Constraining natural gas pipeline emissions in San Juan Basin using mobile sampling
Not Available
Li, Hugh Z.↗
SEARCH · Engineering Papers
Results for “sans”
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Different agglomeration properties of PC 61 BM and PC 71 BM in photovoltaic inks – a spin-echo SANS study
Fullerene derivatives are used in a wide range of applications including as electron acceptors in solution-processable organic photovoltaics. We report agglomeration of fullerene derivatives in optically opaque solutions of PC 61 BM and PC 71 BM, with concentrations ranging from 30 mg mL -1 up to 90 mg mL -1 , in different solvents with relevance to organic photovoltaics, using a novel neutron scattering technique, Spin-Echo Small Angle Neutron Scattering (SESANS). From SESANS, agglomerates with correlation lengths larger than 1 μm are found in some PC 61 BM solutions, in contrast no agglomerates are seen in PC 71 BM solutions. These results clearly show that PC 71 BM is fundamentally more soluble than PC 61 BM in the solvents commonly used in photovoltaic inks and corroborating similar observations previously achieved using other experimental techniques. Computer models are presented to study the energetics of solution and agglomeration of both species, ascribing the difference to a kinetic effect probably related to the larger anisotropy of PC 71 BM. Also, this work showcases the power of SESANS to probe agglomerates of fullerene derivatives in completely opaque solutions for agglomerates of the order of one to several microns.
36 MATERIALS SCIENCE↗
Knowledge gaps, water caps and regulatory traps: policies, practices, and lessons from environmental flow requirements in the San Joaquin River, California
Not Available
Dourado, Gustavo Facincani (ORCID:0000000270836351↗
Network analysis of earthquake ground motion spatial correlation: a case study with the San Jacinto seismic nodal array
SUMMARY The spatial correlation of earthquake ground motion intensity can be measured from strong motion data; however, the data used in past studies is sparsely sampled in space, and only the interstation distance was considered as a correlation variable. These limitations mean that we have only weak constraints on the true correlation structure of ground motion and that potentially important aspects of spatial correlation are unconstrained. In this study, we combine a large-N seismic array and graph analytics to explore this issue at a local scale using small local and regional earthquakes. Our result suggests site conditions, and how they interact with the incident seismic wavefield, strongly condition the spatial correlation of ground motion. Future progress in characterizing ground motion spatial variability will require dense wavefield measurements, either through nodal deployments, or perhaps distributed acoustic sensing measurements, of seismic wavefields. Aftershock sequences of major earthquakes would provide particularly data-rich targets of opportunity.
58 GEOSCIENCES↗
Root Cause Analysis of AC Overcurrent in July 2020 San Fernando Disturbance
On July 7 2020, approximately 1,000 MW reduction in solar photovoltaic (PV) output was experienced by the bulk power system in Southern California after a three-phase fault. Disturbance analysis indicates that instantaneous AC current caused inverter tripping. The projection of the root cause of AC overcurrent from the NERC report is that inverter current control is not tight. This letter provides a quantitative analysis on ac overcurrent and addresses the following questions: (i) what type of current controls may lead to ac overcurrent; and (ii) how controller parameters and grid strength influence ac overcurrent. Here, the letter provides frequency-domain analysis and time-domain simulation results of a grid-integrated inverter to illustrate the effect of control parameters and grid strength on ac overcurrent.
14 SOLAR ENERGY↗
Decomposing a San Francisco estuary microbiome using long-read metagenomics reveals species- and strain-level dominance from picoeukaryotes to viruses
ABSTRACT Although long-read sequencing has enabled obtaining high-quality and complete genomes from metagenomes, many challenges still remain to completely decompose a metagenome into its constituent prokaryotic and viral genomes. This study focuses on decomposing an estuarine metagenome to obtain a more accurate estimate of microbial diversity. To achieve this, we developed a new bead-based DNA extraction method, a novel bin refinement method, and obtained 150 Gbp of Nanopore sequencing. We estimate that there are ~500 bacterial and archaeal species in our sample and obtained 68 high-quality bins (>90% complete, <5% contamination, ≤5 contigs, contig length of >100 kbp, and all ribosomal and tRNA genes). We also obtained many contigs of picoeukaryotes, environmental DNA of larger eukaryotes such as mammals, and complete mitochondrial and chloroplast genomes and detected ~40,000 viral populations. Our analysis indicates that there are only a few strains that comprise most of the species abundances. IMPORTANCE Ocean and estuarine microbiomes play critical roles in global element cycling and ecosystem function. Despite the importance of these microbial communities, many species still have not been cultured in the lab. Environmental sequencing is the primary way the function and population dynamics of these communities can be studied. Long-read sequencing provides an avenue to overcome limitations of short-read technologies to obtain complete microbial genomes but comes with its own technical challenges, such as needed sequencing depth and obtaining high-quality DNA. We present here new sampling and bioinformatics methods to attempt decomposing an estuarine microbiome into its constituent genomes. Our results suggest there are only a few strains that comprise most of the species abundances from viruses to picoeukaryotes, and to fully decompose a metagenome of this diversity requires 1 Tbp of long-read sequencing. We anticipate that as long-read sequencing technologies continue to improve, less sequencing will be needed.
Lui, Lauren M.↗
Sap flow data from San Lorenzo, Panama (PA-SLZ) from January - June 2020
Explore the source record for details and available documents.
Pivovaroff, Alexandria↗
Leaf gas exchange (BNL-PNNL collaboration), San Lorenzo, Panama, 2020
This data package contains Photosynthetic CO2 response (ACi curves) and Light Response (AQ) of mature sunlit canopy leaves of 11 species from PA-SLZ, February 2020. Branches were cut from the top of the canopy and re-cut under water. Fitted Vcmax and Jmax photosynthetic parameters were derived from measured data as well as the convexity, light use efficiency and apparent quantum yield. This data was collected as a collaboration between Brookhaven National Laboratory (BNL) and Pacific Northwest National Laboratory (PNNL), and is a subset of the 2020 BNL Panama campaign. The species included in this dataset are: Apeiba membranacea, Carapa guianensis, Cespedesia spathulate, Jacaranda copaia, Lonchocarpus heptaphyllus, Pera arboea, Pourouma bicolore, Symphonia globulifera, Tachigali versicolor, Tapirira guianensis, and Virola sebifera. The files included in this data package are in .csv and .pdf format, with two Excel files containing additional metadata.
54 ENVIRONMENTAL SCIENCES↗
Smart Charging for Electric Ride-Hailing Vehicles using Renewables: A San Francisco Case Study
Charging large fleets of electric ride-hailing vehicles (ERVs) is a complex matter that could serve different objectives: lower carbon dioxide emissions, lower monetary expenditures, or maximize solar photovoltaics (PV) energy consumption. Currently, it is unclear how each of those objectives could impact the business and performance of a ride-hailing fleet. In order to fill this gap, this article employs a dynamic transportation model: a smart charging simulation that combines agent-based, discrete-event, and system dynamic modelling by comparing the above-mentioned objectives in separate scenarios. The results show that each scenario successfully manages to shift between 34% and 87% of all load to hours of the day when the objectives of those scenarios are met. Therefore, in comparison to the baseline, smart charging can save between 5% and 26% of monthly emissions and between 4% and 57% of monthly expenditures. The solar PV scenario, however, results in the highest savings, while ensuring profitable economics via net metering in the short- as well as long term. Finally, the sensitivity analysis points to important trade-offs between several fleet performance metrics. The article concludes by giving business and policy recommendations for maximising the economic, energy and environmental efficiency of large ERV fleets.
ADVANCED PROPULSION SYSTEMS,SOLAR ENERGY↗
Mesocarnivore Surveys on Lawrence Livermore National Laboratory Site 300 Alameda and San Joaquin Counties, California
Lawrence Livermore National Laboratory (LLNL), operated under cooperative agreement between the University of California and the U. S. Department of Energy, administers and operates an approximately 11 mi2 (2$ km2) test site in the remote hills at the northern end of the South Coast Ranges of Central California. Known as Site 300, this expanse of rolling hills and canyons supports a diverse array of grassland communities typical of lowland central California. The facility serves a variety of functions related to testing non-nuclear explosives, lasers, and weapons subsystems. The primary purpose of this project was to determine the presence of any mesocamivores on Site 300 that use the property for foraging, denning, and other related activities. The surveys occurred from mid-September to mid-October, 2002.
54 ENVIRONMENTAL SCIENCES↗
San Manuel Band of Mission Indians Tribal Utility Development Project
First steps in assessing the viability of the development of a utility, complete the initial legal, financial, and regulatory steps necessary to develop and implement a sustainable tribally-owned energy utility organization.
29 ENERGY PLANNING, POLICY, AND ECONOMY↗
Large Game Movement between Los Alamos National Laboratory and Pueblo de San Ildefonso
Movement by wildlife is a fundamental process that allows for the distribution of animal populations. The level and scale of movement varies by species, time of year, and whether long-distance migration plays a role in a species’ life history. Many species do not have regular migration patterns, but still have movement patterns essential to their survival. Changes in the environment such as wildfires, drought, and anthropogenic activities have the potential to influence the movements of animals.
99 GENERAL AND MISCELLANEOUS↗
Wetland/Aquatic Resources Delineation Sitewide Environmental Impact Statement, Lawrence Livermore National Laboratory Facilities, Alameda and San Joaquin Counties, California
Nomad Ecology, LLC (Nomad) prepared this Wetland/Aquatic Resources Delineation at the request of Lawrence Livermore National Laboratory (LLNL) for their Sitewide Environmental Impact Statement (SWEIS). This Wetland/Aquatic Resource Delineations presents the results for three LLNL locations: LLNL Livermore (Site 200), LLNL Experimental Test Site (Site 300), and the Arroyo Mocho Pumping Station (Arroyo Mocho). Table 1 summarizes each study area and lists the Assessor’s Parcel Numbers (APNs).
54 ENVIRONMENTAL SCIENCES↗
Sitewide Environmental Impact Statement Site 300 and Arroyo Mocho Lawrence Livermore National Laboratory Alameda and San Joaquin Counties, California (Mid-Term Report)
At the request of Lawrence Livermore National Security (LLNS), Nomad Ecology (Nomad) conducted sensitive botanical resource surveys, and vegetation mapping and classification of the 7,000-acre Lawrence Livermore National Laboratory (LLNL) Experimental Test Site (Site 300) and 17 acres surrounding the Arroyo Mocho pumping station and the access road to the pumping station (Arroyo Mocho). In addition to surveying for sensitive botanical resources, Nomad also compiled existing rare plant and vegetation data provided by LLNL from past monitoring and environmental impact evaluations. The results of these efforts will provide supporting information for a Site-wide Environmental Impact Statement (SWEIS). These surveys were conducted during the months of April – June, and August 2020. Rare plant surveys were scheduled for February and March 2020; however, February surveys were not initiated because the contract for this work was not finalized, and March surveys were cut short due to the timing of the Covid-19 shelter in place. February and March rare plant surveys are scheduled for 2021; therefore, the rare plant survey results in this report should be considered incomplete until the 2021 surveys are conducted. A total of 10 special status plant species were recorded within Site 300 and Arroyo Mocho. Of these 10, three were not previously recorded within the study areas, and include Hospital Canyon larkspur (Delphinium californicum subsp. interius), Jepson’s woolly sunflower (Eriophyllum jepsonii), and Michael’s rein orchid (Piperia michaelii), which all occur at Arroyo Mocho. Special status plant species known from these two sites total 23 rare plant occurrences (populations), which represent an estimated 50,929 rare plant individuals. This total of all special status plant species breaks down to one occurrence of a federally and/or state listed plant species (98 individuals), six occurrences of California Rare Plant Rank (CRPR) 1 & 2 species (49,010 individuals), and 16 occurrences of CRPR 3 & 4 species (1,821 individuals). A total of 35 vegetation communities were mapped at Site 300, of which 20 are considered Sensitive Natural Communities. A total of nine vegetation communities were mapped at Arroyo Mocho, of which two are considered Sensitive Natural Communities.
54 ENVIRONMENTAL SCIENCES↗
Final Site 300 Sensitive Botanical Resource Report for the Sitewide Environmental Impact Statement, Lawrence Livermore National Laboratory, Alameda and San Joaquin Counties, California
At the request of Lawrence Livermore National Security (LLNS), Nomad Ecology (Nomad) conducted sensitive botanical resource surveys, and vegetation mapping and classification of the 7,000-acre Lawrence Livermore National Laboratory (LLNL) Experimental Test Site (Site 300). In addition to surveying for sensitive botanical resources, Nomad also compiled existing rare plant and vegetation data provided by LLNL from past monitoring and environmental impact evaluations. The results of these efforts will provide supporting information for a Site-wide Environmental Impact Statement (SWEIS). These surveys were conducted during the months of April-June, and August 2020, and February and March 2021. Rare plant surveys were originally scheduled for February and March 2020; however, February surveys were not initiated because the contract for this work was not finalized, and March surveys were cut short due to the timing of the Covid-19 shelter in place. Therefore, February and March rare plant surveys were conducted in 2021. A total of seven special status plant species were recorded within Site 300. Special status plant species known from the site total 26 rare plant occurrences (populations), which represent an estimated 14,077 rare plant individuals. This total of all special status plant species breaks down to one occurrence of a federally and/or state listed plant species (98 individuals), five occurrences of California Rare Plant Rank (CRPR) 1 & 2 species (11,553 individuals), and 20 occurrences of CRPR 3 & 4 species (2,426 individuals). A total of 35 vegetation communities were mapped at Site 300, of which 20 are considered Sensitive Natural Communities.
54 ENVIRONMENTAL SCIENCES↗
CO2 Sweep Based on Geochemical, and Reservoir Characterization of the Residual Oil Zone of Hess's Seminole San Andres Unit (Final Report)
The study of the ROZ (residual oil zone) versus the MPZ (main pay zone) of the Seminole Field provided a unique insight into the nature of ROZ. This is because we had access to an order of magnitude of core available in other fields. We were also able to use an extensive petrophysical data base with one-foot sampling interval made available by the operator. We also obtained an extensive and unique data base containing the entire production history for the field at full resolution. The data set also includes a unique complete, highly-granular information on volumes of CO2 injection and CO2 production. We created a unique high-resolution model of the reservoir. This is the first such model that has been created. Using this very high-resolution data base we were able to make high resolution, multiphase fluid flow simulations. These fluid flow simulations have enabled our team to evaluate CO2 sweep in the ROZ in comparison with the MPZ.
01 COAL, LIGNITE, AND PEAT↗
Assessment of San Onofre Concrete Susceptibility Against Irradiation Damage
The work performed under this contract covers the characterization of unirradiated concrete specimens cored from the walls of the steam generator room of the SONGS Unit 2, currently under decommission. This report documents the extensive set of characterization conducted at the Oak Ridge National Laboratory, at the University of Tennessee, Knoxville, at the Ohio State University, and at ALG Global. The susceptibility of irradiation-induced damage in concrete is governed by the exposure level (fast neutron fluence > 10 19 n.cm -2 at E > 0.1 MeV) and the mineralogy of the aggregates (high quartz content and chemical heterogeneity of the assemblage). Both conditions are met for the SONGS concrete biological shield. Hence, harvesting in-service irradiated concrete from the SONGS Unit 2 or 3 biological shield is currently an unparalleled opportunity to study the flux effects of neutron irradiation.
36 MATERIALS SCIENCE↗