Neptunium chemistry is covered in this lecture. Nuclear properties and synthesis of neptunium are described, with emphasis placed on the isotopes 235-239Np. The synthesis and properties of neptunium metal, alloys, and intermetallic compounds are introduced. The lecture describes neptunium compound synthesis, with resulting thermodynamic and structural properties provided. Neptunium organometallic and coordination compounds are also presented. Information on neptunium solution speciation, redox, and spectroscopy is given, with trends based on oxidation state examined. A presentation of analytical methods useful in neptunium chemistry, including Mössbauer spectroscopy, concludes the lecture. Comparisons are made with uranium chemistry to provide trends in the actinides.
Wednesday, June 25, 2014
Lecture 11: Uranium chemistry
This lecture is in two parts. Uranium chemistry is covered in this lecture with an emphasis on separations and synthesis for the nuclear fuel cycle. Uranium is introduced with an overview of its chemistry for the fuel cycle. The solution chemistry of uranium is explored, focusing on uranyl. The molecular orbital of uranium is described. Separation of uranium by solvent extraction and ion exchange is presented. The enrichment of uranium from the uranium hexafluoride species is discussed, including diffusion, centrifuge, and laser methods. Oxide species of uranium are presented. Due to its potential as a nuclear fuel, the synthesis and properties of uranium metal and alloys are described in detail. With three different phase, the uranium metal exhibits more complex electronic behavior than the metals of the lighter actinides, a trend that continues to plutonium metal.
Saturday, June 21, 2014
Lecture 10: Speciation
This lecture covers fundamentals of chemical kinetics thermodynamics, mainly as a review. Emphasis of the lectures is applied to information useful for speciation modeling. Equilibrium constants are discussed. The role of chemical activity is provided. Calculations and models for speciation are presented. Equilibrium modeling using EXCEL and the program CHESS are presented. Solubility calculations are provides, with examples for the uranium system.
Lecture 9: Nuclear Reactions
The lecture on nuclear reactions is presented in two parts. Nuclear reaction notation is introduced. The role of energetics in nuclear reactions is discussed and evaluated, including Q value, reaction barriers, and threshold energy. Center of mass and laboratory frames are discussed. The different processes involved in the formation of isotopes is provided including photonuclear processes. Reaction energetics, mechanisms and types are described. Nuclear reaction cross sections are described, with a presentation on values and limits given. This includes role of angular momentum in cross section values. The stellar production of elements is presented in terms of nuclear reactions. These provide the basis for understanding the formation of isotopes in stars.
Quiz 2: Beta Decay, Gamma Decay, Fission, Nuclear Models
Quiz 2 is posted. It was assigned 20 June 2014 and is due 27 June 2014. There will be office hours for the quiz at 4:45 PM,
Thursday 26 June, 4th floor HRC. The quiz covers:
Lecture 5: Beta Decay
Lecture 6: Gamma Decay
Lecture 7: Fission
Lecture 8: Nuclear Models
Use lecture notes, textbooks, Chart of the Nuclides, Table of the
Isotopes, and web pages. Show your work
or reference. If you use a spreadsheet
please include what equations you used to solve the problem.
Wednesday, June 18, 2014
Lecture 8: Nuclear Force and Nuclear Models
This lecture provides information on nuclear force and nuclear models. The strong force is introduced through isospin. A comparison of exchange particles is provided. The use of mirror nuclei to examine the strong force is presented. An overview of nuclear potentials is provided and used as a basis of the shell model. States of the shell model and their relationship to magic numbers are discussed. Use of the shell model is determine nuclide spin and parity is presented. From the shell model the unpaired nucleon is used to assess overall nuclear spin. Examples are provided for nuclei with one or two unpaired nucleons. Nordheim rules are used to evaluation spin and parity with odd-odd nuclei. The relationship between spin and parity with nuclear deformation is introduced with Nilsson diagrams. Additional information on Nilsson diagrams can be found in the Table of the Isotopes. An introduction of the Fermi model for energetic nuclei is given.
Monday, June 16, 2014
Lecture 7: Fission
A general overview of nuclear fission is presented. The probability of fission is described based on developed models including the liquid drop model and shell corrections. Discussion on spontaneous fission and fissioning isomers is given. The transition nucleus and fission product distributions are discussed. The total kinetic energy, mass distribution, and charge distribution during fission are presented. Changes in fission product distribution with parent properties are introduced. Delayed neutrons from fission and their role in reactors are given. Proton induced fission is introduced.
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