Species, transmutation

Darwin occasionally uses the term transmutation for change in species, as in his notebook B, where he employs transmutation of Species for the title and refers to transmutation in the text. See Charles Darwin s Notebooks 1836-1844, ed. Paul H. Barrett et al. (Ithaca Cornell University Press, 1987), 7,227. For a vivid description of the composition of this important notebook, where Darwin develops his own theory of species transmutability, see Adrian Desmond and James Moore, Darwin (London Penguin, 1992), 229-239. For Darwin s analogy between artificial and natural selection, see Charles Darwin, On the Origin of Species, ed Ernst Mayr (Cambridge, MA Harvard University Press, 1964), 7-43. 

Ernst Mayr, Joseph Gottlieb Kolreuter s Contributions to Biology, Osiris, 2d ser., 2(1986), 135—176, especially 135. For another recent treatment of Kolreuter s work on species transmutation and its reception, see James L. Larson, Interpreting Nature The Science of Living Form from Linnaeus to Aim/(Baltimore Johns Hopkins University Press, 1994), 70—78. 

Robert Olby, Origins of Mendelism (Chicago University of Chicago Press, 1985), 17 [Kolreuter s] final and most convincing proof ofbiparental heredity was his famous species transmutations. ... 

But let us suppose, for the sake of argument, that Kolreuter did not receive his exposure to the Aristotelian dogma against species transmutation directly from the alchemical authors themselves. Here too an interesting... 

The new elements neptunium and plutonium have been produced in quantity by neutron bombardment of uranium. Subsequently many isotopes have been obtained by transmutation and synthetic isotopes of elements such as Ac and Pa are more easily obtained than the naturally occurring species. Synthetic species of lighter elements, e.g. Tc and Pm are also prepared. 

Potential fusion appHcations other than electricity production have received some study. For example, radiation and high temperature heat from a fusion reactor could be used to produce hydrogen by the electrolysis or radiolysis of water, which could be employed in the synthesis of portable chemical fuels for transportation or industrial use. The transmutation of radioactive actinide wastes from fission reactors may also be feasible. This idea would utilize the neutrons from a fusion reactor to convert hazardous isotopes into more benign and easier-to-handle species. The practicaUty of these concepts requires further analysis. 

In the earlier sections, we have developed the theoretical framework for the FEP approach. In this section, we outline some specific methodologies built upon this framework to calculate the free energy differences associated with the transformation of a chemical species into a different one. This computational process is often called alchemical transformation because, in a sense, this is a realization of the inaccessible dream of the proverbial alchemist - to transmute matter. Yet, unlike lead, which was supposed to turn into gold in the alchemist s furnace, the potential energy function is sufficiently malleable in the hands of the computational chemist that it can be gently altered to transform one chemical system into another, slightly modified one. 

Today, physical chemistry has accomplished its great task of elucidating the microcosmos. The existence, properties and combinatory rules for atoms have been firmly established. The problem now is to work out where they came from. Their source clearly lies outside the Earth, for spontaneous (cold) fusion does not occur on our planet, whereas radioactive transmutation (breakup or decay), e.g. the decay of uranium to lead, is well known to nuclear geologists. The task of nuclear astrophysics is to determine where and how each species of atomic nucleus (or isotope) is produced beyond the confines of the Earth. 

Ambivalence, as we use this term in everyday speech, has no place in modern science. Even premodern science seems troubled by ambivalence. For if gold can be transmuted from base metals, this must mean that it can be transmuted back into base metals. The Renaissance philosopher-critic Benedetto Varchi cites Aristotle on the generation of species as an argument against the truth of alchemy " ... 

It has been known for many years that the fission products observed in the field or in the laboratory some time after the event are in fact not usually the species produced in fission at all but the result of one or several consecutive beta disintegrations of shorter lived isobaric precursors which are formed directly in the fission process. From the chemist s point of view this is important because the f -decay process is an actual transmutation of elements, and the time scale involved is frequently comparable with that for the formation of fallout particles. 

ATOMIC SPECIES. A distinctive type of atom. The basis of differentiation between atoms is (1) mass, (2) atomic number, or number of positive nuclear charges, (3) nuclear excitation energy. The reason for recognizing this third class is because certain atoms are known, chiefly among those obtained by artificial transmutation, which have the same atomic (isotopic) mass and atomic number, but differ in energetics. 

When using an HDCC accelerator, the required electric potential for having the same nuclear events is dramatically reduced. Note that for the maximum reaction rates for the D-D nuclear events, the maximum occurs at about 272 Volts (lower x-axis label). Some of the desired nuclear reactions to stabilize (transmute) specific highly radioactive species into stable elements will, of course, require that the combined HDCC be accelerated using potentials up to 70 keV. 

Ihe transmutation of one elemental species into another by radioactive decay is a phenomenom that will certainly influence the behavior of stored radioactive waste, but transmutation has received little attention in this context. Although the cause can... 

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