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DOE OSTI2017

Dispersion of the refractive index in high-k dielectrics

A brief review of the optical properties of oxide materials that are used at present as dielectrics in modern microelectronics is presented. Using spectral ellipsometry, dispersion dependencies for different materials are measured. A brief comparative analysis of different dielectric coatings is carried out. The results of our research will be useful in further studies of the properties of dielectrics, as well as in technologies that are employed in the development of new semiconductor instruments and devices.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

DOE OSTI2018

Trinal Nature of the Excitation of Bulk Plasmons by a Fast Charged Particle at Grazing Incidence on the Interface between Vacuum and a Metal with Strong Spatial Dispersion

The excitation and propagation of bulk and surface (surface waves of transition radiation of plasmons at frequencies above the plasma frequency) plasma waves by incident electrons moving both in vacuum toward the surface of a metal and inside the metal whose boundary elastically and spectacularly reflects internal nonequilibrium electrons have been analyzed. In contrast to work [B. N. Libenson, J. Exp. Theor. Phys. 113, 553 (2011)], attention in this work is focused on the influence of surface effects on bulk-plasmon excitation by incident electrons. The probabilities and spectra of single characteristic energy loss of an intermediate- energy electron (50–500 eV) moving at an angle to the surface of the medium in three regions: in vacuum, in the medium, and again in vacuum after the electron leaves the medium are calculated. The kinetic approximation is used for the dielectric function, where the entire range of the plasmon spectrum is taken into account correctly for the problem under consideration. In the indicated energy range of incident electrons, surface effects, on the one hand, significantly reduces the probability of excitation of bulk plasma waves in the medium with strong spatial dispersion, in particular, as compared to the results obtained in [B.N. Libenson, J. Exp. Theor. Phys. 113, 553 (2011)], where surface effects were disregarded and the probability of bulkplasmon excitation by a 200-eV electron incident and emitted perpendicularly to the boundary is about one third of that in the unbounded medium. On the other hand, at grazing incidence from vacuum, the probability of transition radiation of bulk plasmons increases significantly and can lead to a change in the character of the angular dependence of the intensity of bulk plasma energy loss. Thus, the main result of this work is that a decrease in the glancing angle of the fast electron with respect to the vacuum–metal interface is accompanied both by an increase in the contribution from the transition mechanism to the probability of bulk-plasmon excitation in the vacuum region and by a decrease in the contribution from Cherenkov and bremsstrahlung mechanisms of excitation in the medium. The probability of bulk-plasmon excitation in the vacuum region exceeds the probability of excitation at the further motion of the electron in metallic aluminum at angles of incidence larger than 65°, 70°, and 75° at the energies E = 200, 350, and 500 eV, respectively.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

DOE OSTI2019

Dispersion of Lifetimes of Excited States of Single Molecules in Organic Matrices at Ultralow Temperatures

Fluorescence excitation spectra of single terrylene molecules in transparent naphthalene and polyethylene matrices at ultralow (30–100 mK) temperatures have been studied under the conditions where the widths of zero-phonon spectral lines are determined only by the lifetime T{sub 1} of the excited electronic state. The experimentally observed dispersion of T{sub 1} values for identical molecules is attributed to local field effects, which are responsible for the dependence of T{sub 1} on the effective value of refractive index n of the matrix, which is characteristic of the localization region of each molecule. It has been shown that the dependence T{sub 1}(n) for ensembles of point emitters in organic matrices is satisfactorily explained within the model of a “virtual cavity” around the emitter inside a continuous medium, as well as within the developed quantum kinetic approach including various contributions of the local environment to the lifetime T{sub 1}. The recalculation of average T{sub 1} values to the corresponding n values with the use of the expressions obtained for T{sub 1}(n) has shown that the difference of the calculated refractive indices of naphthalene and polyethylene from the well-known tabulated n values is less than 1%.

74 ATOMIC AND MOLECULAR PHYSICS↗

DOE OSTI2017

Ab initio calculations of phonon dispersion in CdGa{sub 2}Se{sub 4}

The density of phonon states and the phonon dispersion in the Brillouin zone are calculated by the density functional method of. The displacements of atoms in the elementary cell are constructed for vibrations of the A, B, and E symmetries. The calculated frequencies of optical phonons are consistent with the experimentally determined frequencies from the IR-absorption (infrared) and Raman-scattering spectra. In the xy plane, the intersection of low-frequency optical phonons with acoustic phonons is observed.

36 MATERIALS SCIENCE↗

DOE OSTI2021

Chirped laser dispersion spectroscopy for spectroscopic chemical sensing with simultaneous range detection

Spectroscopic chemical detection requires knowledge or determination of an optical path for accurate quantification of path-integrated concentration of species. Continuous- wave-laser-based spectroscopic systems operating in an open integrated-path remote sensing configuration are usually not equipped for optical path determination. Here we demonstrate a measurement technique capable of simultaneous spectroscopic chemical quantification and range finding. Here, the range-finding functionality is implemented with chirped laser dispersion spectroscopy. The methodology is potentially useful for remote chemical sensing in a hard-target LIDAR configuration and for automatic calibration of gas cells with unknown or varying lengths.

03 NATURAL GAS↗

DOE OSTI2014

Streamlined Approach for Environmental Restoration (SAFER) Plan for Corrective Action Unit 415: Project 57 No. 1 Plutonium Dispersion (NTTR), Nevada (Revision 0)

This Streamlined Approach for Environmental Restoration (SAFER) Plan addresses the actions needed to achieve closure for Corrective Action Unit (CAU) 415, Project 57 No. 1 Plutonium Dispersion (NTTR). CAU 415 is located on Range 4808A of the Nevada Test and Training Range (NTTR) and consists of one corrective action site: NAFR-23-02, Pu Contaminated Soil. The CAU 415 site consists of the atmospheric release of radiological contaminants to surface soil from the Project 57 safety experiment conducted in 1957. The safety experiment released plutonium (Pu), uranium (U), and americium (Am) to the surface soil over an area of approximately 1.9 square miles. This area is currently fenced and posted as a radiological contamination area. Vehicles and debris contaminated by the experiment were subsequently buried in a disposal trench within the surface-contaminated, fenced area and are assumed to have released radiological contamination to subsurface soils. Potential source materials in the form of pole-mounted electrical transformers were also identified at the site and will be removed as part of closure activities.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2014

QUIC: A Fast-Running High-Resolution 3D Building-Aware Urban Transport and Dispersion Modeling System

Transport and dispersion of airborne contaminants in urban environments is extremely complicated. Buildings alter the flow fields and deflect the wind, causing updrafts and downdrafts, channeling between buildings, areas of calm winds adjacent to strong winds, and horizontally and vertically rotating-eddies between buildings, at street corners, and other places within the urban canopy. High concentrations of fine particulate matter or carbon monoxide over short time periods can result from vehicle emissions that become trapped between tall buildings in urban areas. Toxic industrial chemicals are often transported via railcar and trucks near or through cities and stored among buildings and other structures at industrial and manufacturing sites that are sometimes found in or near inhabited locations. In addition to accidental releases, there is also concern of pre-meditated chemical, biological, and radiological attacks in cities.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2015

Streamlined Approach for Environmental Restoration (SAFER) Plan for Corrective Action Unit 411: Double Tracks Plutonium Dispersion (Nellis), Nevada Test and Training Range, Nevada (Rev. 0)

This Streamlined Approach for Environmental Restoration (SAFER) Plan addresses the actions needed to achieve closure for Corrective Action Unit (CAU) 411, Double Tracks Plutonium Dispersion (Nellis). CAU 411 is located on the Nevada Test and Training Range and consists of a single corrective action site (CAS), NAFR-23-01, Pu Contaminated Soil. There is sufficient information and historical documentation from previous investigations and the 1996 interim corrective action to recommend closure of CAU 411 using the SAFER process. Based on existing data, the presumed corrective action for CAU 411 is clean closure. However, additional data will be obtained during a field investigation to document and verify the adequacy of existing information, and to determine whether the CAU 411 closure objectives have been achieved. This SAFER Plan provides the methodology to gather the necessary information for closing the CAU. The results of the field investigation will be presented in a closure report that will be prepared and submitted to the Nevada Division of Environmental Protection (NDEP) for review and approval. The site will be investigated based on the data quality objectives (DQOs) developed on November 20, 2014, by representatives of NDEP, the U.S. Air Force (USAF), and the U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Field Office. The DQO process was used to identify and define the type, amount, and quality of data needed to determine whether CAU 411 closure objectives have been achieved. The following text summarizes the SAFER activities that will support the closure of CAU 411; Collect environmental samples from designated target populations to confirm or disprove the presence of contaminants of concern (COCs) as necessary to supplement existing information; If COCs are no longer present, establish clean closure as the corrective action; If COCs are present, the extent of contamination will be defined and further corrective actions will be evaluated with the stakeholders (NDEP, USAF); and Confirm the preferred closure option is sufficient to protect human health and the environment.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2015

Corrective Action Decision Document for Corrective Action Unit 568. Area 3 Plutonium Dispersion Sites, Nevada National Security Site, Nevada Revision 0

The purpose of this Corrective Action Decision Document is to identify and provide the rationale for the recommendation of corrective action alternatives (CAAs) for the 14 CASs within CAU 568. Corrective action investigation (CAI) activities were performed from April 2014 through May 2015, as set forth in the Corrective Action Investigation Plan for Corrective Action Unit 568: Area 3 Plutonium Dispersion Sites, Nevada National Security Site, Nevada; and in accordance with the Soils Activity Quality Assurance Plan, which establishes requirements, technical planning, and general quality practices. The purpose of the CAI was to fulfill data needs as defined during the DQO process. The CAU 568 dataset of investigation results was evaluated based on a data quality assessment. This assessment demonstrated that the dataset is complete and acceptable for use in fulfilling the DQO data needs. Based on the evaluation of analytical data from the CAI, review of future and current operations at the 14 CASs, and the detailed and comparative analysis of the potential CAAs, the following corrective actions are recommended for CAU 568: • No further action is the preferred corrective action for CASs 03-23-17, 03-23-22, 03-23-26. • Closure in place is the preferred corrective action for CAS 03-23-19; 03-45-01; the SE DCBs at CASs 03-23-20, 03-23-23, 03-23-31, 03-23-32, 03-23-33, and 03-23-34; and the Pascal-BHCA at CAS 03-23-31. • Clean closure is the preferred corrective action for CASs 03-08-04, 03-23-30, and 03-26-04; and the four well head covers at CASs 03-23-20, 03-23-23, 03-23-31, and 03-23-33.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2015

Wavelength Dispersive X-ray Fluorescence Analysis of Actinides in Dissolved Nuclear Fuels

There is an urgent need for an instrument that can quickly measure the concentration of Plutonium and other Actinides mixed with Uranium in liquids containing dissolved spent fuel rods. Parallax Research, Inc. proposes to develop an x-ray spectrometer capable of measuring U, Np and Pu in dissolved nuclear fuel rod material to less than 10 ppm levels to aid in material process control for these nuclear materials. Due to system noise produced by high radioactivity, previous x-ray spectrometers were not capable of low level measurements but the system Parallax proposed has no direct path for undesired radiation to get to the detector and the detector in the proposed device is well shielded from scatter and has very low dark current. In addition, the proposed spectrometer could measure these three elements simultaneously, also measuring background positions with an energy resolution of roughly 100 eV making it possible to see a small amount of Pu that would be hidden under the tail of the U peak in energy dispersive spectrometers. Another nearly identical spectrometer could be used to target Am and Cm if necessary. The proposed spectrometer needs only a tiny sample of roughly 1 micro-liter (1 mm 3 ) and the measurement can be done with the liquid flowing in a radiation and chemical immune quartz capillary protected by a stainless steel rod making it possible to continuously monitor the liquid or to use a capillary manifold to measure other liquid streams. Unlike other methods such as mass spectroscopy where the sample must be taken to a remote facility and might take days for turn-around, the proposed measurement should take less than an hour. This spectrometer could enable near real-time measurement of U, Pu and Np in dilute dissolved spent nuclear fuel rod streams.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

DOE OSTI2016

Corrective Action Investigation Plan for Corrective Action Unit 413: Clean Slate II Plutonium Dispersion (TTR) Tonopah Test Range, Nevada (Rev. 1)

Corrective Action Unit (CAU) 413 is located on the Tonopah Test Range, which is approximately 130 miles northwest of Las Vegas, Nevada, and approximately 40 miles southeast of Tonopah, Nevada. The CAU 413 site consists of the release of radionuclides to the surface and shallow subsurface from the conduct of the Clean Slate II (CSII) storage–transportation test conducted on May 31, 1963. CAU 413 includes one corrective action site (CAS), TA-23-02CS (Pu Contaminated Soil). The known releases at CAU 413 are the result of the atmospheric deposition of contamination from the 1963 CSII test. The CSII test was a non-nuclear detonation of a nuclear device located inside a reinforced concrete bunker covered with 2 feet of soil. This test dispersed radionuclides, primarily plutonium, on the ground surface. The presence and nature of contamination at CAU 413 will be evaluated based on information collected from a corrective action investigation (CAI). The investigation is based on the data quality objectives (DQOs) developed on June 17, 2015, by representatives of the Nevada Division of Environmental Protection; the U.S. Air Force; and the U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Field Office. The DQO process was used to identify and define the type, amount, and quality of data needed to develop and evaluate appropriate corrective actions for CAU 413. The CAI will include radiological surveys, geophysical surveys, collection and analyses of soil samples, and assessment of investigation results. The collection of soil samples will be accomplished using both probabilistic and judgmental sampling approaches. To facilitate site investigation and the evaluation of DQO decisions, the releases at CAU 413 have been divided into seven study groups.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2016

Novel Nano-Size Oxide Dispersion Strengthened Steels Development through Computational and Experimental Study

This report summarizes our recent works of theoretical modeling, simulation and experimental validation of the simulation results on the ferritic oxide dispersion strengthened (ODS) alloy research. The simulation of the stability and thermal dynamics simulation on potential thermal stable candidates were performed and related ODS samples were synthesized and characterized. The simulation methods and experimental texture validation techniques development, achievements already reached, course work development, students and postdoc training, and future improvement are briefly introduced.

01 COAL, LIGNITE, AND PEAT↗

DOE OSTI2017

Corrective Action Decision Document/Corrective Action Plan for Corrective Action Unit 413: Clean Slate II Plutonium Dispersion (TTR) Tonopah Test Range, Nevada. Revision 0

This Corrective Action Decision Document/Corrective Action Plan provides the rationale and supporting information for the selection and implementation of corrective actions at Corrective Action Unit (CAU) 413, Clean Slate II Plutonium Dispersion (TTR). CAU 413 is located on the Tonopah Test Range and includes one corrective action site, TA-23-02CS. CAU 413 consists of the release of radionuclides to the surface and shallow subsurface from the Clean Slate II (CSII) storage–transportation test conducted on May 31, 1963. The CSII test was a non-nuclear detonation of a nuclear device located inside a concrete bunker covered with 2 feet of soil. To facilitate site investigation and the evaluation of data quality objectives decisions, the releases at CAU 413 were divided into seven study groups: 1 Undisturbed Areas 2 Disturbed Areas 3 Sedimentation Areas 4 Former Staging Area 5 Buried Debris 6 Potential Source Material 7 Soil Mounds Corrective action investigation (CAI) activities, as set forth in the CAU 413 Corrective Action Investigation Plan, were performed from June 2015 through May 2016. Radionuclides detected in samples collected during the CAI were used to estimate total effective dose using the Construction Worker exposure scenario. Corrective action was required for areas where total effective dose exceeded, or was assumed to exceed, the radiological final action level (FAL) of 25 millirem per year. The results of the CAI and the assumptions made in the data quality objectives resulted in the following conclusions: The FAL is exceeded in surface soil in SG1, Undisturbed Areas; The FAL is assumed to be exceeded in SG5, Buried Debris, where contaminated debris and soil were buried after the CSII test; The FAL is not exceeded at SG2, SG3, SG4, SG6, or SG7. Because the FAL is exceeded at CAU 413, corrective action is required and corrective action alternatives (CAAs) must be evaluated. For CAU 413, three CAAs were evaluated: no further action, clean closure, and closure in place. The CAAs were evaluated on technical merit focusing on performance, reliability, feasibility, safety, and cost. Based on the evaluation of analytical data from the CAI, review of future and current operations at CAU 413, and the detailed and comparative analysis of CAAs, clean closure was selected as the preferred CAA for CAU 413 by the U.S. Air Force, Nevada Division of Environmental Protection, and U.S. Department of Energy at the CAA meeting held on August 24, 2016.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2018

Corrective Action Decision Document/Corrective Action Plan for Corrective Action Unit 414: Clean Slate III Plutonium Dispersion (TTR) Tonopah Test Range, Nevada, Revision 1

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2018

Closure Report for Corrective Action Unit 413: Clean Slate II Plutonium Dispersion (TTR) Tonopah Test Range, Nevada, Revision 0

This Closure Report (CR) presents information supporting the closure of Corrective Action Unit (CAU) 413: Clean Slate II Plutonium Dispersion (TTR), located on the Tonopah Test Range, Nevada. CAU 413 consists of the release of radionuclides to the surface and shallow subsurface from the conduct of the Clean Slate II storage-transportation test conducted on May 31, 1963. The purpose of this CR is to provide documentation and justification for the clean closure of CAU 413 under the FFACO without further corrective action. This justification is based on historical knowledge of the site, previous site investigations, closure activities conducted at the site, and the results of verification samples. Clean closure activities included excavating and disposing of radiologically contaminated soil and debris in the vicinity of ground zero, and collecting verification samples to support the corrective action of clean closure. Results confirmed that further corrective action is not required at CAU 413. Based on the corrective action activities conducted, clean closure of the site is complete; the closure objectives established in the CADD/CAP have been achieved; and no further corrective action at the site is required.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2021

Remote methane sensor for emissions from pipelines and compressor stations using chirped-laser dispersion spectroscopy

Leak rates of methane (CH 4 ) from the natural gas supply chain result in lost profit from unsold product, public safety and property concerns due to potential explosion hazards, and a potentially large source of economic damages from legal liabilities. Yet large measurement challenges exist in identifying and quantifying CH 4 leak rates along the vast number and type of components in the natural gas supply chain. This is particularly true of the “midstream” components involved in the gathering, processing, compression, transmission, and storage of natural gas. This project developed and deployed new advances in chirped laser dispersion spectroscopy (CLaDS) to detect methane leaks from pipelines, compressor stations, and other midstream infrastructure from a remote position (standoff detection). The system was deployed from a van to measure fugitive methane leaks from a local compressor station as a proof-of-concept. The technique was validated through mobile laboratory measurements with in-situ sensors as well as controlled releases of methane. The system also mapped a plume from a controlled release of methane by tracking a small unmanned aerial system (sUAS) that carried a corner cube retroreflector which reflected the beam back to the instrument. The drone-based system quantified a leak rate to within 30% of the actual rate and localized the emission location within 5 m of the actual release location at standoff distances of 25-45 m. This sUAS-reflector tracking approach has benefits for mapping leak locations remotely using small drones flying around a facility. Benefits of a commercial sensor with these capabilities include reductions of leaks for pipeline operators (more profit), earlier detection of leaks to avoid catastrophic explosion hazards for public health and to mitigate property damage, and reduced methane emissions to the atmosphere (improving air quality).

03 NATURAL GAS↗

DOE OSTI2023

A Comparison of Adverse Meteorology Inputs for Emergency Management and Safety Basis Dispersion Modeling Applications at SRS

The MELCOR Accident Consequence Calculation System (MACCS), used for safety basis accident analyses at SRS, implements adjustment factors to consider the increased vertical turbulence associated with local surface roughness and the increased lateral turbulence associated with time-based plume meander. The two models used for SRS emergency planning radiological consequence assessment, i.e., Hotspot and Puff/Plume, currently do not have an option to input or apply diffusion adjustments for meander or surface roughness. Adverse meteorology conditions at SRS have been determined as E stability class and 1.3 meters per second wind speed for ground level releases. This is the input used for emergency planning models. Contrastingly safety basis analyses use a different input, representing adverse meteorology values as F stability class and wind speeds of 1.3 meters per second (for a ground level release). This results in an apparent discrepancy between the two approaches. In this report we document the differing modeling assumptions, discuss the logic behind each modeling approach used to represent local roughness and plume meander conditions, and numerically compare dispersion coefficients and concentration estimates obtained from each set of model inputs.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2025

Closure Report for Corrective Action Unit 366: Area 11 Plutonium Valley Dispersion Sites, Nevada National Security Site, Nevada with ROTC 1

This Closure Report presents information supporting closure of Corrective Action Unit (CAU) 366, Area 11 Plutonium Valley Dispersion Sites, and provides documentation supporting the completed corrective actions and confirmation that closure objectives for CAU 366 were met. CAU 366 consists of the following six Corrective Action Sites (CASs), located in Area 11 of the Nevada National Security Site: • CAS 11-08-01, Contaminated Waste Dump #1 • CAS 11-08-02, Contaminated Waste Dump #2 • CAS 11-23-01, Radioactively Contaminated Area A • CAS 11-23-02, Radioactively Contaminated Area B • CAS 11-23-03, Radioactively Contaminated Area C • CAS 11-23-04, Radioactively Contaminated Area D

54 ENVIRONMENTAL SCIENCES↗