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Global warming and nuclear power

Description: Nuclear fission power reactors represent a potential solution to many aspects of global change possibly induced by inputting of either particulate or carbon or sulfur oxides into the Earth`s atmosphere. Of proven technological feasibility, they presently produce high-grade heat for large-scale electricity generation, space heating and industrial process-energizing around the world, without emitting greenhouse gases or atmospheric particulates; importantly, electricity production costs from the best nuclear plants presently are closely comparable with those of the best fossil-fired plants. However, a substantial number of issues currently stand between nuclear power and widespread substitution for large stationary fossil fuel-fired systems. These include perceptual ones regarding both long-term and acute operational safety, plant decommissioning, fuel reprocessing, radwaste disposal, fissile materials diversion to military purposes and - perhaps most seriously- readily quantifiable concerns regarding long-term fuel supply and total unit electrical energy cost. We sketch a road-map for proceeding from the present situation toward a nuclear power-intensive world, addressing along the way each of the concerns which presently impede widespread nuclear substitution for fossil fuels, particularly for coal in the most populous and rapidly developing portions of the world, e.g., China and India. This `design to societal specifications` approach to large-scale nuclear fission power systems may lead to energy sources meeting essentially all stationary demands for high-temperature heat. Such advanced options offer a human population of ten billion the electricity supply levels currently enjoyed by Americans for 10,000 years. Nuclear power systems tailored to local needs-and-interests and having a common advanced technology base could reduce present-day world-wide C0{sub 2} emissions by two-fold, if universally employed. By application to small mobile demands, a second two-fold reduction might be attained. Even the first such halving of carbon intensivity of stationary-source energy production world-wide might permit continued slow power-demand growth in the highly developed countries and rapid ...
Date: July 10, 1998
Creator: Wood, L., LLNL
Partner: UNT Libraries Government Documents Department

Global warming and ice ages: I. prospects for physics based modulation of global change

Description: It has been suggested that large-scale climate changes, mostly due to atmospheric injection of greenhouse gases connected with fossil-fired energy production, should be forestalled by internationally-agreed reductions in, e.g., electricity generation. The potential economic impacts of such limitations are obviously large: greater than or equal to $10{sup 11}/year. We propose that for far smaller - less than 1% - the mean thermal effects of greenhouse gases may be obviated in any of several distinct ways, some of them novel. These suggestions are all based on scatterers that prevent a small fraction of solar radiation from reaching all or part of the Earth. We propose research directed to quite near-term realization of one or more of these inexpensive approaches to cancel the effects of the greenhouse gas injection. While the magnitude of the climatic impact of greenhouse gases is currently uncertain, the prospect of severe failure of the climate, for instance at the onset of the next Ice Age, is undeniable. The proposals in this paper may lead to quite practical methods to reduce or eliminate all climate failures.
Date: August 15, 1996
Creator: Teller, E.; Wood, L. & Hyde, R.
Partner: UNT Libraries Government Documents Department

Completely automated nuclear reactors for long-term operation

Description: The authors discuss new types of nuclear fission reactors optimized for the generation of high-temperature heat for exceedingly safe, economic, and long-duration electricity production in large, long-lived central power stations. These reactors are quite different in design, implementation and operation from conventional light-water-cooled and -moderated reactors (LWRs) currently in widespread use, which were scaled-up from submarine nuclear propulsion reactors. They feature an inexpensive initial fuel loading which lasts the entire 30-year design life of the power-plant. The reactor contains a core comprised of a nuclear ignitor and a nuclear burn-wave propagating region comprised of natural thorium or uranium, a pressure shell for coolant transport purposes, and automatic emergency heat-dumping means to obviate concerns regarding loss-of-coolant accidents during the plant`s operational and post-operational life. These reactors are proposed to be situated in suitable environments at {approximately}100 meter depths underground, and their operation is completely automatic, with no moving parts and no human access during or after its operational lifetime, in order to avoid both error and misuse. The power plant`s heat engine and electrical generator subsystems are located above-ground.
Date: January 1, 1996
Creator: Teller, E.; Ishikawa, M. & Wood, L.
Partner: UNT Libraries Government Documents Department

Cosmic Bombardment IV: Averting catastrophe in the here-and-now

Description: At the present time, it is at least arguable that large-scale cosmic bombardment has been a major driver of the evolution of the terrestrialbiosphere. The fundamental motivation of the present paper is the (high) likelihood that the advent and rise of the human species hasn`t coincided with the cessation of soft and hard collisions in the Asteroid Belt or in the Oort Cloud, and that we will either stop the cosmic bombardment or it will eventually stop us. In the foregoing, briefly reviewed the prospects for active planetary defenses against cosmic bombardment in the very near-term, employing only technologies which exist now and could be brought-to-bear in a defensive system on a one-decade time-scale. We sketch various means and mechanisms from a physicist`s viewpoint by which such defensive systems might detect threat objects, launch interdiction machinery toward them and operate such machinery in their vicinity to alternately deflect, disperse or vaporize objects in the 0.1-10 km-diameter range, the ones whose size and population constitute the greatest threats to our biosphere. We conclude that active defenses of all types are readily feasible against 0.1 kmdiameter incoming cosmic bomblets and that even complete vaporization-class defenses are feasible against 1 km-diameter class objects of all compositions. When facing Great Extinctors of up to 10 km diameter, the feasible defensive methods depend upon the object`s size and composition. Dispersion defenses are feasible against all threat-classes, as are deflection approaches for bomblets up to {approximately} 10 km diameter; vaporization-level protection is, however, available only against dirty snowballs` of the {approximately} 1--2 km diameter class. Great Extinctors of sizes significantly greater than 10 km diameter challenge contemporary human technology ever more severely; fortunately, they appear to be rare on the several Aeon time-scales over which Sol will shift its spectral class.
Date: September 23, 1994
Creator: Wood, L.; Hyde, R.; Ishikawa, M. & Ledebuhr, A.
Partner: UNT Libraries Government Documents Department

Cosmic bombardment V: Threat object-dispersing approaches to active planetary defense

Description: Earth-impacting comets and asteroids with diameters {approx}0.03 - 10 km pose the greatest threats to the terrestrial biosphere in terms of impact frequency-weighted impact consequences, and thus are of most concern to designers of active planetary defenses. Specific gravitational binding energies of such objects range from 10{sup -7} to 10{sup -2} J/gm, and are small compared with the specific energies of 1x10{sup 3} to 3x10{sup 3} J/gm required to vaporize objects of typical composition or the specific energies required to pulverize them, which are 10{sup -1} to 10 J/gm. All of these are small compared to the specific kinetic energy of these objects in the Earth- centered frame, which is 2x10{sup 5} to 2x10{sup 6} J/gm. The prospect naturally arises of negating all such threats by deflecting, pulverizing or vaporizing the objects. Pulverization-with-dispersal is an attractive option of reasonable defensive robustness. Examples of such equipments - which employ no explosives of any type - are given. Vaporization is the maximally robust defensive option, and may be invoked to negate threat objects not observed until little time is left until Earth-strike, and pulverization-with-dispersal has proven inadequate. Physically larger threats may be vaporized with nuclear explosives. No contemporary technical means of any kind appear capable of directly dispersing the -100 km diameter scale Charon- class cometary objects recently observed in the outer solar system, although such objects may be deflected to defensively useful extents. Means of implementing defenses of each of these types are proposed for specificity, and areas for optimization noted. Biospheric impacts of threat object debris are briefly considered, for bounding purposes. Experiments are suggested on cometary and asteroidal objects.
Date: May 24, 1995
Creator: Teller, E.; Wood, L.; Ishikawa, M. & Hyde, R.
Partner: UNT Libraries Government Documents Department

WET MARS: plentiful, readily-available martian water and its implications

Description: Water and its major constituent, oxygen, in large specific quantities are essential for maintenance of human life. Providing them in adequate quantities is widely believed to be a major challenge for human Mars exploration and settlement. The Martian regolith isn't known to bear either water or hydrogen, the ice-rich Martian polar regions are thermally inhospitable, and the measured water content of Mars' thin atmosphere represents a layer of liquid water of average thickness only about 1% that of the Moon: {approximately}0.001 cm. Crucially, however, the atmospheric Martian water inventory is advected to everyplace on Mars by meteorological phenomena, so that the few cubic kilometers of liquid water-equivalent in the atmosphere are available most anywhere when, merely for the effort of condensing it. Well-engineered apparatus deployed essentially anywhere on Mars can condense water from the atmosphere in daily quantities not much smaller than its own mass, rejecting into space from radiators deployed over the local terrain the water's heat-of-condensation and the heat from non-ideality of the equipment's operation. Thus, an optimized, photovoltaically-powered 0.3 ton water-condensing system could strip 40 tons of water each year from {approximately}10{sup 4} times this mass of thin, dry Martian air. Given a 480 set I{sub sp} of H{sub 2}-O{sub 2} propulsion systems exhausting into the 6 millibar Mars-surface atmosphere and the 5.0 km/s Martian gravity well, {ge}40 tons of water two-thirds converted into 5:1 O{sub 2}/H{sub 2} cryogenic fuel could support exploration and loft a crew-of-four and their 8-ton ascent vehicle into Earth-return trajectory. The remaining water and excess oxygen would suffice for half-open-cycle life support for a year's stay on Mars. A Mars Expedition thus needs to land only explorers, dehydrated food, habitation gear and unfueled exploration I Earth-return equipment - and a water/oxygen/fuel plant with embedded power supply which operates on Martian atmospheric water. ...
Date: August 12, 1999
Creator: Hyde, R; Ishikawa, M; Nuckolls, J; Whitehead, J & Wood, L
Partner: UNT Libraries Government Documents Department

Problem free nuclear power and global change

Description: Nuclear fission power reactors represent a solution-in-principle to all aspects of global change possibly induced by inputting of either particulate or carbon or sulfur oxides into the Earth`s atmosphere. Of proven technological feasibility, they presently produce high- grade heat for electricity generation, space heating and industrial process-driving around the world, without emitting greenhouse gases or atmospheric particulates. However, a substantial number of major issues currently stand between nuclear power implemented with light- water reactors and widespread substitution for large stationary fossil fuel-fired systems, including long-term fuel supply, adverse public perceptions regarding both long-term and acute operational safety, plant decommissioning, fuel reprocessing, radwaste disposal, fissile materials diversion to military purposes and - perhaps more seriously - cost. We describe a GW-scale, high-temperature nuclear reactor heat source that can operate with no human intervention for a few decades and that may be widely acceptable, since its safety features are simple, inexpensive and easily understood. We provide first-level details of a reactor system designed to satisfy these requirements. Such a back-solving approach to realizing large-scale nuclear fission power systems potentially leads to an energy source capable of meeting all large-scale stationary demands for high- temperature heat. If widely employed to support such demands, it could, for example, directly reduce present-day world-wide CO{sub 2} emissions by two-fold; by using it to produce non-carbonaceous fuels for small mobile demands, a second two-fold reduction could be attained. Even the first such reduction would permit continued slow power-demand growth in the First World and rapid development of the Third World, both without any governmental suppression of fossil fuel usage.
Date: August 15, 1997
Creator: Teller, E.; Wood, L.; Nuckolls, J.; Ishikawa, M. & Hyde, R.
Partner: UNT Libraries Government Documents Department

WET MARS: Plentiful, Readily-Available Martian Water and its Implications

Description: Water and its major constituent, oxygen, in large specific quantities are essential for maintenance of human life. Providing them in adequate quantities is widely believed to be a major challenge for human exploration and settlement of Mars. The Martian regolith isn't known to bear either water or hydrogen, the ice-rich Martian polar regions are thermally inhospitable, and the measured water content of Mars' thin atmosphere represents a layer of liquid water of average thickness only {approx}1% that available on the Moon, or {approx}0.001 cm. Crucially, however, the atmospheric Martian water inventory is advected meteorologically to everyplace on Mars, so that the few cubic kilometers of liquid water-equivalent in the atmosphere are available anywhere when, merely for the effort of condensing it. Well-engineered apparatus deployed essentially anywhere on Mars can condense water from the atmosphere in daily quantities not much smaller than its own mass, rejecting into space from radiators deployed over the local terrain the water's heat-of-condensation and the heat from non-ideality of the equipment's operation. Thus, an optimized, photovoltaically-powered water-condensing system of {approx}0.3 tons mass could strip 40 tons of water each year from {approx} 10{sup 4} times this mass of thin, dry Martian air. Given a 490 set I{sup sp} of H{sub 2}-O{sub 2} propulsion systems exhausting into the 6 millibar Mars-surface atmosphere and the 5.0 km/s Martian gravity well, {approx}40 tons of water two-thirds converted into 5:1 O{sub 2}/H{sub 2} cryogenic fuel could support exploration and loft a crew-of-four and their 8-ton ascent vehicle into Earth-return trajectory. The remaining H{sub 2}O and excess O{sub 2} would suffice for half-open-cycle life support for a year's exploration-intensive stay on Mars. A Mars Expedition thus needs to land only explorers, dehydrated food, habitation gear and unfueled exploration/Earth-return equipment--and a water/oxygen/fuel plant exploiting Martian atmospheric water. All of the oxygen, water ...
Date: September 14, 1999
Creator: Hyde, R.; Ishikawa, M.; Nuckolls, J.; Whitehead, J. & Wood, L.
Partner: UNT Libraries Government Documents Department

Premonitory Martensitic Surface Relief Via Novel X-Ray Diffuse and Laser Light Reflectivity from the (001)-Surface of a NI(sub 63)AL(sub 37) Single Crystal

Description: Both x-ray diffuse reflectivity and laser light scattering have been used to investigate the temperature-dependent surface behavior of a Ni{sub 63}Al{sub 37} single crystal on different length scales. In-situ experiments were performed above the conventional martensitic start temperature M{sub s}. to search for premartensitic phenomena. X-ray experiments showed the presence of a surface precursor with second-order (continuous) character several 10 K above M{sub s}. This premonitory effect corresponds to a height-height-correlation function which changes on the nanometer scale as the martensitic transformation is approached. At the martensitic transformation, the surface morphology changed from nanoscopic roughness to macroscopic relief within a temperature interval of less than 1 K via intermediate stages. Laser light scattering was employed to study time-dependent aspects of the athermal martensitic transformation above M{sub s}. The occurrence of a martensitic transformation on isothermal holding after a certain incubation period was observed in Ni-Al for the first time. The measured incubation times increased by four orders of magnitude within a temperature interval of 0.5 K.
Date: November 29, 1999
Creator: Klemradt, U.; Aspelmeyer, M.; Abe, H.; Wood, L. T.; Moss, S. C.; Dimasi, E. et al.
Partner: UNT Libraries Government Documents Department

Long-range weather prediction and prevention of climate catastrophes: a status report

Description: As the human population of Earth continues to expand and to demand an ever-higher quality-of-life, requirements for ever-greater knowledge--and then control--of the future of the state of the terrestrial biosphere grow apace. Convenience of living--and, indeed, reliability of life itself--become ever more highly ''tuned'' to the future physical condition of the biosphere being knowable and not markedly different than the present one, Two years ago, we reported at a quantitative albeit conceptual level on technical ways-and-means of forestalling large-scale changes in the present climate, employing practical means of modulating insolation and/or the Earth's mean albedo. Last year, we reported on early work aimed at developing means for creating detailed, high-fidelity, all-Earth weather forecasts of two weeks duration, exploiting recent and anticipated advances in extremely high-performance digital computing and in atmosphere-observing Earth satellites bearing high-technology instrumentation. This year, we report on recent progress in both of these areas of endeavor. Preventing the commencement of large-scale changes in the current climate presently appears to be a considerably more interesting prospect than initially realized, as modest insolation reductions are model-predicted to offset the anticipated impacts of ''global warming'' surprisingly precisely, in both space and time. Also, continued study has not revealed any fundamental difficulties in any of the means proposed for insolation modulation and, indeed, applicability of some of these techniques to other planets in the inner Solar system seems promising. Implementation of the high-fidelity, long-range weather-forecasting capability presently appears substantially easier with respect to required populations of Earth satellites and atmospheric transponders and data-processing systems, and more complicated with respect to transponder lifetimes in the actual atmosphere; overall, the enterprise seems more technically feasible than originally anticipated.
Date: August 18, 1999
Creator: Caldeira, K; Caravan, G; Govindasamy, B; Grossman, A; Hyde, R; Ishikawa, M et al.
Partner: UNT Libraries Government Documents Department

The STAR Time Project Chamber

Description: Paper presented at the International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions (1999) reporting on the progress of the STAR experiment, a complex system of many detector sub-systems which have been installed in a large solenoidal magnet at the Relativistic Heavy Ion Collider (RHIC).
Date: May 10, 1999
Creator: Argonne National Laboratory
Partner: UNT Libraries Government Documents Department

Recent developments on the STAR detector system at RHIC

Description: The STAR detector system is designed to provide tracking, momentum analysis and particle identification for many of the mid-rapidity charged particles produced in collisions at the RHIC collider. A silicon vertex detector (SVT) provides three layers of tracking near the interaction point. This is followed by the main time projection chamber (TPC), which continues tracking out to 200 cm radial distance from the interaction region. The detector design also includes an electromagnetic calorimeter, various trigger detectors, and radial TPCs in the forward region. The entire system is enclosed in a 0.5 T solenoid magnet. A progress report is given for the various components of the STAR detector system. The authors report on the recent developments in the detector proto-typing and construction, with an emphasis on the main TPC, recent TPC cosmic ray testing and shipping to Brookhaven National Laboratory.
Date: December 1997
Creator: Argonne National Laboratory
Partner: UNT Libraries Government Documents Department