In support of X-band photoinjector development efforts at LLNL, a 50 MW test station is being constructed to investigate structure and photocathode optimization for future upgrades. A SLAC XL-4 klystron capable of generating 50 MW, 1.5 microsecond pulses will be the high power RF source for the system. Timing of the laser pulse on the photocathode with the applied RF field places very stringent requirements on phase jitter and drift. To achieve these requirements, the klystron will be powered by a state of the art, solid-state, high voltage modulator. The 50 MW will be divided between the photoinjector and a traveling wave accelerator section. A high power phase shifter is located between the photoinjector and accelerator section to adjust the phasing of the electron bunches with respect to the accelerating field. A variable attenuator is included on the input of the photoinjector. The distribution system including the various x-band components is being designed and constructed. In this paper, we will present the design, layout, and status of the RF system.

For this paper, we evaluated the impact of repetitive cleans on a photomask that was fabricated and patterned for extreme ultraviolet lithography exposure. The lithographic performance of the cleaned mask, in terms of process window and line edge roughness, was monitored with the SEMATECH Berkeley micro-exposure tool (MET). Each process measurement of the cleaned mask was compared to a reference mask with the same mask architecture. Both masks were imaged on the same day in order to eliminate any process-related measurement uncertainties. The cleaned mask was periodically monitored with atomic force microscopy (AFM) measurements and pattern widths were monitored using scanning electron microscopy (SEM). In addition, reflectivity changes were also tracked with the aid of witness plate measurements. At the conclusion of this study, the mask under evaluation was cleaned 22 times; with none of the evaluation techniques showing any significant degradation in performance.

Magnetic Resonance Imaging (MRI) techniques have been used to detect areas of low crosslink density in damaged silicone parts in an effort to develop a QA/QC protocol to be used in the development of new parts. Model materials of varying crosslink density first demonstrated the applicability of the method. Analysis of damaged pads has been shown to be clearly distinguishable by MRI. It is our belief that both the T{sub 2} weighted SPI NMR and the T{sub 2} weighted water/fat suppression MRI experiments can be used to map out the location of different cross-linking densities, ultimately determining the quality or homogeneity in polymers.

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The activity reported in this presentation is to provide the mechanical and physical property information needed to allow rational design, development and/or choice of alloys, manufacturing approaches, and environmental exposure and component life models to enable oxy-fuel combustion boilers to operate at Ultra-Supercritical (up to 650{degrees}C & between 22-30 MPa) and/or Advanced Ultra-Supercritical conditions (760{degrees}C & 35 MPa).

We present a simple analytical solution for one dimensional steady heat transfer with convection and conduction through a multi-layer system such as a vadose zone. We assume that each layer is homogeneous and has a constant thermal diffusivity. The mass/heat flow direction is perpendicular to the layers, and the mass flow rate is a constant. The analytical solution presented in this study also assumes constant known temperatures at the two boundaries of the system. Although the analytical solution gives the temperature as a function of a few parameters, we focus on the inverse application to estimate the percolation rate to high degree of accuracy (e.g., to mm/y). In some other cases the solution may also be helpful in characterizing potential lateral flow along layer divides.

The application of forensic science techniques to electrical equipment failure investigation has not been widely documented in the engineering world. This paper is intended to share an example of using material characterization techniques to support an initial cause determination of an electrical component failure event. The resulting conclusion supported the initial cause determination and ruled out the possibility of design deficiencies. Thus, the qualification testing of the equipment was allowed to continue to successful completion.

The interrogation of molecular vibrations in crystalline and amorphous solids by Raman and infrared spectroscopy methods can provide a wealth of revealing information concerning the composition, morphology, and spatial distribution of the extant phases. When these measurements are made in situ, such as during processes taking place in extreme environments (e.g., elevated temperature and pressure, oxidizing or reducing), where phases are evolving and/or dissipating, it is also possible to derive kinetic and mechanistic parameters. This paper summarizes the possibilities and limitations involved in using various types of Raman and infrared measurement methods to study metal dusting corrosion. Applications of conventional, microprobe, and imaging molecular spectroscopy approaches are discussed, with examples taken directly from metal dusting investigations. Some perspective is offered concerning the origin of observable condensed matter phonons emanating from the surface films and the carbon particles that accompany carbon dusting on various types of metals and alloys. Concepts for the systematic investigation of carbon dusting chemistry using molecular spectroscopy methods are presented.

This paper describes the use of a ''mesh potential'' function for automatic coarsening of meshes in discrete ordinates neutral particle transport codes. For many transport calculations, a user may find it helpful to have the code determine a ''good'' neutronics mesh. The complexity of a problem involving millions of mesh cells, dozens of materials, and many energy groups makes it difficult to determine an adequate level of mesh refinement with a minimum number of cells. A method has been implemented in PARTISN (Parallel Time-dependent SN) to calculate a ''mesh potential'' in each original cell of a problem, and use this information to determine the maximum coarseness allowed in the mesh while maintaining accuracy in the solution. Results are presented for a simple x-y-z fuel/control/reflector problem.

The need for proper consideration of energy-related performance aspects during building design has been identified since the energy crises of the 1970s. However, energy performance is still considered in a very small fraction of building projects, mainly because proper consideration is very expensive. It requires the use of computational software tools, which are not easy to learn and are time-consuming to use. Several attempts have been made to facilitate the use of energy simulation tools, but none has brought a significant increase in the consideration of energy performance. Energy related performance criteria are still considered only in a small fraction of buildings and, in most cases, after most of the building design is complete. This paper is focused on the main barriers in properly considering energy-related performance aspects in building decisions, which range from sociopolitical, to technical. The paper includes consideration of issues related to the general interest of the building industry in energy performance and environmental impact, current practice trends, modeling capabilities and performance of tools, compatibility of computational models and availability of data. Finally, a strategy for government-industry collaboration towards removing the barriers is presented, along with the main issues that need to be resolved towards potential implementation.

Our study reveals that supplying gasoline-equivalent demand for the low-market-share scenario requires a capital investment of less than $40 billion for all fuels except H{sub 2}, which will require a total cumulative investment of $150 billion. By contrast, cumulative capital investments under the high-market-share scenario are $50 billion for LNG, $90 billion for ethanol, $100 billion for methanol, $160 billion for CNG and DME, and $560 billion for H{sub 2}. Although these substantial capital requirements are spread over many years, their magnitude could pose a challenge to the widespread introduction of 3X vehicles. Fossil fuel use by US light-duty vehicles declines significantly with introduction of 3X vehicles because of fuel-efficiency improvements for 3X vehicles and because of fuel substitution (which applies to the nonpetroleum-fueled alternatives). Petroleum use for light-duty vehicles in 2030 is reduced by as much as 45% relative to the reference scenario. GHG emissions follow a similar pattern. Total GHG emissions decline by 25-30% with most of the propulsion system/fuel alternatives. For those using renewable fuels (i.e., ethanol and H{sub 2} from solar energy), GHG emissions drop by 33% (H{sub 2}) and 45% (ethanol). Among urban air pollutants, urban NOX emissions decline slightly for 3X vehicles using CIDI …

The responses of the anaerobic, sulfate-reducing Desulfovibrio vulgaris Hildenborough to low oxygen exposure (0.1% O{sub 2}) were monitored via transcriptomics and proteomics. Exposure to 0.1% O{sub 2} caused a decrease in growth rate without affecting viability. A concerted up regulation in the predicted peroxide stress response regulon (PerR) genes was observed in response to the 0.1% O{sub 2} exposure. Several of these candidates also showed increases in protein abundance. Among the remaining small number of transcript changes was the up regulation of the predicted transmembrane tetraheme cytochrome c3 complex. Other known oxidative stress response candidates remained unchanged during this low O{sub 2} exposure. To fully understand the results of the 0.1% O{sub 2} exposure, transcriptomics and proteomics data were collected for exposure to air using a similar experimental protocol. In contrast to the 0.1% O{sub 2} exposure, air exposure was detrimental to both the growth rate and viability and caused dramatic changes at both the transcriptome and proteome levels. Interestingly, the transcripts of the predicted PerR regulon genes were down regulated during air exposure. Our results highlight the differences in the cell wide response to low and high O{sub 2} levels of in D. vulgaris and suggest that while exposure …

The authors present results of a study of 12 dust-reddened quasars with 0.4 < z < 2.65 and reddenings in the range 0.15 < E(B-V) < 1.7. They obtained ACIS-S X-ray spectra of these quasars, estimated the column densities towards them, and hence obtained the gas:dust ratios in the material obscuring the quasar. They detect all but one of the red quasars in the X-rays. Even though there is no obvious correlation between the X-ray determined column densities of the sources and their optical color or reddening, all of the sources show absorbed X-ray spectra. When they correct the luminosity for absorption, they can be placed among luminous quasars; therefore their objects belong to the group of high luminosity analogues of the sources contributing to the X-ray background seen in deep X-ray observations. Such sources are also found in serendipitous shallow X-ray surveys. There is a hint that the mean spectral slope of the red quasar is higher than that of normal, unobscured quasars, which could be an indication for higher accretion rates and/or an evolutionary effect. They investigate the number density of these sources compared to type 2 AGN based on the X-ray background and estimate how many moderate …

The Steam Generator Few Tube Test (FTT) was part of an extensive testing program carried out in support of the Clinch River Breeder Reactor Plant (CRBRP) steam generator design. The testing of full-length seven-tube evaporator and three-tube superheater models of the CRBRP design was conducted to provide steady-state thermal/hydraulic performance data to full power per tube and to verify the absence of multi-year endurance problems. This paper describes the problems encountered with the mechanical features of the FTT model design which led to premature test termination, and the results of the post-test examination. Conditions of tube bowing and significant tube and tube support gouging was observed. An interpretation of the visual and metallurgical observations is also presented. The CRBRP steam generator has undergone design evaluations to resolve observed deficiences found in the FFTM.

While oil shale has the potential to provide a substantial fraction of our nation's liquid fuels for many decades, cost and environmental acceptability are significant issues to be addressed. Lawrence Livermore National Laboratory (LLNL) examined a variety of oil shale processes between the mid 1960s and the mid 1990s, starting with retorting of rubble chimneys created from nuclear explosions [1] and ending with in-situ retorting of deep, large volumes of oil shale [2]. In between, it examined modified-in-situ combustion retorting of rubble blocks created by conventional mining and blasting [3,4], in-situ retorting by radio-frequency energy [5], aboveground combustion retorting [6], and aboveground processing by hot-solids recycle (HRS) [7,8]. This paper reviews various types of processes in both generic and specific forms and outlines some of the tradeoffs for large-scale development activities. Particular attention is given to hot-recycled-solids processes that maximize yield and minimize oil shale residence time during processing and true in-situ processes that generate oil over several years that is more similar to natural petroleum.

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Paper describes studying aiming to evaluate changes in pilot aircraft-assisted suicide risks, i.e., a copycat effect, in the U.S. and Germany after the Germanwings 2015 incident in the French Alps.

Imagery from coresident sensor platforms, such as unmanned aerial vehicles, can be combined using, multiresolution decomposition of the sensor images by means of the two-dimensional wavelet transform. The wavelet approach uses the combination of spatial/spectral information at multiple scales to create a fused image. This can be done in both an ad hoc or model-based approach. We compare results from commercial ``fusion`` software and the ad hoc, wavelet approach. Results show the wavelet approach outperforms the commercial algorithms and also supports efficient compression of the fused image.

Among Dirac's many contributions to modern physics is the idea that charge quantization is natural in a theory with magnetic monopoles. The existence of magnetic monopoles would have drastic effects on the evolution of the universe, on galactic magnetic fields, and perhaps on the x-ray luminosity of neutron stars. Some astrophysical implications of massive magnetic monopoles are reviewed here.

We report deflagration rate measurements on PBXN-109 (RDWAVHTPB) and Composition B (RXDTTNThrvax) at pressures from 1,500-100,000 psi (10-700 MPa). This was done with the LLNL High Pressure Strand Burner, in which embedded wires are used to record the time-of-arrival of the burn front in the cylindrical sample as a function of pressure. The propellant samples are 6.4 mm in diameter and 6.4 mm long, with burn wires inserted between samples. Burning on the cylindrical surface is inhibited with an epoxy or polyurethane layer. With this direct measurement we do not have to account for product gas equation of state or heat losses in the system, and the burn wires allow detection of irregular burning. We report deflagration results for PBXN-109 as received, and also after it has been damaged by heating. The burn behavior of pristine PBXN-109 is very regular, and exhibits a reduction in pressure exponent from 1.32 to 0.85 at pressures above 20,000 psi (135 MPa). When PBXN-109 is thermally damaged by heating to 170-180 C, the deflagration rate is increased by more than a factor of 10. This appears to be a physical effect, as the faster burning may be explained by an increase in surface area. …

Alloy 22 (N06022) is a nickel-based alloy highly resistant to corrosion. In some aggressive conditions of high chloride concentration, temperature and applied potential, Alloy 22 may suffer crevice corrosion, a form of localized corrosion. There are several electrochemical methods that can be used to determine localized corrosion in metallic alloys. One of the most popular for rapid screening is the cyclic potentiodynamic polarization (CPP). This work compares the results obtained by measuring the localized corrosion resistance of Alloy 22 using both CPP and the more cumbersome Tsujikawa-Hisamatsu Electrochemical (THE) method. The electrolytes used were 1 M NaCl and 5 M CaCl{sub 2}, both at 90 C. Results show that similar repassivation potentials were obtained for Alloy 22 using both methods. That is, in cases where localized corrosion is observed using the fast CPP method, there is no need to use THE method since it takes ten times longer to obtain comparable results in spite that the mode of corrosion attack that results in the tested specimens are different.

This study assessed chemical treatment options for decomposing the tetraphenylborate in High Level Waste (HLW) Tank 48H. Tank 48H, located at the Savannah River Site in Aiken, SC, contains approximately one million liters of HLW. The tetraphenylborate slurry represents legacy material from commissioning of an In Tank Precipitation process to separate radioactive cesium and actinides from the nonradioactive chemicals. During early operations, the process encountered an unplanned chemical reaction that catalytically decomposed the excess tetraphenylborate producing benzene. Subsequent research indicated that personnel could not control the operations within the existing equipment to both meet the desired treatment rate for the waste and maintain the benzene concentration within allowable concentrations. Since then, the Department of Energy selected an alternate treatment process for handling high-level waste at the site. However, the site must destroy the tetraphenylborate before returning the tank to HLW service. The research focuses on identifying treatments to decompose tetraphenylborate to the maximum extent feasible, with a preference for decomposition methods that produce carbon dioxide rather than benzene. A number of experiments examined whether the use of oxidants, catalysts or acids proved effective in decomposing the tetraphenylborate. Additional experiments developed an understanding of the solid, liquid and gas decomposition products.

Density Functional Theory (DFT) is used to investigate the action of hydrogen getter 1,4-diphenyl-butadiyne, or DPB, on Pd(110) surface. We study reaction pathways and energetics of several relevant processes, including H{sub 2} adsorption, dissociation and migration on the metal surface, getter-metal interaction, and the energetics of H uptake by the getter. We also explore the effect of impurities like CO and CO{sub 2} on the action of the getter. Activation barriers for certain reactions are computed to shed light on the feasibility of such processes at room temperature.