Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “STANDARDS”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,315 records · Page 73

Non-stationary precipitation design standards for stormwater infrastructure modernization at USAF installations

The resilience of defense infrastructure systems to a changing climate is critical for national security. Climate induced recurrent flooding is already impacting over 20 U.S. Air Force installations, underscoring the urgency of revisiting precipitation standards and stormwater infrastructure design. Despite growing scientific knowledge and an expanding set of tools for updating outdated precipitation standards based on the assumption of climate stationarity, the adoption of climate informed analyses remain limited in practice. This study utilizes an existing framework to update Intensity (or Depth)-Duration-Frequency (DDF) curves using an ensemble of future climate projections. Change factors in precipitation estimates are derived and applied to six USAF installations across the U.S. The analysis is further extended to evaluate the implications of climate-informed DDFs on stormwater infrastructure performance and flood analysis at Tyndall AFB. Results indicate that the current design precipitation estimates are likely to become obsolete in all six USAF bases by the end of the century. The wide range of change factors across 32 GCM ensembles highlights the need to integrate uncertainty and evolving scientific data into infrastructure planning. The study also finds that the impacts of a changing climate vary spatially and temporally, emphasizing the value of localized analysis for infrastructure decision-making. The work advances ongoing DoD and societal efforts to implement adaptation strategies aimed at enhancing infrastructure resilience.

Intensity-duration-frequency curves↗

Adaptation of methodology to select structural alternatives of one-way slab in residential building to the guidelines of the European Committee for Standardization (CEN/TC 350)

The European Committee for Standardization (CEN) through its Technical Committee CEN/TC-350 is developing a series of standards for assessing the building sustainability, at both product and building levels. The practical application of the selection (decision making) of structural alternatives made by one-way slabs leads to an intermediate level between the product and the building. Thus the present study addresses this problem of decision making, following the CEN guidelines and incorporating relevant aspects of architectural design into residential construction. A life cycle assessment (LCA) is developed in order to obtain valid information for the decision making process (the LCA was developed applying CML methodology although Ecoindicator99 was used in order to facilitate the comparison of the values); this information (the carbon footprint values) is contrasted with other databases and with the information from the Environmental Product Declaration (EPD) of one of the lightening materials (expanded polystyrene), in order to validate the results. Solutions of different column disposition and geometries are evaluated in the three pillars of sustainable construction on residential construction: social, economic and environmental. The quantitative analysis of the variables used in this study enables and facilitates an objective comparison in the design stage by a responsible technician; the application of the proposed methodology reduces the possible solutions to be evaluated by the expert to 12.22% of the options in the case of low values of the column index and to 26.67% for the highest values. - Highlights: • Methodology for selection of structural alternatives in buildings with one-way slabs • Adapted to CEN guidelines (CEN/TC-350) for assessing the building sustainability • LCA is developed in order to obtain valid information for the decision making process. • Results validated comparing carbon footprint, databases and Env. Product Declarations • The proposal reduces the solutions to be evaluated to between 12.22 and 26.67%.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Building energy simulation in real time through an open standard interface

Building energy models (BEMs) are typically used for design and code compliance for new buildings and in the renovation of existing buildings to predict energy use. We present the increasing adoption of BEM as standard practice in the building industry presents an opportunity to extend the use of BEMs into construction, commissioning and operation. In 2009, the authors developed a real-time simulation framework to execute an EnergyPlus model in real time to improve building operation. This paper reports an enhancement of that real-time energy simulation framework. The previous version only works with software tools that implement the custom co-simulation interface of the Building Controls Virtual Test Bed (BCVTB), such as EnergyPlus, Dymola and TRNSYS. The new version uses an open standard interface, the Functional Mockup Interface (FMI), to provide a generic interface to any application that supports the FMI protocol. In addition, the new version utilizes the Simple Measurement and Actuation Profile (sMAP) tool as the data acquisition system to acquire, store and present data. Lastly, this paper introduces the updated architecture of the real-time simulation framework using FMI and presents proof-of-concept demonstration results which validate the new framework.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Development of a frequency regulation duty-cycle for standardized energy storage performance testing

The US DOE Protocol for uniformly measuring and expressing the performance of energy storage systems, first developed in 2012 through inclusive working group activities, provides standardized methodologies for evaluating an energy storage system’s ability to supply specific services to electrical grids. This article elaborates on the data and decisions behind the duty-cycle used for frequency regulation in this protocol. Analysis of a year of publicly available frequency regulation control signal data from a utility was considered in developing the representative signal for this use case. Moreover, this showed that signal standard deviation can be used as a metric for aggressiveness or rigor. From these data, we select representative 2 h long signals that exhibit nearly all of dynamics of actual usage under two distinct regimens, one for average use and the other for highly aggressive use. Our results were combined into a 24-h duty-cycle comprised of average and aggressive segments. The benefits and drawbacks of the selected duty-cycle are discussed along with its potential implications to the energy storage industry.

25 ENERGY STORAGE↗

Detection of low Temperature heat release (LTHR) in the standard Cooperative Fuel Research (CFR) engine in both SI and HCCI combustion modes

To this date, extensive research has been conducted to understand the low-temperature auto-ignition chemistry of gasoline. The detection of low-temperature chemical reactions under Spark Ignition (SI) combustion cannot be detected, as they are hidden by the flame propagation. Alternatively, Homogeneous Charge Compression Ignition (HCCI) combustion has a two-stage combustion involving low and high-temperature heat release (LTHR and HTHR respectively). Both Knocking SI and HCCI combustion involve auto-ignition and are governed by fuel characteristics and the pressure-temperature (P-T) history. Therefore, HCCI combustion might provide an alternative to understand the knocking behavior and LTHR in modern SI engines. A standard Cooperative Fuel Research (CFR) engine was operated at lean HCCI conditions (lambda 3), as well as SI conditions at stoichiometry. For SI combustion, the CFR engine was operated with RON-like conditions, but at late spark timing to induce LTHR prior to flame propagation. Three RON 90 binary fuel blends were investigated, being composed of n-heptane with isooctane, toluene, or ethanol. This work demonstrated that the CFR engine under stoichiometric SI with late spark timing and HCCI combustion mode can help to detect LTHR which is not possible in the standard RON test. The intake pressure and temperature sweeps showed similar effects on LTHR for both combustion modes. The linking of auto-ignition behavior of SI and HCCI was dependent primarily on intake valve closing (IVC) conditions. In conclusion, the high exhaust temperature in SI lead to high IVC temperatures. In order to match the IVC temperatures and to overlap the P-T trajectories, the intake temperature for HCCI was increased.

33 ADVANCED PROPULSION SYSTEMS↗

Randomized Trial of Pentoxifylline and Vitamin E vs Standard Follow-up After Breast Irradiation to Prevent Breast Fibrosis, Evaluated by Tissue Compliance Meter

Purpose: To conduct a randomized clinical trial to determine whether the combination of pentoxifylline (PTX) and vitamin E given for 6 months after breast/chest wall irradiation effectively prevents radiation-induced fibrosis (RIF). Methods and Materials: Fifty-three breast cancer patients with localized disease were enrolled and randomized to treatment with oral PTX 400 mg 3 times daily and oral vitamin E 400 IU daily for 6 months after radiation (n=26), or standard follow up (n=27). Tissue compliance meter (TCM) measurements were obtained at 18 months to compare tissue compliance in the irradiated and untreated breast/chest wall in treated subjects and controls. Measurements were obtained at 2 mirror image sites on each breast/chest wall, and the average difference in tissue compliance was scored. Differences in TCM measurements were compared using a t test. Subjects were followed a minimum of 2 years for local recurrence, disease-free survival, and overall survival. Results: The mean difference in TCM measurements in the 2 groups was 0.88 mm, median of 1.00 mm (treated) and 2.10 mm, median of 2.4 mm (untreated). The difference between the 2 groups was significant (P=.0478). Overall survival (100% treated, 90.6% controls at 5 years) and disease-free survival (96.2% treated, 86.8% controls at 5 years) were not significantly different in the 2 groups. Conclusions: This study of postirradiation breast cancer patients treated with PTX/vitamin E or standard follow-up indicated a significant difference in radiation-induced fibrosis as measured by TCM. There was no observed impact on local control or survival within the first 2 years of follow-up. The treatment was safe and well tolerated. Pentoxifylline/vitamin E may be clinically useful in preventing fibrosis after radiation in high-risk patients.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

[{sup 18}F]FDG-PET Standard Uptake Value as a Metabolic Predictor of Bone Marrow Response to Radiation: Impact on Acute and Late Hematological Toxicity in Cervical Cancer Patients Treated With Chemoradiation Therapy

Purpose: To quantify the relationship between bone marrow (BM) response to radiation and radiation dose by using {sup 18}F-labeled fluorodeoxyglucose positron emission tomography [{sup 18}F]FDG-PET standard uptake values (SUV) and to correlate these findings with hematological toxicity (HT) in cervical cancer (CC) patients treated with chemoradiation therapy (CRT). Methods and Materials: Seventeen women with a diagnosis of CC were treated with standard doses of CRT. All patients underwent pre- and post-therapy [{sup 18}F]FDG-PET/computed tomography (CT). Hemograms were obtained before and during treatment and 3 months after treatment and at last follow-up. Pelvic bone was autosegmented as total bone marrow (BM{sub TOT}). Active bone marrow (BM{sub ACT}) was contoured based on SUV greater than the mean SUV of BM{sub TOT}. The volumes (V) of each region receiving 10, 20, 30, and 40 Gy (V{sub 10}, V{sub 20}, V{sub 30}, and V{sub 40}, respectively) were calculated. Metabolic volume histograms and voxel SUV map response graphs were created. Relative changes in SUV before and after therapy were calculated by separating SUV voxels into radiation therapy dose ranges of 5 Gy. The relationships among SUV decrease, radiation dose, and HT were investigated using multiple regression models. Results: Mean relative pre-post-therapy SUV reductions in BM{sub TOT} and BM{sub ACT} were 27% and 38%, respectively. BM{sub ACT} volume was significantly reduced after treatment (from 651.5 to 231.6 cm{sup 3}, respectively; P<.0001). BM{sub ACT} V{sub 30} was significantly correlated with a reduction in BM{sub ACT} SUV (R{sup 2}, 0.14; P<.001). The reduction in BM{sub ACT} SUV significantly correlated with reduction in white blood cells (WBCs) at 3 months post-treatment (R{sup 2}, 0.27; P=.04) and at last follow-up (R{sup 2}, 0.25; P=.04). Different dosimetric parameters of BM{sub TOT} and BM{sub ACT} correlated with long-term hematological outcome. Conclusions: The volumes of BM{sub TOT} and BM{sub ACT} that are exposed to even relatively low doses of radiation are associated with a decrease in WBC counts following CRT. The loss in proliferative BM SUV uptake translates into low WBC nadirs after treatment. These results suggest the potential of intensity modulated radiation therapy to spare BM{sub TOT} to reduce long-term hematological toxicity.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Clinical Outcomes Among Children With Standard-Risk Medulloblastoma Treated With Proton and Photon Radiation Therapy: A Comparison of Disease Control and Overall Survival

Purpose: The purpose of this study was to compare long-term disease control and overall survival between children treated with proton and photon radiation therapy (RT) for standard-risk medulloblastoma. Methods and Materials: This multi-institution cohort study includes 88 children treated with chemotherapy and proton (n=45) or photon (n=43) RT between 2000 and 2009. Overall survival (OS), recurrence-free survival (RFS), and patterns of failure were compared between the 2 cohorts. Results: Median (range) age was 6 years old at diagnosis (3-21 years) for proton patients versus 8 years (3-19 years) for photon patients (P=.011). Cohorts were similar with respect to sex, histology, extent of surgical resection, craniospinal irradiation (CSI) RT dose, total RT dose, whether the RT boost was delivered to the posterior fossa (PF) or tumor bed (TB), time from surgery to RT start, or total duration of RT. RT consisted of a median (range) CSI dose of 23.4 Gy (18-27 Gy) and a boost of 30.6 Gy (27-37.8 Gy). Median follow-up time is 6.2 years (95% confidence interval [CI]: 5.1-6.6 years) for proton patients versus 7.0 years (95% CI: 5.8-8.9 years) for photon patients. There was no significant difference in RFS or OS between patients treated with proton versus photon RT; 6-year RFS was 78.8% versus 76.5% (P=.948) and 6-year OS was 82.0% versus 87.6%, respectively (P=.285). On multivariate analysis, there was a trend for longer RFS with females (P=.058) and higher CSI dose (P=.096) and for longer OS with females (P=.093). Patterns of failure were similar between the 2 cohorts (P=.908). Conclusions: Disease control with proton and photon radiation therapy appears equivalent for standard risk medulloblastoma.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

On the utility of GPU accelerated high-order methods for unsteady flow simulations: A comparison with industry-standard tools

First- and second-order accurate numerical methods, implemented for CPUs, underpin the majority of industrial CFD solvers. Whilst this technology has proven very successful at solving steady-state problems via a Reynolds Averaged Navier–Stokes approach, its utility for undertaking scale-resolving simulations of unsteady flows is less clear. High-order methods for unstructured grids and GPU accelerators have been proposed as an enabling technology for unsteady scale-resolving simulations of flow over complex geometries. In this study we systematically compare accuracy and cost of the high-order Flux Reconstruction solver PyFR running on GPUs and the industry-standard solver STAR-CCM+ running on CPUs when applied to a range of unsteady flow problems. Specifically, we perform comparisons of accuracy and cost for isentropic vortex advection (EV), decay of the Taylor–Green vortex (TGV), turbulent flow over a circular cylinder, and turbulent flow over an SD7003 aerofoil. We consider two configurations of STAR-CCM+: a second-order configuration, and a third-order configuration, where the latter was recommended by CD-adapco for more effective computation of unsteady flow problems. Results from both PyFR and STAR-CCM+ demonstrate that third-order schemes can be more accurate than second-order schemes for a given cost e.g. going from second- to third-order, the PyFR simulations of the EV and TGV achieve 75× and 3× error reduction respectively for the same or reduced cost, and STAR-CCM+ simulations of the cylinder recovered wake statistics significantly more accurately for only twice the cost. Moreover, advancing to higher-order schemes on GPUs with PyFR was found to offer even further accuracy vs. cost benefits relative to industry-standard tools.

97 MATHEMATICS AND COMPUTING↗

Standard methods for heat capacity measurements on a Quantum Design Physical Property Measurement System

The commercial availability of the Physical Property Measurement System (PPMS) by Quantum Design has significantly increased access to heat capacity measurements on a wide variety of materials. Although the PPMS can routinely measure the heat capacities of thermally conducting materials with high accuracy, specialized sample mounting techniques must be used for insulating powders, and the analysis of first order transitions also requires non-standard methods. The concern is that many users are not aware of these constraints when measuring the heat capacity of a diverse array of materials, and therefore, the heat capacity data reported in the literature can be unreliable. In this paper, we provide an extensive and critical review of the heat capacity data reported in the literature measured using the Quantum Design PPMS. The purpose is to provide a de facto standard for sample mounting and data analysis methods suitable for the reporting of accurate thermodynamic data.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Creating high-precision reference gas standards of 85Kr for groundwater age-dating

Absolute gas counting (AGC) was applied to two gas blends of 85Kr in argon-methane (P10) counting gas to establish a high-precision specific activity (Bq/cm3) reference value for characterizing 85Kr detection efficiency for groundwater age dating measurements. The AGC or length-compensated technique has been utilized by the metrology community for decades and is an accepted method for developing radioactive gas standards. The AGC capability at Pacific Northwest National Laboratory (PNNL) uses a set of nine unequal-length proportional counters with precisely-measured internal volumes, and a gas loading system with high-precision pressure and temperature sensors. A series of AGC measurements were collected at multiple pressures to determine the inverse pressure relationship (1/P) for 85Kr and define a wall-effect correction that accounts for events decaying into the detector wall and not depositing sufficient energy in the gas to be detected. In addition to the wall-effect, two additional corrections were evaluated and are discussed in detail. Specifically, the threshold effect which accounts for events deposited below the analysis threshold and a detection efficiency as a function of detector volume effect that was observed during analysis. A robust uncertainty model was developed using the Guide to the expression of Uncertainty in Measurements (GUM) approach. The combination of carefully scrutinized correction factors, precise measurements of pressure, temperature and detector volume, and robust counting statistics resulted in the determination of high-precision specific activity values with 0.50% or less total combined uncertainty for two Kr-in-P10 reference gas standards (KP10) that will enable new groundwater age-dating measurements at PNNL.

Kr-85↗

Synthesis and characterization of LTA nanozeolite using barley husk silica: Mercury removal from standard and real solutions

Highlights: ► Silica extraction from barley husk with high purity for the synthesis of A nanozeolite. ► Free template A nanozeolite synthesized via new source of silica at low temperature. ► Optimization of SiO{sub 2}/Al{sub 2}O{sub 3}, Na{sub 2}O/SiO{sub 2} ratios, temperature and time of the synthesis. ► Utilizing of synthesized A nanozeolite for mercury removal from aqueous solutions. ► Mercury removal at optimized pH, contact time and adsorbent dose from real solution. - Abstract: In this study, synthesized Lined Type A (LTA) nanozeolite from barley husk silica (BHS) was used for mercury removal from standard and real aqueous solutions. The BHS in amorphous phase with 80% purity was extracted from barley husk ash (BHA), and used effectively as a new source of silica for the synthesis of NaA nanozeolite. The NaA nanocrystal in pure phase has been synthesized at low temperature, without adding any organic additives. The effects of heating time, reaction temperature, SiO{sub 2}/Al{sub 2}O{sub 3}, and Na{sub 2}O/SiO{sub 2} mole ratios on the crystallization of NaA nanozeolite were studied. The adsorption capacity of mercury (II) was studied as a function of pH, contact time, and amount of adsorbent. The crystallization of NaA nanozeolite from BHS was characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), Brunauer–Emmett–Teller (BET), and FTIR techniques. Moreover, concentration of Hg{sup 2+} ions in the aqueous solutions was analyzed by hydride generation atomic absorption spectroscopy method (HG-AAS). The standard and real samples analysis showed that NaA nanozeolite is capable of Hg{sup 2+} ions removal from the aqueous solutions. Efficiency of mercury (II) adsorption from real solutions onto the nano-sized NaA zeolite was 98%.

36 MATERIALS SCIENCE↗

Codes and standards for ceramic composite core materials for High Temperature Reactor applications

Fiber-reinforced ceramic matrix composites are attractive for high-temperature nuclear applications due to excellent thermal and mechanical properties as well as reasonable-to-outstanding radiation resistance. Over the past 20 years, the use of ceramic matrix composite applications expanded to many commercial non-nuclear industries as fabrication and application of the technologies mature. The ASME Boiler Pressure Vessel Code, under Section III Division 5, provides the design and construction rules for High Temperature Reactor components. It published the first rules for ceramic matrix composites to be used for reactor core components. The rules lay out the quality requirements together with the design and materials criteria for the use and application of silicon carbide- and carbon-based matrix material technologies. As with the established graphite rules, the ceramic composite material rules are structured in Subsection HH (from Section III), that addresses the criteria for class SN nonmetallic core components. The code rules rely heavily on the development and publication of standards for composite specification, classification, and testing of mechanical, thermal, and other properties. These test methods are developed in ASTM Committee C28 on Advanced Ceramics, with a current focus on ceramic composite tubes. This article describes the detail of the composites code, the design methodology and similarities to the graphite code, the guidance for the development of specifications for ceramic composites (for nuclear applications) including recent standard developments, and it mentions the next steps to support licensing aspects by validating the code with benchmarking data.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗

Search for a standard model-like Higgs boson in the mass range between 70 and 110 GeV in the diphoton final state in proton-proton collisions at $\sqrt{s} = 13$ TeV

The results of a search for a standard model-like Higgs boson decaying into two photons in the mass range between 70 and 110 GeV are presented. The analysis uses the data set collected by the CMS experiment in proton-proton collisions at $\sqrt{s} = 13$ TeV corresponding to integrated luminosities of 36.3 fb -1 , 41.5 fb -1 and 54.4 fb -1 during the 2016, 2017, and 2018 LHC running periods, respectively. No significant excess over the background expectation is observed and 95% confidence level upper limits are set on the product of the cross section and branching fraction for decays of an additional Higgs boson into two photons. The maximum deviation with respect to the background is seen for a mass hypothesis of 95.4 GeV with a local (global) significance of 2.9 (1.3) standard deviations. The observed upper limit ranges from 15 to 73 fb.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Search for bottom quark associated production of the standard model Higgs boson in final states with leptons in proton-proton collisions at $\sqrt{s}$ =13 TeV

This Letter presents the first search for bottom quark associated production of the standard model Higgs boson, in final states with leptons. Higgs boson decays to pairs of tau leptons and pairs of leptonically decaying W bosons are considered. The search is performed using data collected from 2016 to 2018 by the CMS experiment in proton-proton collisions at a centre-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 138 fb -1 . Upper limits at the 95% confidence level are placed on the signal strength for Higgs boson production in association with bottom quarks; the observed (expected) upper limit is 3.7 (6.1) times the standard model prediction

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

SMEFT ATLAS: The landscape beyond the Standard Model

The Standard Model Effective Field Theory (SMEFT) based on the unbroken gauge group SU(3) 𝐶 ⊗SU(2) 𝐿 ⊗U(1) 𝑌 and containing only particles of the Standard Model (SM) has developed in the last decade to a mature field. It is the framework to be used in the energy gap from scales sufficiently higher than the electroweak scale up to the lowest energy scale at which new particles show up. We summarize the present status of this theory with a particular emphasize on its role in the indirect search for new physics (NP). While flavour physics of both quarks and leptons is the main topic of our review, we also discuss electric dipole moments, anomalous magnetic moments (𝑔−2) 𝜇,𝑒 , 𝑍-pole observables, Higgs observables and high-𝑝𝑇 scattering processes within the SMEFT. We group the observables into ten classes and list for each class the most relevant operators and the corresponding renormalization group equations (RGEs). We exhibit the correlations between different classes implied both by the operator mixing and the SU(2) 𝐿 gauge symmetry. Our main goal is to provide an insight into the complicated operator structure of this framework which hopefully will facilitate the identification of valid ultraviolet completions behind possible anomalies observed in future data. Numerous colourful charts, and 85 tables, while representing rather complicated RG evolution from the NP scale down to the electroweak scale, beautify the involved SMEFT landscape. Over 1000 references to the literature underline the importance and the popularity of this field. We discuss both top-down and bottom-up approaches as well as their interplay. This allows us eventually to present an atlas of different landscapes beyond the SM that includes heavy gauge bosons and scalars, vector-like quarks and leptons and leptoquarks.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Standardization of the Distributed Ledger Technology cybersecurity stack for power and energy applications

The global trend towards the integration of distributed energy resources is opening the doors to advanced, complex, and distributedmarketplaces. Such advanced ecosystems, where utility-owned and non utility-owned assets can contribute towards grid operations,generally require distributed communication and grid architectures, which can be supported by Distributed Ledger Technologies(DLTs). However, the potential of DLTs for long-term scalable solutions in operational technology applications has not been fullyutilized, partly due to the lack of standardization across and between different DLTs, as well as other supporting building blocks(e.g., communication protocols). This paper attempts to address this gap by proposing a DLT cybersecurity stack specificallydesigned for researchers, DLT technology developers, and end users (such as utilities). The DLT cybersecurity stack has beennotionally mapped to related cybersecurity components, namely: the Open Systems Interconnection (OSI) model, the TransmissionControl Protocol/Internet Protocol (TCP/IP) suite, and existing Smart Grid architecture frameworks. In addition, the paper discussesseveral cybersecurity implications, and demonstrates the potential uses of the DLT stack through multiple power and energy usecases. It is important to note that the stack can be also applied to the DLT use cases that are outside the power and energy domain.This work has been performed by the Cybersecurity Task Force under the IEEE P2418.5 Blockchain for Energy Standard workinggroup that is stationed under the IEEE Power and Energy Society’s Smart Buildings, Loads, and Customer Systems (SBLC)technical committee.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Comprehensive Chemical Characterization of Hydrocarbons in NIST Standard Reference Material 2779 Gulf of Mexico Crude Oil

Comprehensive chemical information is needed to understand the environmental fate and impact of hydrocarbons released during oil spills. However, chemical information remains incomplete because of the limitations of current analytical techniques and the inherent chemical complexity of crude oils. In this study, gas chromatography (GC)-amenable C 9 -C 33 hydrocarbons were comprehensively characterized from the National Institute of Standards and Technology Standard Reference Material (NIST SRM) 2779 Gulf of Mexico crude oil by GC coupled to vacuum ultraviolet photoionization mass spectrometry (GC/VUV-MS), with a mass balance of 68 ± 22%. This technique overcomes one important limitation faced by traditional GC and even comprehensive 2D gas chromatography (GC×GC): the necessity for individual compounds to be chromatographically resolved from one another in order to be characterized. VUV photoionization minimizes fragmentation of the molecular ions, facilitating the characterization of the observed hydrocarbons as a function of molecular weight (carbon number, N C ), structure (number of double bond equivalents, N DBE ), and mass fraction (mg kg -1 ), which represent important metrics for understanding their fate and environmental impacts. Linear alkanes (8 ± 1%), bran ched alkanes (11 ± 2%), and cycloalkanes (37 ± 12%) dominated the mass with the largest contribution from cycloalkanes containing one or two rings and one or more alkyl side chains (27 ± 9%). Linearity and good agreement with previous work for a subset of >100 components and for the sum of compound classes provided confidence in our measurements and represents the first independent assessment of our analytical approach and calibration methodology. Another crude oil collected from the Marlin platform (35 km northeast of the Macondo well) was shown to be chemically identical within experimental errors to NIST SRM 2779, demonstrating that Marlin crude is an appropriate surrogate oil for researchers conducting laboratory research into impacts of the DeepWater Horizon disaster.

02 PETROLEUM↗