Development of TRU waste mobile analysis methods for RCRA-regulated metals

This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). Glow-discharge mass spectrometry (GD-MS), laser-induced breakdown spectroscopy (LIBS), dc-arc atomic-emission spectroscopy (DC-ARC-AES), laser-ablation inductively-coupled-plasma mass spectrometry (LA-ICP-MS), and energy-dispersive x-ray fluorescence (EDXRF) were identified as potential solid-sample analytical techniques for mobile characterization of TRU waste. Each technology developers was provided with surrogate TRU waste samples in order to develop an analytical method. Following successful development of the analytical method, five performance evaluation samples were distributed to each of the researchers in a blind round-robin format. Results of the round robin were compared to known values and Transuranic Waste Characterization Program (TWCP) data quality objectives. Only two techniques, DC-ARC-AES and EDXRF, were able to complete the entire project. Methods development for GD-MS and LA-ICP-MS was halted due to the stand-down at the CMR facility. Results of the round-robin analysis are given for the EDXRF and DCARC-AES techniques. While DC-ARC-AES met several of the data quality objectives, the performance of the EDXRF technique by far surpassed the DC-ARC-AES technique. EDXRF is a simple, rugged, field portable instrument that appears to hold great promise for mobile characterization of TRU waste. The performance of this technique needs to be tested on real TRU samples in order to assess interferences from actinide constituents. In addition, mercury and beryllium analysis will require another analytical technique because the EDXRF method failed to meet the TWCP data quality objectives. Mercury analysis is easily accomplished on solid samples by cold vapor atomic fluorescence (CVAFS). Beryllium can be analyzed by any of a variety of emission techniques

The Debye-Waller Factor in solid 3He and 4He

The Debye-Waller factor and the mean-squared displacement from lattice sites for solid 3He and 4He were calculated with Path Integral Monte Carlo at temperatures between 5 K and 35 K, and densities between 38 nm^(-3) and 67 nm^(-3). It was found that the mean-squared displacement exhibits finite-size scaling consistent with a crossover between the quantum and classical limits of N^(-2/3) and N^(-1/3), respectively. The temperature dependence appears to be T^3, different than expected from harmonic theory. An anisotropic k^4 term was also observed in the Debye-Waller factor, indicating the presence of non-Gaussian corrections to the density distribution around lattice sites. Our results, extrapolated to the thermodynamic limit, agree well with recent values from scattering experiments.Comment: 5 figure

Electron-electron interactions and two-dimensional - two-dimensional tunneling

We derive and evaluate expressions for the dc tunneling conductance between interacting two-dimensional electron systems at non-zero temperature. The possibility of using the dependence of the tunneling conductance on voltage and temperature to determine the temperature-dependent electron-electron scattering rate at the Fermi energy is discussed. The finite electronic lifetime produced by electron-electron interactions is calculated as a function of temperature for quasiparticles near the Fermi circle. Vertex corrections to the random phase approximation substantially increase the electronic scattering rate. Our results are in an excellent quantitative agreement with experiment.Comment: Revtex style, 21 pages and 8 postscript figures in a separate file; Phys. Rev. B (in press

Geological Map of the Antelope Peak NE 7.5’ Quadrangle and the southern 2/3rd of the Maricopa 7.5’ Quadrangle, Pinal County, Arizona, v 2.0

This report and accompanying maps describe the geology, geomorphology, and geologic hazards of the Maricopa area in western Pinal County, central Arizona. This mapping covers all of the Antelope Peak NE 7 ½’ quadrangle and most of the Maricopa 7 ½’, and includes the community of Maricopa (Figure 1). The map area encompasses part of the basin floor occupied by Santa Rosa Wash and the Santa Cruz River, the gently sloping piedmonts flanking the west side of the basin floor, and a few bedrock hills (inselbergs) outboard from the Haley Hills, Palo Verde Mountains and Table Top Mountains to the west and southwest of the map area. Agricultural activity and more recently urban development have substantially modified the surface of the basin floor and most of the piedmont areas. Maricopa is developing into a significant population center and rapid development is occurring on the basin floor and the piedmont in the northern part of the map area. The map area includes part of the Maricopa- Stanfield sedimentary basin, from which tremendous amounts of ground water have been extracted primarily for agricultural purposesDocuments in the AZGS Document Repository collection are made available by the Arizona Geological Survey (AZGS) and the University Libraries at the University of Arizona. For more information about items in this collection, please contact [email protected]

Fontes de lactose, níveis de lisina dietéticos e peso dos leitões ao desmame Lactose sources and lysine levels in diets for weaning piglets

Desenvolveu-se um experimento com o objetivo de avaliar o uso de fontes de lactose (soro de leite em pó e lactose) e níveis de lisina em rações (1,20 e 1,50%), além do peso ao desmame (<6,0 e >6,0 kg), sobre o desempenho e a morfologia intestinal de 384 leitões desmamados com diferentes pesos e idade de 21 dias. Os leitões foram distribuídos em delineamento inteiramente casualizado em esquema fatorial 2 x 2 x 2, totalizando oito tratamentos em quatro repetições cada. Três leitões de cada tratamento foram abatidos aos 42 dias de idade, quando foram coletadas amostras do duodeno para estudo da morfologia intestinal. Foram avaliadas as características de desempenho ganho de peso, consumo de ração e conversão alimentar. Altura das vilosidades, profundidade de criptas duodenais e a relação altura de vilosidades/profundidade de criptas, bem como a relação peso do pâncreas/peso da carcaça, foram as características morfológicas avaliadas. O uso de lactose em rações à base de milho e farelo de soja proporcionou melhor desempenho dos leitões quando combinado a um nível de 1,5% de lisina. Concluiu-se ainda que os tipos de dietas estudados não exerceram efeito sobre a morfologia do duodeno e a relação peso do pâncreas/peso corporal e que a altura das vilosidades é uma função direta do peso do leitão.<br>One experiment was carried out to evaluate the use of lactose sources (dried whey and lactose) and lysine levels (1.20 and 1.50%) in diets for weaned piglets with diferent body weight at 21 days of age, regarding performance and intestinal morphology of piglets in initial phase. Three hundred and eighty-four piglets from 21 to 42 days were sorted in a complete randomized design with a 2 x 2 x 2 factorial arrangement, in a total of eight treatments and four replications each. Samples of duodenum from three piglets slaughtered at 42 days of age were harvested from each treatment to study intestinal morphology. The following performance characteristics were evaluated: weight gain, feed intake and feed conversion. The morphologycal parameters were as follows: villous height, duodenum crypt depth, villous height/duodenum crypt depth ratio and pancreas/carcass weight ratio. Performance of piglets fed corn-soybean meal- based diets with lactose was better when the level of lysine was of 1.5%. It was also concluded that the type of diets studied did not alter the morphologycal parameters and that the villous height is a direct function of piglet weight