摘要:

AbstractTo honor Alvin Weinberg for his role as one of the key architects of the nuclear age, it seems appropriate to include a brief account of his involvement in nonnuclear activities. The time span covered includes two critical periods for energy policy–1973, immediately prior to the oil embargo, and 1974 to 1975, the most traumatic years of the period immediately following the embargo. The first period is illustrated by Weinberg’s involvement with the Club of Rome and the second period by his service as head of the Energy Research and Development Office of the Federal Energy Administration. His far-sighted views on energy and natural resource policy at that time are contrasted with the perceptions of others who were seeking radical technological and institutional solutions for crises that, in the end, were solved by the interplay of market forces and evolutionary progress in energy supply and conservation, and the use of natural resources.

ISSN:0029-5639    

DOI:10.13182/NSE85-A18479

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor

摘要:

AbstractAn account is given of some nuclear measurements that apparently had some importance in the early days of the nuclear chain reaction. These include measurements of the decay periods and the intensity of the delayed neutrons (important for the control of the chain reaction), and the first measurements relative to a fast-neutron chain reaction in uranium metal. The latter showed that normal uranium would have to be enriched by a factor of more than 12 in order to sustain a fast-neutron chain reaction in a finite geometry, and that high enrichment would be needed for a nuclear weapon. They also suggested to reactor theorists that the interaction fast effect might make an important contribution to a controlled slow-neutron chain reaction using natural water as moderator/coolant. (In the capable hands of others, this perception of the theorists led eventually to most of the civilian and naval power reactors.) Items of personal research are briefly mentioned, viz., observation of the radioactive decay of the free neutron, of nuclear recoil due to neutrino emission, and of the atomic consequences of radioactive decay. The periods covered are 1940–1944 with the Cyclotron Group at the Metallurgical Laboratory, Chicago, and 1944–1968 at Oak Ridge, Tennessee.

ISSN:0029-5639    

DOI:10.13182/NSE85-A18480

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor

摘要:

AbstractAlvin Weinberg has contributed substantially to the debate over strategic nuclear weapons policy on averting nuclear war. His views over the past 25 years have been remarkably consistent, involving a strong preference for combining defensive systems with offensive disarmament. These principles have placed him at odds with the core of conventional strategic thought in this country, which has argued against the construction of defenses. President Reagan’s“Star Wars”proposal, however, has led to a rethinking of fundamental first principles, and reintroduced the possibility of defenses. Weinberg’s latest contribution to this debate, something he calls“Defense-Protected Build-down,”has the potential to be quite influential in guiding future strategic thought.

ISSN:0029-5639    

DOI:10.13182/NSE85-A18481

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor

ISSN:0029-5639    

DOI:10.13182/NSE85-A18482

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor

ISSN:0029-5639    

DOI:10.13182/NSE85-A18483

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor

摘要:

AbstractA personal history of the development of molten salt reactors in the United States is presented. The initial goal was an aircraft propulsion reactor, and a molten fluoride-fueled Aircraft Reactor Experiment was operated at Oak Ridge National Laboratory in 1954. In 1956, the objective shifted to civilian nuclear power, and reactor concepts were developed using a circulating UF4-ThF4fuel, graphite moderator, and Hastelloy N pressure boundary. The program culminated in the successful operation of the Molten Salt Reactor Experiment in 1965 to 1969. By then the Atomic Energy Commission’s goals had shifted to breeder development; the molten salt program supported on-site reprocessing development and study of various reactor arrangements that had potential to breed. Some commercial and foreign interest contributed to the program which, however, was terminated by the government in 1976. The current status of the technology and prospects for revived interest are summarized.

ISSN:0029-5639    

DOI:10.13182/NSE90-374

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor

摘要:

AbstractIn the seed-blanket core concept, the major portion of the core power is typically produced in subcritical regions known as“blankets.”The small supercritical regions that drive the blankets are known as“seeds.”The concept lends itself to geometry control in which moving the seeds varies the leakage of neutrons into fertile material, thus avoiding the loss of neutrons to parasitic control devices. As a burner, the seed-blanket concept has significant advantages in the reduction of initial fuel loading and improvement in resource utilization.As a breeder, the seed-blanket concept has further advantages in making it feasible to obtain negative void and moderator reactivity coefficients. A summary is presented of recent studies of the application of the seed-blanket core concept with both heavy water and light water moderation.

ISSN:0029-5639    

DOI:10.13182/NSE85-A18485

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor

摘要:

AbstractFor some time small high-temperature reactors, because of their special safety properties, have been of interest to various countries. The prototype of these facilities is the Arbeitsgemeinschaft Versuchsreaktor in Jülich. During the past 17 years of operation, the components of the reactor, especially the fuel elements, have proved suitable for achieving permanent temperatures of the heat transfer medium of up to 950°C with low contamination of the loop. The convincing safety behavior of the reactor has been demonstrated. It is apparent that for this design an afterheat removal system is not required, since the afterheat can be adequately removed by heat conduction. In addition to the thorium/uranium fuel cycle originally planned, utilization of low-enrichment uranium in the fuel elements has also been fully developed.

ISSN:0029-5639    

DOI:10.13182/NSE85-A18486

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor

摘要:

AbstractA new ultrasafe type of nuclear power plant is described that has a complete“walk-away-from”characteristic. That is, the reactor can safely dissipate its shutdown heat even if its power and water supplies are cut off. The reactor is steam cooled and is designed to operate at one fixed steam density. Its reactivity characteristics are such that if the power level increases, the steam becomes less dense than the optimum and tends to shut the reactor off. Similarly, if the reactor is flooded with water, the reactivity greatly decreases and also shuts the reactor down. The reactor can be operated as a burner, a high-efficiency converter, or a breeder, depending on the isotopic content of the fuel. The plant operates at low pressure and relatively high efficiency with an example given at 1000 psia and 35% efficiency. The reactor is enclosed in a conventional steel vessel resembling a boiling water reactor. The vessel is connected to a large atmospheric pressure pool of water, and shutdown consists of passively coupling the pool to the reactor through the loss of steam flow. Shutdown cooling is provided by forced air and natural draft convection cooling of the pressure vessel. Sufficient water and passive cooling are provided by the pool for many months of shutdown water cooling. The plant piping is double walled, and all paths of radiation escape, including pressure-vessel cracking, are channeled through an on-line cleanup system.

ISSN:0029-5639    

DOI:10.13182/NSE85-A18487

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor

摘要:

AbstractCurrent light water reactors (LWRs) depend for the protection of core integrity on a multitude of active systems and components, such as instrumentation, cables, electronic logics, relays, actuators, etc., and on human judgment. This approach to safety has led to a complex and expensive plant design in which all parts of the plant where these systems are present must be protected against damage due to, e.g., earthquake. It has also failed to persuade the public about the safety of the reactors because of the existing (but very small) probability of multiple failures leading to core meltdown.With the process inherent ultimate safety (PIUS) approach, this dependence on active systems is eliminated. The safety is now no longer a result of their intervention but is built into the thermohydraulics of the primary system itself. The PIUS primary system response to a number of severe anticipated transients without scram (ATWS) is described, as studied by means of a specially developed computer simulation program.The method is shown by which the thermohydraulic self-protection properties of the primary system terminates these ATWS transients, which could have severe consequences in a conventional LWR, with neither the core nor the rest of the plant suffering any damage (beyond the initial failure assumed).This has important economic consequences. The surveillance and control systems used to run the plant and the buildings in which they are housed can be designed as for a fossil plant, since they no longer have the ultimate responsibility for nuclear safety. The ensuing design simplification pays for the more expensive pressure vessel and primary system. Inherent safety is obtained as a bonus.

ISSN:0029-5639    

DOI:10.13182/NSE85-A18488

出版商:Taylor&Francis    

年代:1985

数据来源: Taylor