Determination of Trace Quantities of Thorium in Uranyl Nitrate by X-ray Emission Spectrometry


Book Description

Trace quantities of thorium in uranium were separated by precipitating thorium fluoride from a 1.0M HF-1.0M NH/sub 4/F matrix using yttrium as an internal standard and lanthanum as a carrier. The thorium precipitate was collected on a filter and analyzed by x-ray emission spectrometry. The method has a detection limit of about 15 mu g thorium per gram of uranium. The relative accuracy and precision at the 120- mu g thorium level was 95.5 plus or minus 1.5%. Studies on the rate of precipitation, sample size limitations, and the effect of varying molar fluoride-touranium ratios are discussed. The effects of potentially interfering anions, cations, and acids, which are commonly found in uranium system or form insoluble fluorides were studied. Radioactive tracer studies using /sup 234/Thh and /sup 88/Y were carried out at different levels of thorium and uranium to determine the absolute efficiency of the precipitation. The speed, selectivity, and precision of this x-ray method make it an excellent alternative to spectrophotometric methods. (auth).




Ion Beam Analysis


Book Description

Nuclear Instruments and Methods, Volume 168: Ion Beam Analysis presents the proceedings of the Fourth International Conference on Ion Beam Analysis, held in Aarhus, Denmark, on June 25–29, 1979. This book provides information pertinent to the methods and applications ion beam analysis. Organized into eight parts encompassing 95 chapters, this volume begins with an overview of the straggling of energy loss for protons and alpha particles. This text then examines the method for the calculation of the stopping of energetic ions in matter. Other chapters consider the method for measuring relative stopping powers for light energetic ions in highly reactive materials. This book discusses as well the stopping power and straggling of lithium ions with velocities around the Bohr velocity. The final chapter deals with the adsorption behavior of different gases on monocrystalline platinum surfaces. This book is a valuable resource for scientists, technologists, students, and research workers.



















Nuclear Medicine Radiation Dosimetry


Book Description

Complexities of the requirements for accurate radiation dosimetry evaluation in both diagnostic and therapeutic nuclear medicine (including PET) have grown over the past decade. This is due primarily to four factors: Growing consideration of accurate patient-specific treatment planning for radionuclide therapy as a means of improving the therapeutic benefit, development of more realistic anthropomorphic phantoms and their use in estimating radiation transport and dosimetry in patients, Design and use of advanced Monte Carlo algorithms in calculating the above-mentioned radiation transport and dosimetry which require the user to have a thorough understanding of the theoretical principles used in such algorithms, their appropriateness and their limitations, increasing regulatory scrutiny of the radiation dose burden borne by nuclear medicine patients in the clinic and in the development of new radiopharmaceuticals, thus requiring more accurate and robust dosimetry evaluations. An element common to all four factors is the need for precise radiation dosimetry in nuclear medicine, which is fundamental to the therapeutic success of a patient undergoing radionuclide therapy and to the safety of the patients undergoing diagnostic nuclear medicine and PET procedures. As the complexity of internal radiation dosimetry applied to diagnostic and therapeutic nuclear medicine increases, this book will provide the theoretical foundations for: enabling the practising nuclear medicine physicist to understand the dosimetry calculations being used and their limitations, allowing the research nuclear medicine physicist to critically examine the internal radiation dosimetry algorithms available and under development; and providing the developers of Monte Carlo codes for the transport of radiation resulting from internal radioactive sources with the only comprehensive and definitive.