Introduction to the Actinides

The symposium was designed to provide an overview of the current status of plutonium chemistry by practitioners in the various areas covered. The authors, drawn from U.S. and foreign universities and national laboratories, were encouraged to include review material to place their subjects in perspective, as well as to suggest what they believe to be productive directions for future investigation. We find it particularly useful that the contributions represent a mixture of fundamental as well as more applied environmental and process chemical research. Although we do not claim that this volume represents all areas of plutonium chemistry that are currently under active investigation, this collection does represent a reasonably broad and balanced view of the field. The contents of the volume should be useful as a reference both for those familiar with actinide chemistry and for those with limited interests who seek an introduction to the literature and current status in an area of plutonium chemistry. 

A general introduction to the chemistry of POMs [1] and more recent reviews [2,3,7] illustrate the broad range and potential scope of this field. The present article concentrates on the structural chemistry of polyoxometalates which incorporate actinide (An) elements as heteroatoms. A review of actinide... 

S.A. Cotton (1991) Lanthanides and Actinides, Macmillan, London - A good general introduction to the /-block elements. 

A good introduction to the subject of ion exchange in the actinides is contained in... 

It should be noted that the late-actinide hydrides react more easily and vigorously than any of the rare-earth counterparts. This effect, which is kinetic and not thermodynamic, is discussed in section 5. As an introduction to the new data and information to be presented, comparative trends for the rare-earth and late-actinide hydrides are summarized in table 1. It should be understood that MHj simply implies a value at or near the phase boundary and that the temperature of the measurement is not unambiguously defined. For most systems, the phase-boundary composition is near... 

Because of the corrosiveness and moisture-sensitivity of superacids and actinide and rare-earth compounds treated with these materials, some introduction to the experimental details of this area of chemistry is warranted. Interested persons are urged to consult such standard textbooks as the one by Shriver and Drezdzon (1986). 

Gnillanmont R, Bouissieres G, Muxart R (1968) Chimie du Protactinium. I. Solutions aqueuses de protactinium penta- et tetravalent. Actinides Rev 1 135-163 Harvey BG (1962) Introduction to Nuclear Physics and Chemistiy. Prentice Hall Inc, New Jersey Henderson GM, Anderson RF (2003) The U-series toolbox for paleoceanography. Rev Mineral Geochem... 

Before introduction into the spectrometer, a mechanical and/or electrochemical polishing of the sample surface has to be performed. While a good empirical knowledge has been gained for most current materials the right procedure to follow in the case of actinide compounds is still not well established. 

It should be noted that two phenomena that are important for the theory of magnetism and that are relevant to the present discussions are not treated at all. These phenomena are magnetic anisotropy and magnetostriction. Also there is no discussion of the rare earth and actinide metals or compounds, for which much of the present discussion serves as a necessary introduction. 

The introduction of the permethyl substituted cyclopentadienyl ligand into the coordination sphere of actinides afforded complexes with advantageous solubility, crystallizability, thermal stability, and resistance to ligand redistribution. However, abundant structural data indicate that despite these advantages the metal center suffers from a high steric congestion that may decrease... 

The preliminary investigation showed that introduction of minor actinides in fuel results in great increasing of sodium void reactivity effect (SVRE) and therefore the using of traditional fast reactors is impossible because it isn t possible to assure zero value of SVRE which is dictated by Russia Safety... 

In first case the introduction, of minor actinides doesn t influence on core physical parameters and efficiency of its burning is 30 kg/TW hour. When we use the core with increased plutonium enrichment the efficiency can be increased up to 32 kg/TW hour. 

The application of powder metallurgical techniques using mixtures of the elements or the metal hydride and graphite have resulted in relatively pure carbides of various compositions. This is a particularly useful method when defective compounds in Groups 5 and 6 are needed. The powdered metals or hydrides in Group 4 and the actinide series are sufficiently reactive to air that the introduction of oxygen is hard to avoid. 

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