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Reduced Dimensionality Lithium Niobate Microsystems

Eichenfield, Matt

The following report describes work performed under the LDRD program at Sandia National Laboratories October 2014 and September 2016. The work presented demonstrates the ability of Sandia Labs to develop state-of-the-art photonic devices based on thin film lithium niobate (LiNbO3 ). Section 1 provides an introduction to integrated LiNbO3 devices and motivation for developing thin film nonlinear optical systems. Section 2 describes the design, fabrication, and photonic performance of thin film optical microdisks fabricated from bulk LiNbO3 using a bulk implantation method developed at Sandia. Sections 3 and 4 describe the development of similar thin film LiNbO3 structures fabricated from LiNbO3 on insulator (LNOI) substrates and our demonstration of optical frequency conversion with state-of-the-art efficiency. Finally, Section 5 describes similar microdisk resonators fabricated from LNOI wafers with a buried metal layer, in which we demonstrate electro-optic modulation.

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An Atomistic Introduction to Orientation Relations Between Phases in the Face-centered Cubic to Body-centered Cubic Phase Transition in Iron and Steel

Wills, Ann E.; Thompson, A.P.; Raman, Sumathy

We establish an atomistic view of the high- and low-temperature phases of iron/steel as well as some elements of the phase transition between these phases on cooling. In particular we examine the 4 most common orientation relationships between the high temperature austenite and low-temperature ferrite phases seen in experiment. With a thorough understanding of these relationships we are prepared to set up various atomistic simulations, using techniques such as Density Functional Theory and Molecular Dynamics, to further study the phase transition, in particular, quantities needed for Phase Field Modeling, such as the free energies of bulk phases and the phase transition front propagation velocity.

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Measuring Non-Market Values for Hydropower Production and Water Storage on the Colorado River: A White Paper Investigation

Lowry, Thomas S.; Chermak, Janie M.; Brookshire, David S.; Shaneyfelt, Calvin; Kobos, Peter

This study presents a conceptual framework for capturing the spatial and temporal aspects of non-market dimensions of value (DOV) and how they vary as the result of policy changes for hydropower generation and developed water uses. The foundation of this project is a literature review that reveals that focused, sector specific valuations are no longer adequate if the goal is to provide decision makers with a complete understanding of their decisions. Rather, estimates of non-market values for informing decisions regarding dam operations and/or other water management alternatives must consider the entire spectrum of market and non-market values, and the tradeoffs (both positive and negative) between those values over time and space, while considering shifting preferences in an uncertain environment. This document describes the history and reasoning for these conclusions and presents a conceptual framework for understanding non-market values as a function of changes to hydropower operations and water resources management.

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IDC Re-Engineering Phase 3 Budgetary Cost Estimate Summary (Leveraged NDC Case)

Harris, James M.; Burns, John F.; Pollock, David L.; Stevens, Maria E.; Stoddard, Mary C.

Sandia National Laboratories has prepared a budgetary cost estimate for planning for the IDC Re-engineering Phase 3 effort, based on leveraging a fully funded, Sandia executed NDC Modernization project. This report provides the budgetary cost estimate and describes the methodology, assumptions, and cost model details used to create the budgetary cost estimate.

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China-Pakistan Economic Corridor

Boyce, Tucker

International trade and related economic activities in Central and South Asia are increasing as developing economies, particularly India and Pakistan, grow. China continues to emerge as a major regional and global power and has embarked upon numerous regional economic and political initiatives . A major development is the China - Pakistan Economic Corridor (CPEC), a host of infrastructure and trade projects worth over 40 billion American dollars . This report analyzes CPEC a nd its potential regional effects, including the trade security implications of the port and land infrastructure developments . As trade increase s in the reg ion and the major CPEC infrastructure projects are completed, there will be numerous implications on trade security and geopolitics within South Asia. CPEC projects uniquely intersect numerous regional situations, including territorial disputes in Kashmir, the Afghanistan/Pakistan border, and Chinese foreign policy a mbitions. A nuanced understanding of these effects can influence future policy adjustments in this region . The views expressed in this report are those of the author and do not necessarily reflect the position of Sandia National Laboratories or the author's current and past institutions.

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Wave transmission through silicone foam pads in a compression Kolsky bar apparatus. Comparisons between simulations and measurements

Corona, Edmundo; Song, Bo

This memo concerns the transmission of mechanical signals through silicone foam pads in a compression Kolsky bar set-up. The results of numerical simulations for four levels of pad pre-compression and two striker velocities were compared directly to test measurements to assess the delity of the simulations. The nite element model simulated the Kolsky tests in their entirety and used the hyperelastic `hyperfoam' model for the silicone foam pads. Calibration of the hyperfoam model was deduced from quasi-static compression data. It was necessary, however, to augment the material model by adding sti ness proportional damping in order to generate results that resembled the experimental measurements. Based on the results presented here, it is important to account for the dynamic behavior of polymeric foams in numerical simulations that involve high loading rates.

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Cultural Artifact Detection in Long Wave Infrared Imagery

Anderson, Dylan Z.; Craven, Julia M.

Detection of cultural artifacts from airborne remotely sensed data is an important task in the context of on-site inspections. Airborne artifact detection can reduce the size of the search area the ground based inspection team must visit, thereby improving the efficiency of the inspection process. This report details two algorithms for detection of cultural artifacts in aerial long wave infrared imagery. The first algorithm creates an explicit model for cultural artifacts, and finds data that fits the model. The second algorithm creates a model of the background and finds data that does not fit the model. Both algorithms are applied to orthomosaic imagery generated as part of the MSFE13 data collection campaign under the spectral technology evaluation project.

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Framework for Shared Drinking Water Risk Assessment

Lowry, Thomas S.; Tidwell, Vincent C.; Peplinski, William J.; Mitchell, Roger; Binning, David; Meszaros, Jenny

Central to protecting our nation's critical infrastructure is the development of methodologies for prioritizing action and supporting resource allocation decisions associated with risk-reduction initiatives. Toward this need a web-based risk assessment framework that promotes the anonymous sharing of results among water utilities is demonstrated. Anonymous sharing of results offers a number of potential advantages such as assistance in recognizing and correcting bias, identification of 'unknown, unknowns', self-assessment and benchmarking for the local utility, treatment of shared assets and/or threats across multiple utilities, and prioritization of actions beyond the scale of a single utility. The constructed framework was demonstrated for three water utilities. Demonstration results were then compared to risk assessment results developed using a different risk assessment application by a different set of analysts.

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Systematic measurements of opacity dependence on temperature density and atomic number at stellar interior conditions

Bailey, James E.; Nagayama, Taisuke; Loisel, Guillaume P.; Rochau, G.A.; Blancard, C.; Colgan, J.; Cosse, Ph; Faussurier, G.; Fontes, C.J.; Gilleron, F.; Golovkin, I.; Hansen, Stephanie B.; Iglesias, C.A.; Kilcrease, D.P.; Macfarlane, Joseph J.; Mancini, Roberto C.; Nahar, S.N.; Orban, C.; Pain, J.C.; Pradhan, A.K.; Sherrill, M.; Wilson, B.G.

Abstract not provided.

Instrumentation Cables Test Plan

Muna, Alice B.; Lafleur, Angela (Chris)

The objective of this research is to better understand the fire-induced failure modes of instrumentation cables and evaluate the potential effect those failure modes could have on plant instrumentation circuits (i.e., circuit, component, and/or system response). In particular, this research is intended to better quantify the signal leakage that may occur before catastrophic failure in instrumentation circuits.

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Mechanisms for Ductile Rupture - FY16 ESC Progress Report

Boyce, Brad L.; Carroll, J.D.; Noell, Philip; Bufford, Daniel C.; Clark, Blythe C.; Hattar, Khalid M.; Lim, Hojun; Battaile, Corbett C.

Ductile rupture in metals is generally a multi-step process of void nucleation, growth, and coalescence. Particle decohesion and particle fracture are generally invoked as the primary microstructural mechanisms for room-temperature void nucleation. However, because high-purity materials also fail by void nucleation and coalescence, other microstructural features must also act as sites for void nucleation. Early studies of void initiation in high-purity materials, which included post-mortem fracture surface characterization using scanning electron microscopy (SEM) and high-voltage electron microscopy (HVEM) and in-situ HVEM observations of fracture, established the presence of dislocation cell walls as void initiation sites in high-purity materials. Direct experimental evidence for this contention was obtained during in-situ HVEM tensile tests of Be single crystals. Voids between 0.2 and 1 μm long appeared suddenly along dislocation cell walls during tensile straining. However, subsequent attempts to replicate these results in other materials, particularly α -Fe single crystals, were unsuccessful because of the small size of the dislocation cells, and these remain the only published in-situ HVEM observations of void nucleation at dislocation cell walls in the absence of a growing macrocrack. Despite this challenge, other approaches to studying void nucleation in high-purity metals also indicate that dislocation cell walls are nucleation sites for voids.

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Removing Dissolved Silica from Waste Water with Catechol and Active Carbon

Nenoff, Tina M.; Sasan, Koroush; Brady, Patrick V.; Krumhansl, James L.

Fresh water scarcity is going to be a global great challenge in the near future because of the increasing population. Our water resources are limited and, hence, water treatment and recycling methods are the only alternatives for fresh water procurement in the upcoming decades. Water treatment and recycling methods serve to remove harmful or problematic constituents from ground, surface and waste waters prior to its consumption, industrial supply, or other uses. Scale formation in industrial and domestic installations is still an important problem during water treatment. In water treatment, silica scaling is a real and constant concern for plant operations. The focus of this study is on the viability of using a combination of catechol and active carbon to remove dissolved silica from concentrated cooling tower water (CCTW). Various analytical methods, such as ICP-MS and UV-vis, were used to understand the structure-property relationship between the material and the silica removal results. UV-Vis indicates that catechol can react with silica ions and form a silica-catecholate complex. The speciation calculation of catechol and silica shows that catechol and silica bind in the pH range of 8 – 10; there is no evidence of linkage between them in neutral and acidic pHs. The silica removal results indicate that using ~4g/L of catechol and 10g/L active carbon removes up to 50% of the dissolved silica from the CCTW.

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Well Construction Details, Groundwater Elevations, and Figures for the Tijeras Arroyo Groundwater Area at Sandia National Laboratories, New Mexico

Copland, John R.

This Sandia National Laboratories / New Mexico (SNL/NM) submittal contains groundwater information that the United States Geological Survey (USGS) has requested. The USGS will use the information to assist Kirtland Air Force Base (KAFB) in its ongoing groundwater studies. The information in this submittal contains well-construction details and groundwater-elevation data for monitoring wells that SNL/NM has installed. Relevant well-construction data from other government agencies are also summarized. This submittal contains four data tables and three figures. Information in the tables has been used by SNL/NM to prepare groundwater compliance reports that have previously incorporated the three figures. The figures depict the potentiometric surface for the Perched Groundwater System, the potentiometric surface for the Regional Aquifer, and a Conceptual Site Model for the vicinity of Tijeras Arroyo in the northern portion of KAFB.

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Europa Lander Modeling Transport Capabilities Survey

Lane, Todd

The following trade study was done to answer the following task from the Sandia JPL Collaboration for Europa Lander Statement of Work: Survey SNL capabilities for modeling the transport and survivability of biological organisms in extremely hot, cold, and high radiation environments.

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[Europa Lander] Decontamination Methods Trade Study

Lane, Todd; Lane, Pamela

The following trade study was done to answer the following task from the Sandia JPL Collaboration for Europa Lander Statement of Work: Perform a trade study to assess the feasibility of other sterilization/decontamination methods for reducing forward biological contamination on S/C and assess their suitability for PP applications

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Radiation Testing at Sandia National Laboratories: Sandia – JPL Collaboration for Europa Lander

Olszewska-Wasiolek, Maryla A.; Hattar, Khalid M.

Sandia National Laboratories (SNL) is assisting Jet Propulsion Laboratory in undertaking feasibility studies and performance assessments for the Planetary Protection aspect of the Europa Lander mission. The specific areas of interest for this project are described by task number. This white paper presents the evaluation results for Task 2, Radiation Testing, which was stated as follows: Survey SNL facilities and capabilities for simulating the Europan radiation environment and assess suitability for: A. Testing batteries, electronics, and other component and subsystems B. Exposing biological organisms to assess their survivability metrics. The radiation environment the Europa Lander will encounter on route and in orbit upon arrival at its destination consists primarily of charged particles, energetic protons and electrons with the energies up to 1 GeV. The charged particle environments can be simulated using the accelerators at the Ion Beam Laboratory. The Gamma Irradiation Facility and its annex, the Low Dose Rate Irradiation Facility, offer irradiations using Co-60 gamma sources (1.17 and 1.33 MeV), as well as Cs-137 gamma (0.661 MeV) AmBe neutron (0-10 MeV) sources.

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Environmental Restoration Operations Consolidated Quarterly Report: July-September 2016

Cochran, John R.

This Environmental Restoration Operations (ER) Consolidated Quarterly Report (ER Quarterly Report) provides the status of ongoing corrective action activities being implemented at Sandia National Laboratories, New Mexico (SNL/NM) during the July, August, and September 2016 quarterly reporting period. The Solid Waste Management Units (SWMUs) and Areas of Concern (AOCs) identified for corrective action at SNL/NM are listed in Table I-1. Sections I.2.1 and I.2.2 summarize the work completed during this quarter. Section I.2.1 summarizes the quarterly activities at sites undergoing corrective action field activities. Field activities are conducted at the three groundwater AOCs (Burn Site Groundwater [BSG AOC], Technical Area [TA]-V Groundwater [TAVG AOC], and Tijeras Arroyo Groundwater [TAG AOC]). Section I.2.2 summarizes quarterly activities at sites where the New Mexico Environment Department (NMED) issued a certificate of completion and the sites are in the corrective action complete (CAC) regulatory process. Currently, SWMUs 8 and 58, 68, 149, 154, and 502 are in the CAC regulatory process. Corrective action activities are deferred at the Long Sled Track (SWMU 83), the Gun Facilities (SWMU 84), and the Short Sled Track (SWMU 240) because these three sites are active mission facilities. These three active sites are located in TA-III.

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Well Integrity for Natural Gas Storage in Depleted Reservoirs and Aquifers

Bauer, Stephen J.; Blankenship, Douglas A.; Roberts, Barry L.; Freifeld, Barry; Oldenburg, Curtis; Jordan, Preston; Perfect, Scott; Morris, Joseph; Bromhal, Grant; Glosser, Deborah; Wyatt, Douglas

Natural gas storage facilities are a critical component of our energy supply and distribution chain, allowing elasticity in gas supply to accommodate daily to seasonal demand fluctuations. As has been made evident by the recent Aliso Canyon Gas Storage facility incident, a loss of well integrity may result in significant consequences, including the prolonged shutdown of an entire facility. The Aliso Canyon gas well blowout emitted approximately 100,000 tonnes of natural gas (mostly methane) over 4 months and displaced thousands of nearby residents from their homes. The high visibility of the event has led to increased scrutiny of the safety of natural gas storage at the Aliso Canyon facility, led to questions about energy reliability, and raised broader concerns for natural gas storage integrity throughout the country.

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Custodial Services End of Year Report for 2016

Konetzni, Joshua B.

Sandia’s Custodial Services Department is a full-service, in-house custodial department. The department consists of one manager, four team supervisors, three administrative support personnel, 11 lead custodians, 71 day-shift custodians, four swing shift custodians, and eight heavy floor care personnel. The department services approximately 3.5 million square feet of office, lobby, laboratory, break room, classroom, and conference room space and assists with the collection of recycling products, including aluminum, plastic, card board box, and mixed paper products. Detailed in this report are audits, awards, and certifications; department highlights; departmental promotions; custodial metrics.

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In situ nucleophilic substitutional growth of methylammonium lead iodide polycrystals

Nature Chemistry

Alam, Todd M.; Acik, Muge; Guo, Fangmin; Ren, Yang; Lee, Byeongdu; Mitchell, Jf; Kinaci, Alper; Chan, Maria; Darling, Seth B.

Methylammonium lead iodide (MAPbIx) perovskites are organic-inorganic semiconductors that serve as the light-harvesting component of the photovoltaics, and are desirable with their long diffusion length yielding power conversion efficiencies of ≥22%. Conventional techniques grow perovskites by spin coating precursors on an oxide or a polymer substrate followed by annealing, however, use of high boiling point solvents and high temperatures hinder device stability and performance. Through a one-step, acid-catalyzed nucleophilic-substitutional crystal growth in polar protic solvents, we show evidence for the substrate- and annealing- free production of MAPbIx polycrystals that are metallic-lead-free with negligibly small amount of PbI2 precipitation (<10%). On the basis of this chemical composition, we have devised an in situ growth of highly air (upto ~1.5 months) and thermally-stable (≤300°C), tetragonal-phased, variable-sized polycrystals (~100 nm-10 μm) amendable for large-area deposition, and ultimately, large-scale manufacturing. This method is encouraging for stable optoelectronic devices, and leads to energy-efficient and low-cost processing.

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Chlorination of zirconium (0001) surface: A first-principles study

Chemical Physics Letters

Kim, Eunja; Weck, Philippe F.; Borjas, Rosendo; Poineau, Frederic

Here, the mechanisms and energetics of Zr(0001) surface chlorination by dissociative adsorption of gaseous Cl2, and associated speciation and surface degradation processes, have been investigated within the framework of density functional theory. Chlorination of Zr(0001) is predicted to be exothermic by ~3 eV/Cl for dissociative adsorption of a single Cl2 molecule, followed by exothermic chlorination to 1ML and 2 ML under Cl-rich conditions, with respective energy gains of 1.93 and 2.79 eV/Cl. Calculations also show that exfoliation of the top Cl-Zr-Cl sandwich layers is exothermic and most energetically favorable, and can thus be considered as a leading mechanism for Zr(0001) surface dissolution. Consistent with experimental findings, formation of ZrCl4 molecular products is also found to be dominant during Zr(0001) chlorination.

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Results 38001–38200 of 99,299
Results 38001–38200 of 99,299