Literature Review
James O'Toole and the University of Southern California Center for Futures Research presents several models in Energy and Social Change; part of one is introduced here.  Two of five lessons from history on energy and social change are (O'Toole 1978:xiv-xv):
1.  Energy is scarce or abundant only relative to available technologies.
2.  A minor technological breakthrough can have profound social and political implications.
It is held by some that the fast breeder reactor, at 50% efficiency is capable of extracting 100 times the energy from Uranium fuel (which is mostly non-fissile U-238) that a LWR can claim (Hoyle 1980:68).  Another example, one to illustrate breakthroughs having profound implications (Wiesner and York 1964:3):
From the blockbuster of World War II to the thermonuclear bomb the violence of military explosives has been scaled upward a million times.  The time required for the interhemispheric transport of weapons of mass destruction has shrunk from 20 hours for the 300-mile-per-hour B-29 to the 30-minute flight time of the ballistic missile.

The Non-Proliferation Treaty of 1968 was designed to prevent the spread of nuclear weapons beyond the then five nuclear countries: United States, Soviet Union, United Kingdom, France and China.  The ineffectiveness of the treaty was well known by May, 1974 when India successfully exploded an underground peaceful" nuclear device.  William Epstein (1980:196), in The Proliferation of Nuclear Weapons," criticizes the U.S. and the U.S.S.R., both of whom signed and ratified the treaty, for having failed to discontinue all nuclear-weapons tests and halt the arms race as required by some of the treaty provisions.  The treaty was intended to make available the benefits of the peaceful applications of nuclear technology (including nonmilitary nuclear explosives) to all parties of the treaty" while preventing non-nuclear weapon nations from possessing nuclear bombs.  Epstein proposes that an international regime be established (outside of the treaty framework and preferably by the United Nations) to perform peaceful nuclear explosions (perhaps free of charge) for the non-nuclear-weapons states (Epstein 1980:207-209), presumably to eliminate the peaceful incentives to develop nuclear devices.  This will not discourage non-nuclear weapons states from building bombs, because according to Siever (1980:194), (a)s Epstein sees it, the lack of trust in the big powers by the smaller ones and the insecurity of many of those countries who feel threatened by their neighbors will always operate to push them into producing nuclear bombs."
In The Decision to Use the Atomic Bomb," Henry L. Stimson (1976:172), former U.S. Secretary of War (1940-1945), reflects on the numbers of lives to be lost, both Japanese and American, in conventional warfare and the alternative, halting the war quickly with the atomic bomb:
My chief purpose was to end the war in victory with the least possible cost in lives of the men in the armies which I had helped to raise.  In the light of the alternatives which, on a fair estimate, were open to us I believe that no man, in our position and subject to our responsibilities, holding in his hands a weapon of such possibilities for accomplishing this purpose and saving those lives, could have failed to use it and afterward looked his countrymen in the face.

Presented with a similar scenario, it is not unlikely that a patriot in any country, faced with formidable opponents (consider the heated Iraq-Iran conflicts of the early 1980's) and armed with nuclear devices, would conclude to issue a devastating blow (unless perhaps, there exists a real risk that the opposition will respond with a severe retaliation).  Thus a major concern among nuclear proponents and opponents alike, according to Hoyle (1980:71), is that less-advanced nations might find a way to obtain nuclear weapons through civil energy producing reactors and facilities supplied to them by technically more advanced nations."  But the civil energy route is only one route among several alternatives for countries seeking nuclear materials.
David J. Rose and Richard K. Lester (1980:213-225) have mapped out--in flow chart style--several possible scenarios by which non-nuclear weapons states may obtain nuclear weapons.  The findings of their study maintain that (A) decreased U.S. involvement in (1) nuclear fuels reprocessing and (2) fast breeder development (halted by Jimmy Carter while he was U.S. President), and hence decreased international efforts in developing breeders, reprocessing plants and safeguards, and (B) allied dissatisfaction, will undermine American efforts to control the proliferation of nuclear weapons.
Already existing tensions among countries are exacerbated by rapidly declining oil reserves.  Nuclear power, already proven economic and reliable, if also developed to be safe, could conceivably supply a large portion of the energy requirements of many countries.  This would be especially important to the many countries possessing few energy supplies because, according to Chayes (1976:30), the likely seed-bed for international violence in the years ahead will be claims to a 'fair share' of the world's goods . . .".  Chayes (1976:30-32) foresees problems in the efforts to control the military (and paramilitary) implications of the inevitable spread of nuclear knowledge and technology", and criticizes the hard-sell" approach by international nuclear power firms who disregard the impact of their operations on non-proliferation objectives:  The time has come for a much stricter regulatory policy enforced by the suppliers to supplement IAEA (International Atomic Energy Agency) safeguards."
Nuclear Reactor Schemes
Very briefly, there are many technical schemes for taking heat from a reactive core for generating electricity.  In the LWR, normal (light) water that has been de-salted" is maintained under pressure so that it doesn't boil.  Heat is transferred by a heat exchanger to another water reservoir, not under pressure, where steam is produced which spins a turbine connected to an electricity generator.  Reactor fuel for the LWR is enriched Uranium; said enrichment (only 3% in U.S. reactors) is necessary because light water is a poor moderator.  The heavy water reactor (e.g., Canadian Deuterium, CANDU), because heavy water is a good moderator, needs no enriched uranium fuel (heavy water is expensive, light water is not).
Agnew (1981:56) observed that HTGR's are very efficient, 38.5 percent, compared to the LWR's with thermal efficiencies of 32 to 33 percent.  Different from the LWR, there is little risk of a loss-of-coolant accident for two reasons noted by Agnew (1981:55-57):
First, since the reactor core is cooled by a circulating gas completely confined within a massive reactor vessel, the reactor cannot lose its coolant because of a rupture of pipes outside the vessel.   Second, if the circulation of the gas is interrupted by some mishap to all of the main helium-circulation system, the temperature within the reactor core rises only slowly because the fuel elements are embedded in a massive matrix of graphite.  (that serves a moderator and a heat sink).

Gas cooled reactors require large containment structures, and early versions required highly enriched fuel because helium is a poor moderator.  Modern gas-cooled reactors, such as the HTGR, according to Agnew (1981:56), . . . contain nearly 1,500 tons of graphite, which has a high capacity for absorbing heat. . ." and therefore is not as vulnerable as a LWR is to . . . an interruption in the flow of coolant or loss of coolant"; such an interruption caused the Three Mile Island accident.  Fast breeder reactors produce more fuel than consumed.  A blanket of U-238 is gradually converted to Pu-239 (with U-239 and Np-239 as intermediaries) while capturing fast neutrons.  Once the Pu-U blanket is reprocessed, extracted Pu-239 becomes available for use as fuel in other reactors.  Since non-fissile U-238 comprises 99.28 percent of natural uranium, the conversion of it to Plutonium significantly extends the energy resource base.  The LMFBR uses liquid sodium instead of water to transfer heat from the reactor core to a steam generator.  Heat transfer is enhanced at the high temperatures needed to liquify sodium.  The drawbacks are that the sodium becomes contaminated, and if a loss of coolant accident occurs, a core meltdown is almost certain.  Also, sodium explodes when coming in contact with water.  Plutonium extracted from any reactor (it is produced whenever U-238 absorbs a fast neutron) is highly toxic.  Additionally, Plutonium-239 prepared for reactor fuel may possibly be diverted for use by terrorists or others for nuclear bombs.  Although crude nuclear devices, such as the gun-type described by Inglis (1973:178-183) is more easily (and less dangerously) constructed with uranium fuels, it may be necessary for plutonium bombs to follow the implosion type (also described by Inglis), or the fission explosive described by Frauenfelder and Henley (1974:456-459).
A further problem is the long half-life of plutonium, 24,400 years (94-Pu-239).  Thus an inherent problem of all the above described reactors is that this long lived actinide is produced and removed from the reactor core where it is susceptible to misuse, either as a toxin or as bomb fuel.  And if the Plutonium is stored away, either for possible use at a later date, or permanently, it may outlast the cannisters it is stored in, either because of corrosion or geological violence, if not first unearthed by terrorists.  The very advantage of the LMFBR--that it converts the non-fuel isotope of Uranium to fuel--is also its greatest weakness:  The reprocessing of a U-238/ Pu-239 blanket provides an opportunity for the diversion of nearly pure plutonium-239.  The risk of a loss-of-coolant accident is not particularly high for either the LWR or the LMFBR, but deployed on a large scale, accidents are likely to occur.  In both cases a temporary loss-of-coolant accident could lead to a core meltdown, or China syndrome", in which the core collapses from the over-accumulation of heat, approximately 3360 degrees F according to Davis (1978:189).  Assuming that the criteria for selection of a nuclear technology are (1) that accidents be held to a minimum and (2) that U-238 be converted to a useable fuel, thus greatly extending the resource base, one might conclude that a gas-cooled fast breeder reactor (GCFR) is the answer:
Higher . . . (efficiencies) . . . than for the LMFBR are possible . . . (h)owever, a massive
prestressed concrete vessel is needed for helium retention, and coolant provides little heat
capacity for stablizing thermal excursions.  The behavior of fuel cladding at the higher fuel
temperatures and high irradiation characteristic of the GCFR is less understood than for the
LMFBR (Reviews of Modern Physics:S18).

But if a third criteria--in situ reprocessing for the purpose of reducing risks of accidents and proliferation--is added to the above two for the selection of a nuclear power technology, then none of the above reactor schemes qualify.  We next examine the ANFR, in search of a reactor scheme that meets the above three criteria.

Actinide-Nitride Fueled Reactor
Professor Parlee and a succession of graduate students, working at the Stanford Center for Materials Research (SCMR) were funded by DOE from about 1970 to 1975, and from 1975 to 1979 by SCMR (see Parlee:Selective...Reduction..."), for investigating nitrogen-nitride reactions in the U-Sn system in hopes of identifying techniques for the preparation and purification of nuclear fuels.  Nitrogen-nitride/liquid nonferrous solvent systems were previously unresearched, or at least unreported according to Anderson and Parlee (1971:1599).  Findings reported by R.N. Anderson, et al. (1972:29) indicate that nitride precipitation offers a metallurgical separation method applicable to the reprocessing of spent fast reactor fuels: it appears possible to attain 99% uranium recovery and 98% plutonium recovery, with decontamination factors of 106."
The insitu reprocessing of nuclear wastes minimizes the risks of theft and reduces problems of environmental safety and radioactive waste storage, and is one of two main features of the ANFR.  R.N. Anderson, et al. (1972:29) discusses how ANFR research has demonstrated a fuel reprocessing technique:  (A) spent reactor fuel could be reprocessed by (1) dissolving it in tin, (2) precipitating the pure UN with nitrogen, leaving fission products (F.P.) behind in solution, (3) separating the UN and oxidizing it back to UO2 for reusable fuel, (4) concentrating the F.P. into a (F.P. + tin) metal block or ingot ready for disposal (in a high unleachable form), and (5) recycling most of the tin to the head end" of the process.  F.P. gases would be captured by conventional methods . . . (and the) . . . process would be completely dry with no water solutions, no long radioactive cooling periods" and no solution leaks or massive escapes to the environment.
According to Parlee, the advantages of the ANFR reprocessing technique over the Purex and several other processes are (see R.N. Anderson, et al. 1972:32):  (1) it is more economic, requiring less stages, less space; (2) the reprocessed fuel is in the desired form, i.e., as solid UO2 or UN; (3) it is better for high burn-up fuel", no inextractable residues;" (4) there are no huge tanks of water solutions to be burst by catastrophe (earthquake) and pollute the environment; and (5) plutonium is never at any time separated (as it is in the Purex) and is returned directly to the reactor as re-usable fuel, thus there is no danger whatsoever of Pu proliferation.  According to R.N. Anderson, et al. (1972:32), nitride precipitation may have potential application to the reprocessing of LMFBR fuel because: (1) the advantage over the Purex method is that replenished fuel can rapidly be recycled to the reactor without requiring extended storage periods for radioactive cooling; and (2) pyrochemical techniques have excellent heat transfer characteristics.  Although PuN formation data are unavailable from Anderson and Parlee (1972:298), their estimates indicate that mixtures of UN and PuN in the reactor serve as reactive precipitates.  The fission of uranium or plutonium atoms, congregated at the bottom of the core as dense UN and PuN, frees the nitrogen to precipitate more fuel while the fission products are dissolved in the tin.  If the concentration of fission products in tin expands to where these compete for nitrogen, according to Anderson and Parlee (1972:298-299), it has been found that fission product nitride formers, such as zirconium and the lanthanides, form nitrides of low density that tend to float to the surface" where removal is thus facilitated.
The whole process of nitriding uranium demands the pure metal, rather than the oxides of uranium, U3O8 and UO2.  U3O8 is concentrated and reduced to U02 fuel to be injected into the reactor area, but molecular oxygen still must be removed.  The solution thermodynamics and a proposed process design for the commercial reduction of UO2 to the pure metal were presented at the 67th Annual Meeting of the American Chemical Institute (December 1-5, 1974, Washington, D.C.).  The Carbothermic Reduction of Refractory Metals" by Anderson, R.N. and Parlee, N.A.D. (1976:526-529), is a report of the technique, which may be expressed simply as:

UO2 (s) + 2C (s) = U + 2CO (g).

Such a reduction is generally unacceptable because the product is often contaminated with carbides, but in the present case, carbide formation is avoided by lowering the reactivity of uranium metal below that required for carbide formation.  This is accomplished by the use of a solvent metal, in this case, Sn.  Thus fuel for the ANFR--as recommended by the developers in Bakshuni, et al. (1979:126)--would be UO2-C pellets.  Once pure uranium metal is available, the precipitation forming reactions (see Parlee:Selective...Reduction...":4-5):
U + 12 N2 (g) = UN(s) above 1450° C,
and 2U + 32 N2 (g) = U2N3 (s) below 1450° C,
occur in liquid tin.  (U represents uranium dissolved in liquid tin.)  Hence a second important feature of the ANFR is that the reactive process is self correcting and operates as described below by Jones (1976:55-56).
In a graphite lined core, molten tin is under light nitrogen pressure so that nitrogen is in
solution with the tin.  Uranium which is dissolved in the tin, will be precipitated as UN, the
nitride of uranium.  UN is more dense than the molten uranium-tin alloy and settles to the
bottom of the reactor vessel.
When the amount of UN reaches critical mass, fission begins and the reactor is in
operation.
However, if the temperatures rise above the planned operational levels, they will get into a
range where UN dissociates, putting uranium back into solution and reducing the size of the
UN mass.  This equilibrium provides the ANF reactor with a stability against runaway
reactions.
Conversely, as temperature drops, nitriding increases and the core condenses, enhancing the
UN mass and strengthening the fission reaction.  Again a self-correcting feature.

Such a process, according to the ANFR developers--R.N. Anderson and N.A.D. Parlee--could conceivably be applied to current reactor schemes, including the breeder varieties.  The reaction within the core is controlled by adjusting the weight of the critical mass (CM):  The weight of the CM (1) increases as the nitrogen pressure increases and decreases as the nitrogen pressure decreases, and (2) increases as the concentration of Uranium in molten metal solution increases and decreases as the concentration of tin or other solvent metal increases.  Control rods, employed primarily for added safety, are withdrawn during reactor start-up and operation stages, and inserted for reactor shut-down.  A substantial number of actinides--a series of 15 radioactive, heavy metals, those having atomic numbers 89 through 103, and the substances they form in combination with other chemical elements--are useable in the ANFR, even those formed by neutron capture and decay according to Jones (1976:55-58).

Modelling the ANFR
The ANFR is examined here with the aid of three models I have developed.  The first model is a monte-carlo simulation of the reaction tin losses which result each time fission products are removed when a combined temperature/humidity scale exceeds a given value.  This policy is presumed as an attempt to coordinate cleanup times with the demand for excess cooling capacity.  The simulation uses a reactor dynamics mode to monitor the buildup of reaction products in the core by essentially reproducing the reaction products graphs of B.L. Cohen (1977:21-31), June 1977, Scientific American.  The second model utilizes the reactor dynamics portion of the first model to monitor the levels of actinides and fission products in the reactor; the ANFR and the LWR is contrasted.  The third model provides a means for obtaining nuclear waste heat curves for several scenarios which enable comparisons of both the wastes from the ANFR and the LWR.  Mathematical descriptions of the three models are provided below (and in the Appendix, computational descriptions are given in the form of programs written in the language of the Hewlett Packard 41-CV).

<>======
First Model
Second Model
Third Model
Table 2
<>======

Results
The first model revealed that the ANFR would consume 7,575 gallons of tin in a thirty year period of operation.  The fission products removed during this period would include 8606.67 grams of CS-137 and 7131.63 grams of Sr-90.  An average of 33.7 cleanups per year would account for the tin loss which facilitates the removal of fission products (FP).  In a comparison of the ANFR and LWR. the second model revealed that the ANFR will yield only slightly more FP waste while yielding virtually no waste actinides (see Table 3).
The third model reveals that the nuclear waste heat curves are significantly lower for the ANFR as compared with the LWR. In Figure 1, curve C2 is a reasonable facsimile of the overall heating effect curve presented by B.L. Cohen (June 1977, Sci. Am.), which presumed that spent fuels were reprocessed and the majority of the useful actinides were removed.  Curve C1 suggests that the heat generation curve drops to zero watts per cannister at 999.84 years when only the FPs are stored.  Actinides are particularly long lived and the burnup of these in the ANFR results in a heat curve which drops quickly, probably within the range of C1 to C2.  For the LWR, assuming no reprocessing of spent fuels, the total heat generation curve is likely to fall within the range estimate provided, C3 to C4, the shaded zone.

<>=====
Table 3
Figure 1
<>=====

Limitations
The first two models rely on data for the LWR even though the reactions will be somewhat different in the tin environment.  Both the fission product yields and the actinide levels, when experimentally determined, will likely be in the neighborhood of the above estimates.  The third model assumes that the heat generated in the waste is due to spontaneous fissions; the estimates obtained are again likely to be in the neighborhood of the real values.  An additional limitation is associated with the differences between Cohen's curves and the line-segment-curves I used to mimic his curves; such errors are magnified by the assumptions for reactor-operating-durations.  The conclusions of the study, even in view of the foregoing limitations, will very probably remain valid.  One further limitation is that other mediums were not examined; which might prove worthwhile in a comparative study are Lithium, Sodium, Tin and Bismuth.

Observations
Modeling is a reasonable approach to investigating the dynamics of the ANFR.  These models are just a beginning since the ANFR looks promising.  The ANFR produces curium, a valuable material for a space-walker economy* and the insitu reprocessing scheme can likely be adapted to accomodate the extraction of this material.  Hence it could be structured to remove actinides which would then need to be reprocessed if plutonium or U-235 were to be removed.  I prefer a reactor design which is, in a real sense, a garbage disposal for actinides which otherwise end up as nuclear waste (which may be narrowly defined or broadly defined to include weapons materials).
The stability of the reactor may be enhanced or controlled by using variable speed pumps to control the heat-extraction rate so that the reactor doesn't slide down into the slowdown range below 1475°C (U2N3 precipate).  The temperature of disassociation for UN will be important to know for design considerations.  The shape of the containment core will affect the shape of the mass of precipitants hence the size of the mass when it becomes critical will be determined by, among other things, the core shape.  Perhaps a mixing blade like those seen in household washing machines will be useful to spin the molten solution to force precipitates to the extreme walls of the core in order to procure a rapid shutdown of the reaction.  Another possibility is to use a venturi-vacuum to collect and direct precipitants into a zone of close proximity wherein a critical mass is obtained so long as the shape is supported by action rather than inaction; any pump failures would therefore result in the collapse of the critical mass- a feature which proclaims safety first."

Concluding Remarks
If the ANFR were in operation today, which it is not, and if this technology were shared abroad, it is likely that this reactor scheme would pose special difficulties to those wishing to abstract bomb-making materials.  In the language of the APS study group on nuclear fuel cycles and waste management,25 both physical security barriers and technical barriers would be lifted against the theft and subsequent use of special nuclear materials.  Given a closed loop or in situ fuels reprocessing and power reactor system, such as the ANFR, terrorists and others seeking nuclear materials would likely find it easier to steal raw nuclear fuel (such as U02-C) than to extract high temperature nuclear fuels from an operating system that need not be shut down for re-fueling.  Faced with the technical barriers of extracting the small percentage of U-235 from U-238 in a U02-C system or otherwise, it is highly improbable that any terrorist or sub-national group could accomplish the task let alone accomplish the task undetected.  These same barriers would discourage countries party to the Nuclear Proliferation Treaty from obtaining nuclear bomb materials from an ANFR power reactor.
However, countries desiring to obtain nuclear weapons will likely do so by some other means, such as through black market purchases, or independent and unmonitored (by the International Atomic Energy Agency) research" reactors and reprocessing facilities (or enrichment facilities- either by conventional means or by centrifugation or through the application of lasers).  Nuclear weapons knowhow is already largely out of the bag," and all precautions must be taken to slow the unavoidable proliferation of nuclear weapons.  Is the ANFR the solution? Perhaps it cannot be developed and deployed soon enough to moderate the spread of nuclear weapons to more countries than already having the bombs.  But surely it offers good prospects for severely limiting the loss of special nuclear materials to terrorists and sub-national groups.  Further attention must be given to this innovative new reactor scheme, and in general, to the prospect of in situ reprocessing of spent nuclear fuels in any reactor scheme.

 

Notes
I would like to express appreciation for the research direction provided by Dr. George A. Williams, University of Utah, and for research summaries and comments provided by Dr. Norman A.D. Parlee, Stanford University.

Rogers, Benjamin T. (1979:3).  Microclimate: Don't Fight the Site," The Solar Age Resource Book.  New York:  Everest House.

Jones, Robert R., ed., (1976:55-58, 55-56).  Meet the ANF Reactor," Industrial Research, Vol. 18 No. 5, May.

O'Toole, James (1978:xiv-xv).  Energy and Social Change.  Cambridge, Mass.:  The M.I.T. Press.

Hoyle, Fred and Geoffrey (1980:68, 71).  Commonsense in Nuclear Energy.  San Francisco: W.H. Freeman and Co.

Wiesner, Jerome B. and York, Herbert F. (1964:3).  National Security and the Nuclear-Test Ban," Scientific American, Vol. 211 No. 4 (Oct.), reprint.

Epstein, William (1980:196, 207-209).  The Proliferation of Nuclear Weapons," in Energy and Environment, ed. Raymond Siever.  San Francisco: W.H. Freeman and Co.

Siever, Raymond, ed. (1980:194).  Energy and Environment.  San Francisco: W.H. Freeman and Co.

Stimson, Henry L. (1976:172).  The Decision to Use the Atomic Bomb," in Public Administration:  Concepts and Cases, ed. by Richard J. Stillman II.  Boston: Houghton Mifflin Co.

Rose, David J. and Lester, Richard K. (1980:213-225).  Nuclear Power, Nuclear Weapons, and International Stability," in Energy and Environment, ed. by R. Siever.

Chayes, Abram (1976:30, 30-32).  Nuclear Arms Control After the Cold War," in Arms, Defense Policy and Arms Control, ed. by Franklin A. Long and George W. Rathjens.  New York:  W.W. Norton & Co.

Agnew, Harold M. (1981:56, 55-57, 56).  Gas-Cooled Nuclear Power Reactors," Scientific American, Vol. 244 No. 6, June.

Inglis, David R. (1973:178-183).  Nuclear Energy:  Its Physics and Its Social Challenge.  Reading, Mass.:  Addison-Wesley Publishing Co.

Frauenfelder, Hans and Henley, Ernest M. (1974:456-459).  Subatomic Physics.  Englewood Cliffs, N.J.:  Prentice Hall.

Davis, David H. (1978:189).  Energy Politics 2nd Ed.  New York:  St. Martin's Press.

Reviews of Modern Physics (1978), Vol. 50, No. 1, Part II, January, p. S18.

Parlee, N.A.D., Stanford University, Selective Nitriding and Carbothermic Reduction in Liquid Solvent Metals," unpublished research summary, p. 3.

Anderson, R.N. and Parlee, N.A.D. (1971:1599).  Nitrogen-Nitride Reactions in Molten U-Sn Alloys," Metallurgical Transactions, Vol. 2, June.

Anderson, R.N., et al. (1972:29,32).  Application of Nitride-Forming Reactions To Reprocessing of Spent Nuclear Fuels," Nuclear Technology, Vol. 13, January.

Anderson, R.N., and Parlee, N.A.D. (1972:298,298-299).  Continuous Removal of Fission Products In A Nitride-Fueled Reactor," Nuclear Technology, Vol. 13, March.

Anderson, R.N. and Parlee, N.A.D. (1976:526-529).  Carbothermic Reduction of Refractory Metals," Journal of Vacuum Science and Technology, Vol. 13, No. 1, January/February.

Bakshuni, N., et al. (1979:126).  A New Carbothermic Process," Industrial Research Development, Feb.

Cohen, Bernard L. (1977:21-31).  The Disposal of Radioactive Wastes from Fission Reactors," Scientific American, Vol. 236, No. 6, June.

 *Note on space-walker economy- see R.D. Green and William D. Ohlsen, Solar Energy: An Overview," in Energy And The Future: Part I, (by R.D. Green) University of Utah, Correspondence Study, 1984.

 

About the Author
R. Don Green received a Ph.D. from the University of Pennsylvania and served as a Post-Doctoral Fellow at the faculty rank of Research Engineer in the School of Engineering and Applied Science, Systems (dept.).