CHEM 418 Nuclear Chemistry, Winter 2016: Lecture 18 Nuclear Forensics

This lecture covers the utilization of radionuclides and introduces signatures resulting from these activities. Signatures from reactors are  introduced. Specific details are provided on forensic signatures related to Pu and actinide isotopics. This lecture is not assigned but can be viewed for additional information.

CHEM 418 Nuclear Chemistry Winter 2016 Exam 3

Assigned: 3-Mar-16                                                               

1st Due Date: 8-Mar-16

2nd Due Date:  11-Mar-16                                                                         

Lecture 11:  Speciation

Lecture 12:  Uranium chemistry

Lecture 13:  Neptunium chemistry

Lecture 14:  Plutonium chemistry

Lecture 15:  Americium and Curium chemistry
Lecture 16:  Chemistry in reactor fuel

Lecture 17:  Separations

Use lecture notes, textbooks, Chart of the Nuclides, Table of the Isotopes, and web pages.  Use the chart of the nuclides as your primary dataset for isotope half-life.   Show your work or references on a separate page and save electronically.  Submission of the work is not required for the 1st due date.  Please use 3 significant digits for your answers.  For scientific notation please use X.XXEX (i.e, 1230 as 1.23E3).

The first iteration of the exam is due 8-Mar-16.  The answers will be posted on 9-Mar-16.  Any incorrect answers can be resubmitted by 11-Mar-16. Changed answers will be worth 50 % of the original grade.  For the 2nd resubmission the work related to the changes must be shown.  Please post all questions to the blog.

CHEM 418 Nuclear Chemistry, Winter 2016: Lecture 17 Separations

A number of different separation methods for radionuclides, with an emphasis on actinides, are presented. Solvent extraction, ion exchange, electrochemical, volatility and ionic liquid methods are discussed. The fundamental concepts are provided with specific examples on the nuclear fuel cycle. Ideas and concepts for advanced separations are given. Details are provided for the different separation routes discussed. The PUREX process is described. Examples are given for TRUEX and TALSPEAK separations. Specific examples for actinide separations are provided. Part 4 is a summation lecture on transuranic separations that are drawn from the Np, Pu, Am, and Cm lectures. Part 4 is meant as a review and provides a compilation of separation methods, the bulk can be skipped, but examples of questions are provided at the end of the lecture. 

CHEM 418 Nuclear Chemistry, Winter 2016: Lecture 16 In reactor chemistry

This lecture describes the chemistry of actinides and fission products in reactors, primarily focusing on phases formed in nuclear fuel. The fission process is reviewed and fuel burnup discussed. Determining fission product and actinide concentration to assess burnup is introduced. The variation of fission product and actinide concentration with burnup and initial fuel composition is provided. Axial and radial distribution of activity, fission products, and actinides is discussed, highlighting the role of neutron flux and energies on the distribution. Conditions necessary for the formation of separate phases in UO₂ are shown for perovskite and metallic phases, emphasizing the role of oxygen in the process. The behavior of fission products can be grouped into 4 areas: volatile species, metallic precipitates, oxide precipitates, and solid solutions.

CHEM 418 Nuclear Chemistry, Winter 2016: Lecture 15 Americium and Curium Chemistry

This lecture introduces the chemistry of americium and curium. Both elements are discussed due to their similar chemical behavior, particularly in separations. However, important differences in their chemistry are highlighted. For americium pentavalent and hexavalent species are achievable. For curium, its unique fluorescence properties are highlighted. The nuclear properties of americium and curium isotopes are provided. Isotope production focus on those formed from multiple neutron capture. These isotopes, ²⁴¹Am, ²⁴³Am, ²⁴⁴Cm and ²⁴⁸Cm, are used to explore americium and curium chemistry. The basic solution chemistry is described, along with implications for fuel cycle separations. Methods for the separation of americium and curium are provided, including solvent extractions, anion exchange, precipitation, and molten salt techniques. Synthesis and characterization of americium and curium metals, alloys, and compounds are provided, with emphasis placed on those compounds of importance to the nuclear fuel cycle. The non-aqueous and coordination chemistry of these elements are introduced. The limited available data offers an avenue for novel explorations and future research directions.

CHEM 418 Nuclear Chemistry, Winter 2016: Lecture 14 Plutonium Chemistry

This lecture provides basic information on the chemistry of plutonium.  Discussion on the nuclear properties of 238Pu and 239Pu are included.  Environmental concentrations of plutonium, including244Pu and naturally produced 239Pu, are discussed.  Large scale plutonium separations are presented, emphasizing the PUREX (Links to an external site.)process.  The use of volatility and ion exchange as plutonium separation techniques are also given.  The synthesis and properties are metallic plutonium are described in detail.  An review of metal preparation methods are provided, including the plutonium-gallium phase diagram. The physical properties of plutonium metal are given and discussed. The solution chemistry of plutonium is depicted though coordination and spectroscopy as a function of oxidation state.  Examples are provided on various nature of plutonium chemistry in the tributylphosphate-nitric acid system and colloids.  The non-aqueous chemistry of plutonium is described and related to electronic structure.  

CHEM 418 Nuclear Chemistry, Winter 2016: Lecture 13 Neptunium Chemistry

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.  

The PDF Quiz for lecture 13 contains a signature box.  This is a new addition to the quizzes.

CHEM 418 Nuclear Chemistry, Winter 2016: Lecture 12 Uranium Chemistry

Uranium chemistry is covered in this lecture with an emphasis on separations and synthesis for the nuclear 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.

CHEM 418 Nuclear Chemistry, Winter 2016: Lecture 11 Speciation

This lecture covers fundamentals of chemical kinetics and thermodynamics, mainly as a review. The thermodynamic discussion relates to Gibbs free energy and equilibrium constants. Kinetic discussion related to its use in data analysis Emphasis of the lectures is applied to information useful for speciation modeling.  Calculations and models for speciation are discussed. Equilibrium modeling using EXCEL and the program CHESS (Links to an external site.) are presented.

CHEM 418 Nuclear Chemistry Winter 2016 Exam 2

Exam 2

Exam 2 Answers

Assigned 11-Feb-16

1st Due Date: 16-Feb-16

2nd Due Date:  19-Feb-16                                                            

Lecture 6:  Gamma Decay

Lecture 7:  Fission

Lecture 8:  Nuclear Force and Nuclear Structure

Lecture 9:  Nuclear Reactions

Lecture 10:  Radiation Interactions

The first iteration of the exam is due 16-Feb-16.  The answers will be posted on 17-Feb-16.  Any incorrect answers can be resubmitted by 19-Feb-16. Changed answers will be worth 50 % of the original grade.  For the 2nd resubmission the work related to the changes must be shown.  Please post all questions to the blog.

Use lecture notes, textbooks, Chart of the Nuclides, Table of the Isotopes, and web pages.  Use the chart of the nuclides as your primary dataset for isotope half-life.   Show your work or references on a separate page and save electronically.  Please use 3 significant digits for your answers.

CHEM 418 Nuclear Chemistry, Winter 2016: Lecture 10 Radiation interactions

This lecture, in 2 parts, covers interaction of radiation with matter and includes fundamental interactions, particle ranges, dosimetry, and hot atom chemistry. Interaction of radiation with matter covers energy loss and reactions with charged particles and photons. The stopping power of charged particles in different material is covered, including calculations on energy loss with thickness. Electron backscattering is introduced with examples on different behavior with varied elements. Discussion on photon interaction includes photoelectric effect, Compton effect, and pair production. Units of dosimetry are described. Dosimetry measurements are discussed and quality factors based on particle mass and charge are introduced. Introductory dose calculations are supplied. Radiation protection regulations and the definition of terms (ALI, DAC) are given. A review of hot atom chemistry is given.

CHEM 418 Nuclear Chemistry, Winter 2016: 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. 

CHEM 418 Nuclear Chemistry, Winter 2016: 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 to discuss 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. 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.

CHEM 418 Nuclear Chemistry, Winter 2016: 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. 

CHEM 418 Nuclear Chemistry, Winter 2016: Lecture 6 Gamma Decay

Gamma decay is described in two lectures. The first lecture covers the fundamentals of gamma decay and second lecture describes Moessbauer spectroscopy.  Different methods to find data on gamma decay yields for decay of isotopes are presented. The energetics involved in gamma decay are provided. This includes recoil from gamma, which is exploited in Moessbauer spectroscopy.  Decay types in gamma transitions are explained, focusing on electromagnetic basis for the gamma emission.  Transition probabilities and internal conversions inherent to gamma decay are covered. Isotope examples for internal conversion electrons are given.  Angular correlations in gamma decay are described with an experimental example provided. The use of gamma decay in Moessbauer spectroscopy is discussed.

CHEM 418 Nuclear Chemistry Winter 2016 Exam 1

EXAM 1 is now available

Assigned: 21-Jan-16 

1st Due Date: 26-Jan-16                  

2nd Due Date:  29-Jan-16      

The first iteration of the exam is due 26-Jan-16.  The answers will be posted on 27-Jan-16.  Any incorrect answers can be resubmitted by 29-Jan-16. Changed answers will be worth 50 % of the original grade.  For the 2nd resubmission the work related to the changes must be shown.  Please post all questions to the blog.

There will be office hours on Friday 22 January and Tuesday 26 January.  This quiz covers:                                 

Lecture 1:  Introduction, Chart of the Nuclides

Lecture 2:  Nuclear Properties

Lecture 3:  Decay Kinetics

Lecture 4:  Alpha Decay

Lecture 5:  Beta Decay

 Use lecture notes, textbooks, Chart of the Nuclides, Table of the Isotopes, and web pages.  Use the chart of the nuclides as your primary dataset for isotope half-life.   Show your work or references on a separate page and save electronically.  Please use 3 significant digits for your answers.

CHEM 418 Nuclear Chemistry, Winter 2016: Lecture 5 Beta Decay

Beta decay is presented in this lecture. The neutrino hypothesis and its relationship with beta decay is discussed. A review of Q value calculations for beta decay is provided.  The importance of spin and parity, and how it can be used to assess beta decay, is discussed. Modeling beta decay through the weak force is provided. The impact of Coulomb interactions on positron and electron spectral shape is presented.  The use of Kurie plots in understanding beta decay is introduced.  Selection rules in beta decay and beta transitions are explained. Calculating logft and its relation to spin and parity are presented. Double beta decay is discussed.

CHEM 418 Nuclear Chemistry, Winter 2016: Lecture 4 Alpha Decay

This lecture discusses alpha decay in radionuclides.  Theories on alpha decay are presented. Systematics and energetics involved in alpha decay are presented.  The correlation between Q value and decay energy is described.  The Geiger Nuttall relationship is provided, described, and utilized in a model for alpha decay. Tunneling is also exploited to described alpha decay, coupling energy and half-life.  Gamow calculations are shown to reflect the Geiger Nuttall relationship. Hindered alpha decay is discussed. Hindered alpha decay is employed to described nuclear properties. Hinderance factors are described, along with how they are calculated and where they can be found. Proton and other charged particle emission are presented. 

CHEM 418 Nuclear Chemistry, Winter 2016: Lecture 3 Decay Kinetics

This lecture covers the fundamental equations that describe the decay of radionuclides. Basic equations and their utility are presented.  Equations for mixtures, equilibrium, and branching of radionuclides are covered.  Examples are provided for error evaluation from counts, activity determination, evaluation of half life, and lifetime of isotopes. Discussion of natural radiation and dating are given. Examples are provided for dating from 238U, 14C, and the Oklo reactor. 

CHEM 418 Nuclear Chemistry, Winter 2016: Lecture 2 Nuclear Properties

A discussion on systematics of nuclear properties are presented.  Mass, mass excess, and mass distribution within the nucleus is presented.   Mass excess data are used to calculate energies in decays.  Equations for determining nuclear radii are provided.  Models that are used to describe the stability of nuclei are introduced.  Nuclear shapes and structures are introduced. PDF quiz 2 is due Wednesday 13 January.

CHEM 418 Nuclear Chemistry, Winter 2016: Lecture 1 Introduction and Chart of the Nuclildes

The class outcomes, expectations, and grading are explained.  A history of radioelement discovery and radiation research is presented. The Chart of the Nuclides and Table of the Isotopes are discussed and used.  Atomic properties, nuclear nomenclature, X-rays, types of decays and physical forces are introduced. The lecture is assigned on Monday 4 January and due Saturday 9 January. 

CHEM 418 Nuclear Chemistry, Winter 2016: Lecture 0 Online presentation methods

Using the online lecture format is presented. The lectures are available as notes without audio or animation, PowerPoint audio and animation, and MP4 video. The use of multiple formats should permit viewing of lectures on a host of platforms. The lecture is 3 minutes.