF acoustic filter Unit No. 1 cracked when heat treatment was attempted. The effects of prior thermal cycling, solution anneal temperature, and cooling rate from solution anneals were investigated. The investigations concerned influences of the above variables upon both 1400$sup 0$F stress rupture solution- annealed properties and room temperature age-hardened properties. 1400$sup 0$F stress rupture properties were of interest to assist the prevention of cracking during heat treatments. Room temperature age-hardened properties were needed to ensure that design requirement would be provided. Prior thermal cycling was investigated to determine if extra thermal cycles would be detrimental to the repaired filter. Slow furnace cools were considered as a means of reducing thermal stresses. Effects of solution annealing at 2000 and 1900$sup 0$F were also determined. Test results showed that slow cooling rates would not only reduce thermal stresses but also improve 1400$sup 0$F ductility. A modified aging treatment was established which provided the required 145 ksi room temperature yield strength for the slowly cooled material. Prior cooling did not degrade final age-hardened room temperature tensile or impact properties. (auth)

Thermodynamic studies are of interest for any chemically reacting system. Thermodynamics constitute the limiting cases for kinetically reacting systems. In many systems, as a result of the exponential nature of most chemical reactions (reaction rate = k Ae/sub -..delta..H/RT/), reactions of interest occur over a fairly narrow temperature region. At lower temperatures, reaction rates are negligible, while at higher temperatures the reaction can be so rapid as to be controlled either by thermodynamics or mass transfer. Thus, thermodynamic equilibrium at a characteristic temperature can often be a close approximation to a kinetic system. Previous work by Stephens in the coal-water-oxygen thermodynamic system is extended. Results with 20 percent combustion and amorphous carbon are shown to be a good approximation to kinetic data. Experimental Lurgi coal gasification data are closely approximated by a calculated thermodynamic temperature of 1060 K. This temperature is used to show that for underground coal gasification with a constant oxygen/coal ratio, optimum steam/oxygen ratios should be as low as possible. Probably the steam/oxygen ratio should exceed 3.6 to avoid slagging of the ash. At this ratio, about twice as much methane can be obtained in comparison to the Lurgi ratio of 7.7. (auth)

A preliminary set of experiments was conducted in order to determine the sorptive characteristics of rock with respect to ionic species under conditions of dynamic flow of an aqueous solution through a rock core. The results of the dynamic experiments have been compared to the results of static or batch experiments which were conducted under corresponding physical and chemical conditions. It was found that, gram for gram, sorption of the ion of interest was always greater in the dynamic experiments. These results are contrary to early predictions and indicate that the effect of rock surface area on adsorption was overshadowed by another parameter. It has been suggested as a working hypothesis that the competitive effect of ions that were dissolved and/or leached from the rock in batch experiments has resulted in reduced sorption of the ion of interest. If the hypothesis is confirmed by further experimental work, a ramification of the study is that calculations concerning transport of radioactivity in groundwater which utilize input parameters derived from static tests will tend to be conservative with respect to what occurs in nature. (auth)

The OF-2 irradiation experiment was designed and built to test candidate High-Temperature Gas-Cooled Reactor (HTGR) fuel and fuel-rod matrix designs. The capsule was designed with two separate specimen cells, allowing for independent temperature control as well as independent fission gas release measurements. The OF-2 capsule is presently operating at the Oak Ridge Research Reactor (ORR). Initial fuel rod linear heat rates are between 16.4 and 23.0 kW/m (5 and 7 kW/ft) and fuel centerline temperatures are approximately 1150 and 1350/sup 0/C. Plans are to operate the capsule for nine ORR cycles to accumulate a maximum damage fluence of 9 x 10/sup 21/ neutrons/cm/sup 2/ (E > 0.18 MeV).

It is pointed out that corrections due to the Coulomb-nuclear interference could amount to an order of 1 to 2 mb at P/sub lab/ around 1 GeV/c in recently performed measurements of the pp-total cross section difference in pure spin states.