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At least 37 records · Page 2

Materials Data on SrS by Materials Project

SrS is Halite, Rock Salt structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Sr2+ is bonded to six equivalent S2- atoms to form a mixture of corner and edge-sharing SrS6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Sr–S bond lengths are 3.03 Å. S2- is bonded to six equivalent Sr2+ atoms to form a mixture of corner and edge-sharing SSr6 octahedra. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗

Visualization of a Limonene Synthesis Metabolon Inside Living Bacteria by Hyperspectral SRS Microscopy

Abstract Monitoring biosynthesis activity at single‐cell level is key to metabolic engineering but is still difficult to achieve in a label‐free manner. Using hyperspectral stimulated Raman scattering imaging in the 670–900 cm −1 region, localized limonene synthesis are visualized inside engineered Escherichia coli . The colocalization of limonene and GFP‐fused limonene synthase is confirmed by co‐registered stimulated Raman scattering and two‐photon fluorescence images. The finding suggests a limonene synthesis metabolon with a polar distribution inside the cells. This finding expands the knowledge of de novo limonene biosynthesis in engineered bacteria and highlights the potential of SRS chemical imaging in metabolic engineering research.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

On the equivalence between SRS and PCO formulations of superstring perturbation theory

We establish the equivalence between two formulations of superstring perturbation theory, one based on integration over the supermoduli space of super Riemann surfaces (SRS), the other based on integration over the bosonic moduli space with insertions of picture changing operators (PCO) on the worldsheet and the vertical integration prescription, by showing how the latter arises from a specific construction of the supermoduli integration contour.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Treatment of WHO Grade 2 Meningiomas With Stereotactic Radiosurgery: Identification of an Optimal Group for SRS Using RPA

This study assesses a large multi-institutional database to present the outcomes of World Health Organization grade 2 meningiomas treated with stereotactic radiosurgery (SRS). We also compare the 3-year progression-free survival (PFS) to that reported in the Radiation Therapy Oncology Group 0539 phase 2 cooperative group meningioma trial.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Friend or Foe: Draft Genome Sequence of Bradyrhizobium sp. Strain SRS-191

We report the genomic features of Bradyrhizobium sp. strain SRS-191, which was isolated from a former nuclear legacy site in Aiken, South Carolina, USA. With a genome size of 7,621,400 bp, the strain harbored genes not only for environmentally beneficial traits (e.g., heavy metal resistance, nitrogen fixation, and aromatic biodegradation) but also for antimicrobial resistance.

Chauhan, Ashvini↗

AmeriFlux US-SRS Santa Rita Experimental Range Mesquite Savanna

This is the AmeriFlux version of the carbon flux data for the site US-SRS Santa Rita Experimental Range Mesquite Savanna. Site Description - The study site is located in the Santa Rita Experimental Range, approximately 45 km south of Tucson, Arizona, within the Sonoran Desert. The rangeland has undergone a shift from a semiarid grassland to a savanna due to the encroachment of the woody leguminous tree Prosopis velutina Woot., or velvet mesquite. A pair of adjacent watersheds of similar size ( 1.08 ha and 1.10 ha) was established to investigate the effects of mesquite removal on hydrologic processes. In 1974, diesel oil was applied basally to all trees in one watershed, with reapplication as needed and dead tree removal for wood, whereas the other watershed, where the flux tower is located, has continued in the woody plant encroachment process. In 2016, an herbicide process was applied to the area around the EC flux tower.

Vivoni, Enrique R.↗

Statistical Analysis of Imaging Laser Scan Data of an Exhaust Tunnel at the SRS

• The SRS H-Canyon Building is a critical facility under the responsibility of DOE-EM. • It includes an Air Exhaust Tunnel (HCAEX) that allows for ventilation of the process airflow. • Inspections are performed remotely because of hazards, e.g. radioactivity, debris, high airflow, and nitric acid vapors.

Wells, William Willie [Savannah River National Lab↗

Innovative Biomonitoring and Remediation of Heavy Metals Using Phytotechnologies at the Savannah River Site (SRS) Coal Combustion Product (CCP) Impoundment Sites

The Savannah River Site (SRS) contains legacy coal combustion product (CCP) impoundments that are impacted by elevated concentrations of heavy metals and radionuclides, posing long-term risks to soil health, ecosystem functioning, and environmental sustainability. Traditional environmental monitoring approaches rely primarily on chemical analyses to quantify contaminant concentrations but often provide limited information regarding biological responses or ecosystem recovery. This project addressed these limitations by integrating environmental chemistry, microbial ecology, artificial intelligence (AI), and bioremediation into a comprehensive framework for environmental diagnostics and restoration of contaminated soils. The overarching goal of this collaborative project between Florida A&M University (FAMU) and the University of Georgia's Savannah River Ecology Laboratory (SREL) was to develop innovative biomonitoring and remediation strategies for heavy metal-contaminated CCP impoundment sites at the Savannah River Site. Specifically, the project sought to (i) characterize heavy metal contamination, (ii) determine microbial responses to contamination, (iii) isolate indigenous heavy metal-resistant microorganisms for remediation applications, (iv) develop a microbial ecological health index using machine learning, and (v) optimize fungal-mediated bioremediation using artificial intelligence.

01 COAL, LIGNITE, AND PEAT↗

Inspection and Mapping of Savannah River Site (SRS) Waste Tanks via Unmanned Aircraft System (UAS) – 25351

The CSTF at SRS contain 51 waste tanks with 8 closed waste tanks between FTF and HTF. SRMC is the LW contractor. The LW mission includes removing legacy nuclear waste from these tanks and treating it for final disposition. Once the bulk of the waste has been removed from a tank, it will undergo inspection and sampling to characterize the remaining waste in the tank prior to it being operationally closed. There are multiple points in the tank closure process where an inspection is performed, and there are multiple parts of a tank that get inspected. Waste tanks have a primary containment vessel (referred to as the “Primary”) and a secondary containment vessel (referred to as the “Annulus”) that surrounds the primary. Both of these sections of a tank receive multiple inspections throughout the closure process.

Murphy, Lucas D. [Savannah River Mission Completio↗

Proton nuclear magnetic resonance (1H NMR) of flammable organic chemicals in radioactive high–level supernatant waste at the Savannah River Site (SRS)

The Savannah River Site stores approximately 36 million gallons of radioactive and hazardous waste that contains approximately 245 million curies. The waste is sent through various chemical processes to reduce its volume and to separate various components. The facility plans to replace formic acid (a chemical used to reduce soluble mercury) with glycolic acid. Recycle solution with glycolate may flow back to the tank farm, where the glycolate can generate hydrogen gas by thermal and radiolytic mechanisms. The current analytical method for detecting glycolate (ion chromatography) in supernatant requires a large dilution to reduce interference from the nitrate anions. Hydrogen nuclear magnetic resonance is an analytical method that requires less sample dilution. It takes advantage of the CH 2 group in glycolate. Liquid samples were spiked with four different levels of glycolate to build a calibration line, as it is recommended in the standard addition method. The detection and quantitation limits determined were 1 and 5 ppm, respectively, for 32 scans, which is well below the process limit of 10 ppm. In one test, 800 scans of a supernatant spiked with 1 ppm glycolate resulted in a -CH 2 peak with a signal-to-noise ratio of 36.

1H↗

Decreasing the amplitude of macroscopic quantum fluctuations in the case of transient SRS

It is shown experimentally that, under the conditions of transient stimulated Raman scattering, pumping by two successive orthogonally polarised laser pulses makes it possible to reduce the amplitude of macroscopic quantum energy fluctuations of a Stokes pulse by a factor of 4 in comparison with single-shot pumping. An energy dispersion of 0.9 % for the first Stokes component is obtained in hydrogen at a relative energy dispersion of ytterbium laser pulses of 0.4 %. (nonlinear optical phenomena)

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

Groundwater and surface water head from 2019 to 2022 at the Tims Branch in Savannah River Site (SRS), South Carolina.

This dataset contains groundwater and surface water head measurements for investigating hydro-biogeochemical processes in Tims Branch at the Savannah River Site, SC. Water levels were monitored using pressure transducers installed in surface water gauges and piezometers across three subsites in Tims Branch, identified as Wfloc, Snon (Snon1 and Snon2), and Sfloc. A barometric pressure logger was deployed in piezometers to correct pressure transducers from atmospheric pressure. Manual water level measurements were taken to calibrate transducer data. The dataset consists of at least paired groundwater and surface water head time series for each subsite, provided as individual CSV files. These data support analyses of surface-groundwater interactions, hydrologic controls on redox processes, and broader synthesis of wetland hydrology at the Savannah River Site.

ESS-DIVE CSV File Formatting Guidelines Reporting ↗

Quantitative Determination of Total Cesium in Savannah River Site (SRS) Tank Waste by Inductively Coupled Plasma Emission Spectroscropy

Utilization of the significant and unique wavelength dynamic range (165 to 1100 nm) available on the Leeman Prodigy Inductively Coupled Plasma Emission Spectroscopy (ICP-ES) allows for quantification of cesium using the emission line 894.347 nm without the potential of Barium interference in nuclear waste samples. Samples are added to a Sodium Peroxide Fusion and Lithium Carbonate buffer in 2% nitric acid solution to increase sensitivity of the easily ionizable (<6 eV) cesium for quantitation to 5 pbb. Through direct comparison of analytical data results, the method is proven to be complementary to the Inductively Coupled Plasma Mass Spectrometry (ICP-MS) analysis (LOQ 100 ppt) in support of the Department of Energy’s (DOE) Nuclear Waste Mission.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Cesium Batch Contact Equilibrium Testing of Crystalline Silicotitanate (CST) Sieve Cuts in SRS Average Simulant and Examination of CST Samples Aged in Caustic and Simulant in Support of Tank Closure Cesium Removal 1A (TCCR-1A)

Batch contact testing to determine cesium equilibrium loading on Crystalline Silicotitanate ion exchange media in Savannah River Site Average Waste Simulant at 25 °C indicated that smaller diameter particles isolated by sieving pretreated CST media may load slightly higher (<10%) amounts of cesium, though the differences are within analytical uncertainty. In addition, ion exchange media sub-samples stored in 2-4 M NaOH and caustic simulant solutions for ~2.5 years were examined by optical microscopy and the 3 M NaOH sample was also analyzed to determine whether changes in the particle size distribution occurred during storage. No visual indications of particle attrition or agglomeration were observed for any sample. Particle size analysis indicated that a slight decrease occurred in the average particle diameter following contact with 3 M NaOH (541 µm average diameter versus 566 µm for the pretreated CST prior to contact). A small increase (from 0 to <0.5 wt. %) in the number of particles ranging from 271 and 322 µm was also observed for the CST sample contacted with 3 M NaOH relative to a sample of the original pretreated material. However, this small change could be due to sub-sampling differences or analytical uncertainty. It does not appear that small particles are formed to a significant degree during CST caustic contact or that small particles which do form (presumably from attrition of larger particles during pretreatment) load significantly more cesium than the bulk material. Minimal other negative consequences were observed associated with CST extended caustic or simulant contact, except for the tendency for more concentrated salt solutions to form some salt crystals which deposit on the media over time.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Sorption of Iodine Species on SRS Wetland Soils

This research work has been supported by the DOE-FIU Science & Technology Workforce Development Initiative, an innovative program developed by the U.S. Department of Energy’s Office of Environmental Management (DOE-EM) and Florida International University’s Applied Research Center (FIU-ARC). During the summer of 2021, a DOE Fellow intern, Phuong Pham, spent 10 weeks doing a summer internship at Savannah River National Laboratory under the supervision and guidance of Hansell Gonzalez-Raymat. The intern’s project was initiated on May 24, 2021, and continued through July 30, 2021, with the objective of gaining a better understanding of the dominant attenuation mechanisms for 129 I in the wetlands, the strength of the attenuation, and what conditions would influence it.

54 ENVIRONMENTAL SCIENCES↗

Results of Re-evaluation of FEPs Related to Higher Fissile Content in HLW Glass at SRS

One of the objectives of the United States Department of Energy Office of Nuclear Energy’s Office of Spent Fuel and High-Level Waste Disposition is to better understand the technical bases, risks, and uncertainties associated with the safe and secure disposition of spent nuclear fuel and high-level radioactive waste. Domestic defense and research activities have generated a few thousand metric tons of spent nuclear fuel and high-level radioactive waste, much of which has been or will be processed and vitrified into high-level waste glass. The Nuclear Waste Policy Act 1982 makes the Department of Energy responsible for disposal of these materials.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗