[en] A new fecal analysis method that dissolves plutonium oxide was developed at the Westinghouse Savannah River Site. Diphonix Resin (Eichrom Industries), is used to pre-concentrate the actinides from digested fecal samples. A rapid microwave digestion technique is used to remove the actinides from the Diphonix Resin, which effectively extracts plutonium and americium from acidic solutions containing hydrofluoric acid. After resin digestion, the plutonium and americium are recovered in a small volume of nitric acid that is loaded onto small extraction chromatography columns, TEVA Resin and TRU Resin (Eichrom Industries). The method enables complete dissolution of plutonium oxide and provides high recovery of plutonium and americium with good removal of thorium isotopes such as thorium-228

[en] The second Maxi-Marathon for the defense of the environment organized by the World Council of Nuclear Workers will take place on May 9 and 10, 1997 between Paris and Brussels. this second running, the runners will hand over to Jacques Santer, President of the European Commission, a manifesto reminding the European Union of the advantages of nuclear energy

[en] Nuclear power plants with outstanding operating records and cost-conscious management can continue to compete with other forms of generation as the electricity business becomes more competitive. Natural gas-fired units will set the pricing standard with which nuclear power plants must compete

[en] Separation of U, Th, and Pa from environmental samples (shells, minerals, etc.) is often required by geochemists for geochronological and other applications. The authors describe here an efficient and relatively rapid method for separation of these elements from marine phosphate minerals and sediments. The main separation is accomplished via an extraction chromatographic column with a final cleanup using standard ion-exchange resin. There is thus no need to employ waste-generating solvent extractions which are commonly used for Pa separations. Because of the low natural abundance of ²³¹Pa, the authors conducted several tests to optimize its recovery. The authors also took steps to ensure minimum contamination of the Pa source by U or Th nuclides which could cause significant spectral interferences. Samples analyzed using this method show typical Pa yields of about 90% and U/Th contamination of less than 0.02% if the combined U/Th activity

[en] Although many techniques are available for determination of the actinide elements, alpha-particle spectrometry remains a popular choice within the radioanalytical community because of its performance, availability, and familiarity. Outside radioanalytical circles, inductively coupled plasma-mass spectrometry (ICP-MS) is being applied with increasing frequency to many of the same measurements because of its isotopic selectivity, speed, and sensitivity. At Argonne National Laboratory, the authors are exploiting the strengths of both techniques as they develop new radioanalytical procedures in support of environmental restoration at U.S. Department of Energy (DOE) facilities. In this presentation, the authors will describe a new preparative strategy which allows an analyst to flexibly choose either measurement technique, and they will compare the performance of both techniques as they are applied to the determination of actinide isotopes in soils and smears. This comparison suggests that alpha-particle spectrometry and ICP-MS can be used interchangeably in many applications. On that basis, the authors are continuing to refine analytical procedures with the goal of widespread implementation in the near future

[en] Recent technical advances and unique approaches to calibration now allow for improved calibration of in vivo measurement systems. The new approach utilizes Monte Carlo calculational techniques along with a library of Magnetic Resonance images consisting of 32 human or human-like phantoms. The library of whole body images is the largest of its kind currently available and a prime resource for expanded DOE efforts in worker health and safety. This technique will save user facilities time and funds in the calibration of in vivo measurement systems while at the same time allowing greater flexibility in the selection of calibrations appropriate for a subject's physical stature

[en] The principles of the Monitorad reg-sign system for the real-time monitoring and recording of electron processor performance are reviewed. The device employs multiple solid-state radiation detectors positioned to view a portion of the bremsstrahlung generated by the electron beam at the window support plane. This corrected signal provides a measure of the current density, hence dose rate, at each position. Software has been developed for analysis and display of these signals so that real time, simultaneous determinations of beam uniformity, dose rate, delivered dose and electron-beam energy are possible. The performance of the system when used in parallel with NIST-traceable Far West Technology film dosimetry on a small sterilizer will be discussed. Configurations for larger production machines will be described

[en] Extended-range or n-type germanium detectors that allow the gamma-ray spectroscopist to detect X and gamma radiation from about 5 keV to the MeV range in a single measurement are becoming more popular. Several articles in this department have pointed out the importance of X-ray/gamma-ray coincidence effects in calibrations and routine measurements using these types of detectors. This article discusses another type of coincidence effect that can be important in extended-range detectors, beta-gamma coincidence. This discussion includes a measurement of the effect for a filter-paper geometry

[en] A non-intrusive inspection technique that probes samples with neutrons can analyze the content of coal and cement and detect explosives and drugs. It also shows promise for locating plastic and wooden land mines. Developed by The Department of Energy's Oak Ridge National Laboratory (ORNL) and Western Kentucky University (WKU) researchers, the pulsed fast-thermal neutron analysis system bombards a sample with pulses of fast and slow, or thermal neutrons. Fast neutrons collide with some atoms, triggering the release of gamma rays. Between pulses, thermal neutrons are captured by other atoms, causing emission of gamma rays. Detectors measure energies of the combined gamma rays, which are unique for each element

[en] Large-scale dosimetry applications require cost-effective, easy to manufacture dosimeters that are available in high volume with good precision and uniformity between batches. The ability to re-analyze a dosimeter along with the ability to perform necessary exposure diagnostics familiar to film dosimetrists are also desirable qualities of a dosimetric system. Battelle has developed photostimulable phosphor techniques that allow all these features to be combined into one practical dosimetry system. Three storage phosphor techniques developed by Battelle will be reviewed