Spring 2017 Chem 312 Lecture 19 Nuclear Forensics

This lecture covers the utilization of radionuclide properties to determine origin, age, used, and other properties of nuclear material. These isotope properties are defined as signatures of nuclear material, and include concentrations, relative amounts, and ratios. Specific details are provided on forensic signatures related to Pu and actinide isotopics. The signatures arising from reactors, separations, and post-detonation are included. For plutonium production these signatures include reactor power, reactor type, time of irradiation, separation method, and time since separation. The signatures include plutonium isotopic mass ratios, plutonium isotopic activity ratios, and transplutonium isotope ratios. Separation signatures include evaluation of Zr, Tc, Ru, and the lanthanides, with examples using Nd isotopics. Alloys of actinide metals as signatures are also presented. The lecture is 35 minutes.  The lecture is assigned 4 May 17 and due 9 May 17

Spring 2017 Chem 312 Lecture 18 Applications of Nuclear Material

The lecture provides examples of the use of radioactive isotopes. The methods used for isotope production are discussed. The difference between isotope production by accelerators and reactors is highlighted. Reactor isotope products are primarily neutron rich; while accelerator produced isotopes tend to be neutron poor. Isotopes used in the generation of neutrons are provided. These neutron generating sources are small with a relatively low neutron generating rate. They are used in element and compound identification. Examples of isotopes used as ionization sources are provided. The discussion focuses on the use of ²⁴¹Am for smoke detection and ⁶³Ni for explosives detection. The importance of ²³⁸Pu as a heat source is provided, with examples given for space exploration. A number of isotopes used in radiopharmaceuticals are introduced. Comparisons are given for diagnostic and therapeutic radiopharmaceuticals. The lecture is in 2 parts. Part 1 is 29 minutes, part 2 is 27 minutes. The lecture is assigned 2 May 17 and due 7 May 17.  

Spring 2017 CHEM 312 Exam 4

Assigned 27 Apr 2017
Due: 5 May 2017
2nd Due date: 8 May 2017
Lecture 14: Plutonium chemistry
Lecture 15: Americium and Curium chemistry Lecture 16: Chemistry in reactor fuel
Lecture 17: Separations
Lecture 18: Application of Nuclear Material
Lecture 19: Nuclear Forensics
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).

Office hours for exam 3 will be from 1000 to 1130 in the HRC 4th floor conference on Tuesday 2 May.

Spring 2017 Chem 312 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 1 is 40 minutes, part 2 is 40 minutes, part 3 is 24 minutes, and part 4 is 30 minutes.

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 and should be reviewed.

The lecture is assigned 20 April 17 and due 30 April 17.

Spring 2017 CHEM 312: Lecture 16 Nuclear Reactors and in-reactor chemistry

This lecture provides an overview of nuclear reactors and describes the chemistry of actinides and fission products in reactors. A broad overview of nuclear reactors is provided. The essential components of a reactor, fuel, cladding, coolant, and moderators, are described. Characteristics of reactor materials and nuclear fuels are given. A summary of reactor types, generally classified on coolant properties, is provided. The chemistry of nuclear fuel is provided, with an emphasis placed on understanding the 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 UO2are 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. The lecture is in two parts. Part 1 is length is 36 minutes, part 2 is 32 minutes.  The lecture is assigned 18-Apr-17 and due 23-Apr-17.

Spring 2017 CHEM 312: 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. The lecture is in 2 parts; part 1 is 29 minutes and part 2 is 26 minutes.  The lecture is assigned 4-Apr-17 and due 17-Apr-17.