Remediation of potentially acidified Hanford wastes using tri-n-octyl phosphine oxide extraction chromatographic materials

As the Hanford site undergoes remediation, significant economies could be realized if aluminum and chromium are kept from High Level Waste glass produced at the Hanford Waste Treatment Plant (WTP). An acidic scrub of the Hanford sludge could enhance Al removal, although such treatment could lead to the mobilization of transuranic elements. If mobilization were minor, a chromatographic secondary cleanup of the acidic waste stream may be preferred to allow preconcentration of radionuclides prior to processing through the Hanford WTP. This study examines tri-n-octyl phosphine oxide coated resins as a chromatographic means for the removal of transuranics from a secondary waste stream. Metal uptake kinetics and mechanisms for transuranics and a simulant transuranic (europium) with the developed resin are characterized in both batch and column operation modes. Results indicate up to 99% of the radioactive material present from an acidic sludge leach may be recovered using extraction chromatography providing an effective avenue for high aluminum content tank pre-treatment

The First VERITAS Telescope

The first atmospheric Cherenkov telescope of VERITAS (the Very Energetic Radiation Imaging Telescope Array System) has been in operation since February 2005. We present here a technical description of the instrument and a summary of its performance. The calibration methods are described, along with the results of Monte Carlo simulations of the telescope and comparisons between real and simulated data. The analysis of TeV $\gamma$-ray observations of the Crab Nebula, including the reconstructed energy spectrum, is shown to give results consistent with earlier measurements. The telescope is operating as expected and has met or exceeded all design specifications.Comment: Accepted by Astroparticle Physic

REE behavior and sorption on weak acid resins from buffered media

Rare Earth Elements (REEs) are of great importance to modern day societies. Although abundant, concentration of REE minerals in ores are generally quite low, with high concentration of impurities. To counteract this, selective extraction processes must be undertaken. Selective adsorption of REE from buffered media solutions on Purolite S910 and Amberlite IRC86 weak acid resins has been studied. Batch experiments have been carried out on solutions containing a selection of REEs, Y3+, Fe3+ and Al3+ in unbuffered media, malic acid, formic acid, acetic acid, alanine and lactic acid to determine the best extracting media. Isotherm behavior and extraction kinetics of IRC86 were determined for acetic acid media, at the most effective pH that was determined to be 4.38. The isotherms were conducted for La3+, Sm3+, Er3+ and Y3+ determining extraction maxima of 0.29, 0.34, 0.49 and 0.60 mmol L−1, respectively, with adsorption energies increasing with the same trend. Kinetic experiments determined that mid REEs were the fastest adsorption, with light REEs and heavy REEs displaying similar half-lives and Y3+ measuring the smallest half-life out of the studied ions

Partitioning of U, Np, Th, and Eu between acidic aqueous Al(NO3)​3 solutions and various TOPO extraction chromatographic materials

As the Hanford site undergoes remediation, it is noted that significant economies could be realized by minimizing the amt. of aluminum deposited in High-​Level Waste glass. Though such a step is not planned, an acidic scrub of the Hanford sludge could enhance Al removal. It is likely that the resulting Al(NO3)​3 Al(NO3)​3 soln. would contain measurable amts. of transuranic elements, thus the thus the soln. might require some secondary treatment to remove TRU contamination. Thus far, extn. chromatog. (EXC) has shown promise [1] as an alternative to a liq.-​liq. remediation of the Hanford site. Previous EXC studies have shown >99​% of the Eu can be extd. from simulated Al​/Cr waste. This study continues an examn. of a hypothetical secondary cleanup of the waste by studying the removal of UO22+, NpO2+, NpO22+ and Th4+ from using tri-​n-​octyl phospine oxide (TOPO) impregnated XAD7 resins. Neptunium was held in the V and VI oxidn. states using ascorbic acid and chromate, resp. Initial results show extn. following classical metal recovery trends, wherein an increased Zeff correlates with increased distribution of the metal into the org. resin phase. The uptake of Eu3+ (representative of An3+) on a column of the same material was also investigated. Uptake kinetics were improved by wetting the TOPO-​XAD7 resin with n-​dodecane (TOPO-​XAD7n)​. The presence of n-​dodecane also provided consistency between batch mode and column mode metal recovery. Preliminary data show >99​% recovery of metal ions with a Zeff ≥ 3 under various simulated conditions

Isotopic profiling of diet, health, and mobility amongst the non-adult Gepid population buried at the Archuid Cemetery in Transylvania, Romania (4th –7th centuries AD)

The Gepids were a migratory, barbarian population that inhabited the Carpathian Mountain basin from the 3 rd to the 7 th century (AD) in what is now Transylvania, Romania. The Gepids were subsumed into the histories of other clans, leaving very little reliable information about how this population lived and died. It is hypothesized that the continued migration/emigration would affect the Gepid’s ability to access adequate nutrition, resulting in skeletal evidence of nutritional stress and/or metabolic. The Archuid cemetery (Transylvania, Romania), was occupied by the Gepids from the 4 th -7 th centuries AD, was excavated by Romanian archaeologists (1979-1982), unearthing 30 individuals

Keeping up with the kids: mobility patterns of young individuals from the St. Mary Magdalen Leprosy Hospital (Winchester)

Leprosy is one of the few specific infectious diseases that can be studied in bioarchaeology due to its characteristic debilitating and disfiguring skeletal changes. Leprosy has been, and continues to be, one of the most socially stigmatising diseases in history, over-riding all other aspects of social identity for the sufferers and frequently resulting in social exclusion. This study examines the stable isotopic evidence of mobility patterns of children, adolescents, and young adult individuals with the lepromatous form of leprosy in Medieval England (10th –12 th centuries AD) to assess whether the individuals buried with the disease were non-locals, possibly from further afield. Enamel samples from 19 individuals from the St. Mary Magdalen Leprosy Hospital, Winchester (UK) were selected for strontium (87Sr/86Sr) and oxygen (d18O) radiogenic and stable isotope analysis based on age at death (<30 years), the presence of bone changes associated with lepromatous leprosy, and the underlying geology of their burial locations. The results from these data indicate that the St. Mary Magdalen Leprosy Hospital received an almost equal mixture of local and non-local individuals from further afield, including early pilgrims. At present, the St. Mary Magdalen Leprosy Hospital is the earliest dedicated leprosaria found within Britain and mobility studies such as these can help elucidate and test some of the broader historical notions and identities associated with the movements of those infected with the disease in Medieval England