Nuclear material

“ Our early nuclear explosives have used fission. In the fission process a great array of radioactive products are formed, some of them intensely poisonous. More recently we have learned how to produce energy by fusion. Fusion produces fewer and very much less dangerous radioactivities. Actually the neutrons which are a by-product of the fusion reaction may be absorbed in almost any material and may again produce an assortment of radioactive nuclei. However, by placing only certain materials near the thermonuclear explosion, one may obtain a weapon in which the radioactivity is harmless. ”

“ If a unit charge is accelerated through a potential difference of one volt, it acquires an energy of one electron-volt. The energies required for nuclear bombardment are of the order of several million electron-volts, which can be provided by atom-smashing machines such as the cyclotron.
Even at such high energies very few of the nuclear projectiles actually find their way to a target nucleus. Most of them are slowed down by the electrons, wasting their energy in heating up the target material. Perhaps one particle out of a million will be lucky enough to induce a nuclear reaction. ”

“ We hear that nuclear power will act in its place, but then nuclear power cannot be used as the raw material for manufactured articles, and even in the field of energy it is said that, if we do not have an amount of petroleum which corresponds to one-fourth the energy gained from nuclear power, it is impossible to operate the nuclear power plants. ”

“ A trained nuclear engineer with an amount of highly enriched uranium or plutonium about the size of a grapefruit or an orange, together with commercially available material, could fashion a nuclear device that would fit in a van like the one Ramzi Yousef parked in the garage of the World Trade Center in 1993. ”

“ There is no reason why one should not use a cold target material, which is bombarded from the outside by energetic nuclear projectiles, for example protons or alpha particles. The projectiles, if they are energetic enough, can overcome the electrical repulsion of the target nuclei, and they actually can penetrate. ”

“ Today, as I see it, we are facing far different dangers, including the rise in the number of nuclear weapon states and the number of states that can produce weapon-grade material. Another key ingredients is not simply the weapons, it’s the weapons-grade material. ”

“ The point is that a neutron born in a nuclear reaction must travel on the average a certain distance before it can produce another reaction. If the size of the chain-reacting material is much less than this distance, practically all of the neutrons produced will be able to escape through the material surface, and no chain reaction will be possible. If the size of the material is large compared to this distance, the leakage loss becomes negligible, and the possibility of a chain reaction depends entirely on the magnitude of the first kind of loss, the wasteful captures in nuclei. ”

“ Then, in March 1941, the element plutonium was isolated, and the plutonium-239 isotope was found to fission as readily as the scarce uranium isotope, uranium-235. The plutonium, produced in a uranium-fueled nuclear reactor, provided the United States with an additional source of material for nuclear weapons (7; 12) .
In the summer of 1941, the British Government published a report written by the Committee for Military Application of Uranium Detonation (MAUD) . This report stated that a nuclear weapon was possible and concluded that its construction should begin immediately. ”

“ The great mobility of nuclear firepower makes it highly probable that the nuclear conflict will be short. What the factory produces during this conflict will not affect the outcome of the fighting. The only weapons on which anyone can rely are 142 the weapons which are already stockpiled. Therefore, it will be militarily useless to bomb factories.
The same fact of mobility also implies that no great flow of war material will need to be maintained. Practically all movement can be executed by light and fast methods, by planes, submarines, and small battle groups. ”

“ While we are focusing with justified concern on Iran and North Korea’s quest for nuclear weapons capacity, a number of nations, some of them our good friends, are planning to go into the enrichment and/or reprocessing business, and that conversion means making material for nuclear power. But when you start enriching, it’s very difficult to tell when you move from a nuclear power level of enrichment, which I believe is about four percent, to a 70 to 75 percent enrichment, which can blow up a lot of the world. ”

“ No reviewer recommended a focused federally funded program for low energy nuclear reactions.
Reviewers identified two areas where additional research could address specific issues. One is the investigation of the properties of deuterated metals including possible effects of alloying and dislocations. These studies should take advantage of the modern tools for material characterization. A second area of investigation is the use of state-of-the-art apparatus and techniques to search for fusion events in thin deuterated foils. ”

“ Radiological dispersal devices, comprised of an explosive device with radioactive material, can be detonated without the need for the components of a nuclear weapon. The RDD can disperse radioactive material over an area of the battlefield causing effects from nuisance levels of radioactive material to life-threatening levels without the thermal and, in most cases, the blast effects of a nuclear detonation. For nuclear weapons effects see Appendix A.
[1-3] Table 1-1. Countries Possessing or Suspected of Possessing Nuclear Weapons
b. ”

“ In order to detonate a nuclear weapon, an adversary must first obtain access to the appropriate weapons-grade material. However, an RDD can be produced and used by anyone with access to industrial or medical radioisotopes and explosives. ”

“ After requesting the opinion of the Economic and Social Committee, the Commission may, within the framework of the Joint Nuclear Research Centre, set up schools for training specialists, particularly in prospecting for ores, producing nuclear materials of a high degree of purity, processing irradiated fuels, in atomic engineering, health protection and the production and use of radioactive isotopes. ”

“ This can, for obvious reasons, lead to serious instability in the overall system—most interesting systems cannot withstand the unbounded increase of any of their parameters without serious negative consequences. The basic engineering principles underlying the creation of nuclear weapons exploit this feature of positive feedback mechanisms: the destructive output of nuclear weapons results from the energy released during the fission of certain isotopes of (in most cases) uranium or plutonium. ”

“ Only a few, relatively rare, naturally occurring substances -- primarily Uranium-235 -- can maintain the nuclear fission chain reaction necessary for operation of these [p1083] reactors. There are thus severe constraints on the long run potential of nuclear energy for generating electricity unless new nuclear fuel is "artificially" produced. ”

“ Our sources of energy are not yet nuclear sources. Even in the military field, where development has been most rapid, the structure of the armed forces has not yet adjusted itself to the facts of the nuclear age in a realistic manner. ”

“ It has now been two decades since the introduction of thermonuclear fusion weapons into the military inventories of the great powers, and more than a decade since the United States, Great Britain, and the Soviet Union ceased to test nuclear weapons in the atmosphere. Today our understanding of the technology of thermonuclear weapons seems highly advanced, but our knowledge of the physical and biological consequences of nuclear war is continuously evolving. ”

“ The HEU Agreements provide for the conversion of approximately 500 metric tons of highly enriched uranium contained in Russian nuclear weapons into low-enriched uranium for use as fuel in commercial nuclear reactors. ”

“ Plans for other nuclear-powered desalting projects around the world are being discussed by the United States government, the International Atomic Energy Agency and the governments of many other nations. ”

“ The U. S. is not alone in its use of nuclear energy as a tool of science. The United Kingdom has carried out radiological studies of the marine environment for many years, particularly concentrating on the effects of radionuclides from nuclear power plants on the sea immediately contiguous to the British Isles. Both the European Atomic Energy Community and the International Atomic Energy Agency also encouraged marine radiological studies. ”

“ In politics the atomic nucleus has entered as a promise and as a menace—not as a fact on which we can build and with which we can reckon.
Some technical predictions seem safe:
Nuclear energy will not render our older power plants obsolete in the near future. But nuclear energy will make it 169 possible to maintain the pace—even the acceleration—of the industrial revolution. It will be possible to produce all the energy we need at a moderate cost. Furthermore—and this is the important point—this energy will be available at any place on the globe at a cost which is fairly uniform. ”

“ If a chain reaction could be started in a sizable piece of uranium, unimaginable quantities of energy would be produced. Just 1 gram of uranium, undergoing complete fission, would deliver the energy derived from the total burning of 3 tons of coal and would deliver that energy in a tiny fraction of a second.
Szilard, who had come to the United States in 1937, clearly visualized the tremendous explosive force of something that would have to be called a “nuclear bomb”. ”

“ These conditions are ideal for the production of tremendous amounts of NO from the air. It has been estimated that as much as 5,000 tons of nitric oxide is produced for each megaton of nuclear explosive power. ”

“ In western Europe and North America, which today have almost 75 per cent of current world capacity, nuclear provides about one-third of the energy that was forecast for it 10 years ago. Apart from Fance, Japan, the USSR, and several other East European countries that have decided to continue with their nuclear programmes, ordering, construction, and licensing prospects for new reactors in many other countries look poor. ”

“ We will also ensure that these developing nations have a reliable nuclear fuel supply. In exchange, these countries would agree to use nuclear power only for civilian purposes and forego uranium enrichment and reprocessing activities that can be used to develop nuclear weapons. ”

“ The industrial policy of actively exploiting nuclear energy has been formulated and issued, which has effectively secured the growth of the industries of nuclear power, nuclear fuel recycling, and nuclear technology application. ”

“ Nuclear fuel even today is no more expensive than conventional fuel in many parts of the United States. Nuclear fuel is neither heavy nor bulky and can be therefore transported easily. In those parts of the world where ordinary fuel is expensive, nuclear energy will soon become of great importance. Furthermore, we shall learn to use most of the energy in uranium rather than just the part contained in its rare and valuable isotope, U235. ”

“ One only has to add a neutron to common U238 to get radioactive U239. In the course of time this decays into plutonium. This element can be used like U235: It produces fission, a great amount of energy and enough neutrons to keep the process going. We shall also learn to extract energy from other nuclear fuels. Thorium acts like uranium, while deuterium can give energy by building up bigger nuclei rather than breaking them into smaller pieces. Therefore the source of energy will be universally available and quite inexpensive. ”

“ Both the local and worldwide fallout hazards of nuclear explosions depend on a variety of interacting factors: weapon design, explosive force, altitude and latitude of detonation, time of year, and local weather conditions.
All present nuclear weapon designs require the splitting of heavy elements like uranium and plutonium. The energy released in this fission process is many millions of times greater, pound for pound, than the most energetic chemical reactions. ”

“ ATOMS, NATURE, and MAN
Man-made Radioactivity in the Environment
by Neal O. Hines
The Understanding the Atom Series
Nuclear energy is playing a vital role in the life of every man, woman, and child in the United States today. In the years ahead it will affect increasingly all the peoples of the earth. It is essential that all Americans gain an understanding of this vital force if they are to discharge thoughtfully their responsibilities as citizens and if they are to realize fully the myriad benefits that nuclear energy offers them. ”

“ If such a reactor operates for half a year and then explodes and releases its radioactive content into the atmosphere, its radioactivity will be comparable to that of a hydrogen bomb. In one important respect such an accident would be worse than a hydrogen explosion. The nuclear explosive lifts most of its radioactive products to a high altitude and the poisonous activity gets dispersed and diluted before it descends. The activity from a reactor on the other hand will remain close to the ground and might endanger the lives of the people in an area of hundreds of square miles. ”

“ If we find—and others also find—that clean weapons are the most desirable, the total strontium contamination is not likely to become more than perhaps two to four times the present value. We believe that all reasons—respect for human life, military considerations and simple sanity—lead to one conclusion. In the development of nuclear explosives we must endeavor to make them clean. But the real reason for this does not lie in the small contamination due to tests. The real reason is that war could turn contamination into a danger to countless people. ”