The closure of Tank 16H will require removal of material from the annulus of the tank. Samples from Tank 16H annulus were characterized and tested to provide information to evaluate various alternatives for removing the annulus waste. The analysis found all four annulus samples to be composed mainly of Si, Na, and Al and lesser amounts of other elements. The XRD data indicate quartz (SiO{sub 2}) and sodium aluminum nitrate silicate hydrate (Na{sub 8}(Al{sub 6}Si{sub 6}O{sub 24})(NO{sub 3}){sub 2}.4H{sub 2}O) as the predominant crystalline mineral phases in the samples. The XRD data also indicate the presence of crystalline sodium nitrate, sodium nitrite, gibbsite, hydrated sodium bicarbonate, and muscovite. Based on the weight of solids remaining at the end of the test, the water leaching test results indicate approximately 20-35% of the solids dissolved after three contacts with an approximately 3:1 volume of water at 45 C. The chemical analysis of the leachates and the XRD results of the remaining solids indicate sodium salts of nitrate, nitrite, sulfate, and possibly carbonate/bicarbonate make up the majority of the dissolved material. The majority of these salts were dissolved in the first water contact and simply diluted with each subsequent water contact. The water …

During final preparations for start of the PDCF Inner Can (IC) qualification effort, welding was performed on an automated weld system known as the PICN. During the initial weld, using a pedigree canister and plug, a weld defect was observed. The defect resulted in a hole in the sidewall of the canister, and it was observed that the plug sidewall had not been consumed. This was a new type of failure not seen during development and production of legacy Bagless Transfer Cans (FB-Line/Hanford). Therefore, a team was assembled to determine the root cause and to determine if the process could be improved. After several brain storming sessions (MS and T, R and D Engineering, PDC Project), an evaluation matrix was established to direct this effort. The matrix identified numerous activities that could be taken and then prioritized those activities. This effort was limited by both time and resources (the number of canisters and plugs available for testing was limited). A discovery process was initiated to evaluate the Vendor's IC fabrication process relative to legacy processes. There were no significant findings, however, some information regarding forging/anneal processes could not be obtained. Evaluations were conducted to compare mechanical properties of the PDC …

Fermi has provided the largest sample of {gamma}-ray selected blazars to date. In this work we use a complete sample of FSRQs detected during the first year of operation to determine the luminosity function (LF) and its evolution with cosmic time. The number density of FSRQs grows dramatically up to redshift {approx}0.5-2.0 and declines thereafter. The redshift of the peak in the density is luminosity dependent, with more luminous sources peaking at earlier times; thus the LF of {gamma}-ray FSRQs follows a luminosity-dependent density evolution similarly to that of radio-quiet AGN. Also using data from the Swift Burst Alert Telescope we derive the average spectral energy distribution of FSRQs in the 10 keV-100GeV band and show that there is no correlation of the peak {gamma}-ray luminosity with {gamma}-ray peak frequency. The coupling of the SED and LF allows us to predict that the contribution of FSRQs to the Fermi isotropic {gamma}-ray background is 9.3{sub -1.0}{sup +1.6}% ({+-}3% systematic uncertainty) in the 0.1-100GeV band. Finally we determine the LF of unbeamed FSRQs, finding that FSRQs have an average Lorentz factor of {gamma} = 11.7{sub -2.2}{sup +3.3}, that most are seen within 5{sup o} of the jet axis, and that they represent …

Studies of nuclear resonance fluorescence based applications are presented. Important for these applications are data for isotopes such as {sup 239}Pu. Nuclear resonance fluorescence measurements of {sup 239}Pu were performed at the free electron laser facility at UC Santa Barbara using photons from a bremsstrahlung beam with an endpoint energies between 4.0 MeV and 5.5 MeV. Though no discrete states with significant confidence level were measured, we have excluded the region above 27(3) eV-barns, or 4-sigma, where we would expect only a small chance of false positives. Details of the measurements and the results are presented here.

Hg is a wide-spread contaminant in the environment and is toxic in all of its various forms. Data suggest that RHg+ and Hg2+ are toxic in two ways. At low levels, Hg species appear to disrupt membrane-bound respiration causing a burst of reactive oxygen species (ROS) that further damage the cell. At higher Hg concentrations, RHg+ and Hg2+ may form adducts with cysteine- and selenocysteine-containing proteins in all cellular compartments resulting in their inactivation. Although these mechansims for toxicity are generally accepted, the most sensitive targets associated with these mechanisms are not well understood. In this collaborative project involving three laboratories at three institutions, the overall goal was to develop of a mass spectrometry-based global proteomics methodology that could be used to identify Hg-adducted (and ideally, ROS-damaged) proteins in order to address these types of questions. The two objectives of this overall collaborative project were (1) to identify, quantify, and compare ROS- and Hg-damaged proteins in cells treated with various Hg species and concentrations to test this model for two mechanisms of Hg toxicity, and (2) to define the cellular roles of the ubiquitous bacterial mercury resistance (mer) locus with regards to how the proteins of this pathway interact to …

Proton radiography has become an important tool for predicting the performance of stockpiled nuclear weapons. Current proton radiography experiments at LANSCE are confined to relatively small targets on the order of centimeters in size because of the low beam energy. LANL scientists have made radiographs with 12 and 24 GeV protons produced by the accelerator at Brookhaven National Laboratory. These energies are in the range required for hydrotest radiography. The design of a facility for hydrotest radiography requires knowledge of the cross sections for producing high-energy particles in the forward direction, which are incorporated into the Monte Carlo simulation used in designing the beam and detectors. There are few existing measurements of neutron production cross sections for proton-nuclei interactions in the 50 GeV range, and almost no data exist for forward neutron production, especially for heavy target nuclei. Thus the data from the MIPP EMCAL and HCAL, for which our group was responsible, are critical to proton radiography. Since neutrons and photons cannot be focused by magnets, they cause a background “fog” on the images. This problem can be minimized by careful design of the focusing system and detectors. The purpose of our research was to measure forward production of …

This paper reviews the status of direct-drive inertial confinement fusion (ICF) research at the University of Rochester's Laboratory for Laser Energetics (LLE). LLE's goal is to demonstrate direct-drive ignition on the National Ignition Facility (NIF) by 2014. Baseline "all-DT" NIF direct-drive ignition target designs have been developed that have a predicted gain of 45 (1-D) at a NIF drive energy of ~1.6 MJ. Significantly higher gains are calculated for targets that include a DT-wicked foam ablator. This paper also reviews the results of both warm fuel and initial cryogenic-fuel spherical target implosion experiments carried out on the OMEGA UV laser. The results of these experiments and design calculations increase confidence that the NIF direct-drive ICF ignition goal will be achieved.

Synthetic DNA nanostructures are typically held together primarily by Holliday junctions. One of the most basic types of structures possible to assemble with only DNA and Holliday junctions is the triangle. To date, however, only equilateral triangles have been assembled in this manner - primarily because it is difficult to figure out what configurations of Holliday triangles have low strain. Early attempts at identifying such configurations relied upon calculations that followed the strained helical paths of DNA. Those methods, however, were computationally expensive, and failed to find many of the possible solutions. I have developed a new approach to identifying Holliday triangles that is computationally faster, and finds well over 95% of the possible solutions. The new approach is based on splitting the problem into two parts. The first part involves figuring out all the different ways that three featureless rods of the appropriate length and diameter can weave over and under one another to form a triangle. The second part of the computation entails seeing whether double helical DNA backbones can fit into the shape dictated by the rods in such a manner that the strands can cross over from one domain to the other at the appropriate spots. …

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This study presents detailed evaluation of the seasonal and episodic performance of the Community Multiscale Air Quality (CMAQ) modeling system applied to simulate air quality at a fine grid spacing (4 km horizontal resolution) in central California, where ozone air pollution problems are severe. A rich aerometric database collected during the summer 2000 Central California Ozone Study (CCOS) is used to prepare model inputs and to evaluate meteorological simulations and chemical outputs. We examine both temporal and spatial behaviors of ozone predictions. We highlight synoptically driven high-ozone events (exemplified by the four intensive operating periods (IOPs)) for evaluating both meteorological inputs and chemical outputs (ozone and its precursors) and compare them to the summer average. For most of the summer days, cross-domain normalized gross errors are less than 25% for modeled hourly ozone, and normalized biases are between {+-}15% for both hourly and peak (1 h and 8 h) ozone. The domain-wide aggregated metrics indicate similar performance between the IOPs and the whole summer with respect to predicted ozone and its precursors. Episode-to-episode differences in ozone predictions are more pronounced at a subregional level. The model performs consistently better in the San Joaquin Valley than other air basins, and episodic …

Todays solar cells are fabricated using metal oxide based transparent conductive coatings (TCC) or metal wires with optoelectronic performance exceeding that currently possible with Carbon Nanotube (CNT) based TCCs. The motivation for replacing current TCC is their inherent brittleness, high deposition cost, and high deposition temperatures; leading to reduced performance on thin substrates. With improved processing, application and characterization techniques Nanofiber and/or CNT based TCCs can overcome these shortcomings while offering the ability to be applied in atmospheric conditions using low cost coating processes At todays level of development, CNT based TCC are nearing commercial use in touch screens, some types of information displays (i.e. electronic paper), and certain military applications. However, the resistivity and transparency requirements for use in current commercial solar cells are more stringent than in many of these applications. Therefore, significant research on fundamental nanotube composition, dispersion and deposition are required to reach the required performance commanded by photovoltaic devices. The objective of this project was to research and develop transparent conductive coatings based on novel nanomaterial composite coatings, which comprise nanotubes, nanofibers, and other nanostructured materials along with binder materials. One objective was to show that these new nanomaterials perform at an electrical resistivity and …

Examination of proof test data for new (not previously installed) stainless steel (SS) trim spring operated pressure relief valves (SOPRV) reveals that adhesions form between the seat and disc in about 46% of all such SOPRV. The forces needed to overcome these adhesions can be sufficiently large to cause the SOPRV to fail its proof test (FPT) prior to installation. Furthermore, a significant percentage of SOPRV which are found to FPT are also found to ''fail to open'' (FTO) meaning they would not relief excess pressure in the event of an overpressure event. The cases where adhesions result in FTO or FPT appear to be confined to SOPRV with diameters < 1 in and set pressures < 150 psig and the FTO are estimated to occur in 0.31% to 2.00% of this subpopulation of SS trim SOPRV. The reliability and safety implications of these finding for end-users who do not perform pre-installation testing of SOPRV are discussed.

We introduce new concepts for increasing the efficiency of solid state lasers by using gratings deposited on laser slabs or disks. The gratings improve efficiency in two ways: (1) by coupling out of the slab deleterious amplified spontaneous emission (ASE) and (2) by increasing the absorption efficiency of pump light. The gratings also serve as antireflective coatings for the extracting laser beam. To evaluate the potential for such coatings to improve laser performance, we calculated optical properties of a 2500 groove/mm, tantala-silica grating on a 1cm x 4cm x 8cm titanium-doped sapphire slab and performed ray-trace calculations for ASE and pump light. Our calculations show substantial improvements in efficiency due to grating ASE-coupling properties. For example, the gratings reduce pump energy required to produce a 0.6/cm gain coefficient by 9%, 20% and 35% for pump pulse durations of 0.5 {micro}s, 1{micro}s and 3{micro}s, respectively. Gratings also increase 532-nm pump-light absorption efficiency, particularly when the product slab overall absorption is small. For example, when the single-pass absorption is 1 neper, absorption efficiency increases from 66%, without gratings, to 86%, when gratings are used.

Spent nuclear fuel from commercial reactors is comprised of 95-99 percent UO{sub 2} and 1-5 percent fission products and transuranic elements. Certain actinides and fission products are of particular interest in terms of fuel stability, which affects reprocessing and waste materials. The transuranics found in spent nuclear fuels are Np, Pu, Am, and Cm, some of which have long half- lives (e.g., 2.1 million years for {sup 237}Np). These actinides can be separated and recycled into new fuel matrices, thereby reducing the nuclear waste inventory. Oxides of these actinides are isostructural with UO{sub 2}, and are expected to form solid solutions. This project will use computational techniques to conduct a comprehensive study on thermodynamic properties of actinide-oxide solid solutions. The goals of this project are to: Determine the temperature-dependent mixing properties of actinide-oxide fuels; Validate computational methods by comparing results with experimental results; Expand research scope to complex (ternary and quaternary) mixed actinide oxide fuels. After deriving phase diagrams and the stability of solid solutions as a function of temperature and pressure, the project team will determine whether potential phase separations or ordered phases can actually occur by studying diffusion of cations and the kinetics of potential phase separations or …