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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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At least 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
DOE OSTI2014

Communication: Ro-vibrational control of chemical reactivity in H+CH{sub 4}→ H{sub 2}+CH{sub 3} : Full-dimensional quantum dynamics calculations and a sudden model

The mode-selective chemistry of the title reaction is studied by full-dimensional quantum dynamics simulation on an accurate ab initio potential energy surface for vanishing total angular momentum. Using a rigorous transition state based approach and multi-configurational time-dependent Hartree wave packet propagation, initial state-selected reaction probabilities for many ro-vibrational states of methane are calculated. The theoretical results are compared with experimental trends seen in reactions of methane. An intuitive interpretation of the ro-vibrational control of the chemical reactivity provided by a sudden model based on the quantum transition state concept is discussed.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2012

HIGH-RESOLUTION NEAR-INFRARED SPECTROSCOPY OF HD 100546. I. ANALYSIS OF ASYMMETRIC RO-VIBRATIONAL OH EMISSION LINES

We present observations of ro-vibrational OH and CO emission from the Herbig Be star HD 100546. The emission from both molecules arises from the inner region of the disk extending from approximately 13 AU from the central star. The velocity profiles of the OH lines are narrower than the velocity profile of the [O I] {lambda}6300 line, indicating that the OH in the disk is not cospatial with the O I. This suggests that the inner optically thin region of the disk is largely devoid of molecular gas. Unlike the ro-vibrational CO emission lines, the OH lines are highly asymmetric. We show that the average CO and average OH line profiles can be fit with a model of a disk comprised of an eccentric inner wall and a circular outer disk. In this model, the vast majority of the OH flux (75%) originates from the inner wall, while the vast majority of the CO flux (65%) originates on the surface of the disk at radii greater than 13 AU. Eccentric inner disks are predicted by hydrodynamic simulations of circumstellar disks containing an embedded giant planet. We discuss the implications of such a disk geometry in light of models of planet-disk tidal interactions and propose alternative explanations for the origin of the asymmetry.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2015

SU-E-T-138: Automated Chart Review Module Including Cross-Vendor Data Transfer Verification Developed for IHE-RO Initiative

Purpose: To follow the Integrating Healthcare Enterprise - Radiation Oncology (IHE-RO) initiative of proper cross-vendor technology integration, an automated chart checker (ACC) was developed. ACC compares extracted data from an approved patient plan in the Eclipse treatment planning system (TPS) against data existing in the Mosaiq treatment management system (TMS). ACC automatically analyzes these parameters using built-in quality checklists to provide further aid in chart review. Methods: Eclipse TPS data are obtained using Eclipse scripting API (ESAPI) while Mosaiq TMS data are obtained from a radiotherapy-treatment-planning (RTP) file. Using this information, ACC identifies TPS-TMS discrepancies in 18 primary beam parameters including MU, energy, jaw positions, gantry angle, table angle, accessories, and bolus for up to 31 beams. Next, approximately 40 items from traditional quality checklists are evaluated such as prescription consistency, DRR graticule placement, plan approval status, global max dose, and dose tracking coefficients. Parameters were artificially modified to determine if ACC would detect an error in data transfer and to test each component of quality checklists. Results: Using ESAPI scripting and RTP file-processing, ACC was able to properly aggregate data from TPS and TMS for up to 31 beams. Errors were artificially introduced into each plan parameter, and ACC was able to successfully detect all of them within seconds. Next, ACC was able to successfully detect mistakes in the chart by identifying deviations with its quality checklists, within seconds. Conclusion: ACC effectively addresses the potential issue of faulty cross-vendor data transfer, as described by IHE-RO. In addition, ACC was also able to detect deviations from its built-in quality checklists. ACC is already an invaluable tool for efficient and standardized chart review and will continue to improve as its incorporated checklists become more comprehensive.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2025

Techno-economic assessment of distributed wellhead RO water treatment for nitrate removal and salinity reduction: A field study in small disadvantaged communities

Techno-economic analysis of distributed wellhead water treatment and desalination (DWTD) systems was carried out based on a three-year field study in three small, disadvantaged communities (DACs) to evaluate the reliability and affordability of upgrading their impaired well water. The local water supplies of the three study DACs, located in Salinas Valley, California, were contaminated with nitrate at levels (~ 12–87 mg/L NO$^{-}_{3}$ - N) ) above the California maximum contaminant level (MCL) of 10 mg/L NO$^{-}_{3}$ - N , and had elevated water salinity (~600–1,600 mg/L total dissolved solids(TDS)) above its secondary MCL (SMCL) of 500 mg/L TDS. Well water nitrate removal and salinity reduction were accomplished via reverse osmosis (RO) based DWTD systems that operated autonomously, supported by remote monitoring and supervisory cyberinfrastructure. Reliable DWTD operation provided treated water quality, with respect to nitrate and salinity, in the range of 0.5–6.3 mg/L NO$^{-}_{3}$ - N and 57–161 mg/L TDS, respectively, which were well below the respective MCL and SMCL. The levelized cost of water treatment was in the range of ~$$2/m 3 - $$2.9/m 3 which aligns with typical residential water costs in California and in the study region, and monthly residential water costs (39 dollars-74 dollars/residential unit/month) were also within the range in California. The study showcased the DWTD approach as a viable and potentially scalable solution for upgrading impaired local potable water supply of communities lacking centralized water delivery infrastructure. However, streamlined permitting processes and standardized regulatory frameworks are critical to promoting wider adoption and maximizing the socio-economic benefits of the DWT approach. Moreover, DACs are likely to require government subsidies in order to cover the CapEx of DWTD systems in addition to upgrade of site infrastructure.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2015

Ro-vibrational averaging of the isotropic hyperfine coupling constant for the methyl radical

We present the first variational calculation of the isotropic hyperfine coupling constant of the carbon-13 atom in the CH{sub 3} radical for temperatures T = 0, 96, and 300 K. It is based on a newly calculated high level ab initio potential energy surface and hyperfine coupling constant surface of CH{sub 3} in the ground electronic state. The ro-vibrational energy levels, expectation values for the coupling constant, and its temperature dependence were calculated variationally by using the methods implemented in the computer program TROVE. Vibrational energies and vibrational and temperature effects for coupling constant are found to be in very good agreement with the available experimental data. We found, in agreement with previous studies, that the vibrational effects constitute about 44% of the constant’s equilibrium value, originating mainly from the large amplitude out-of-plane bending motion and that the temperature effects play a minor role.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2015

ON THE ASYMMETRY OF THE OH RO-VIBRATIONAL LINES IN HD 100546

We present multi-epoch high-spectral resolution observations with VLT/CRIRES of the OH doublet {sup 2}Π{sub 3/2} P4.5 (1+, 1–) (2.934 μm) toward the protoplanetary disk around HD 100546. The OH doublet is detected at all epochs and is spectrally resolved while nearby H{sub 2}O lines remain undetected. The OH line velocity profile is different in the three data sets: in the first epoch (2012 April, P.A. = 26°) the OH lines are symmetric and line broadening is consistent with the gas being in Keplerian rotation around the star. No OH emission is detected within a radius of 8-11 AU from the star: the line emitting region is similar in size and extent to that of the CO ro-vibrational lines. In the other two epochs (2013 March and 2014 April, P.A. = 90° and 10°, respectively) the OH lines appear asymmetric and fainter compared to 2012 April. We investigate the origin of these line asymmetries which were taken by previous authors as evidence for tidal interaction between a (unseen) massive planet and the disk. We show that the observed asymmetries can be fully explained by a misalignment of the slit of the order of 0.''04-0.''20 with respect to the stellar position. The disk is spatially resolved and the slit misalignment is likely caused by the extended dust emission which is brighter than the stellar photosphere at near-infrared wavelengths which is the wavelength used for the pointing. This can cause the photo-center of HD 100546 to be misaligned with the stellar position at near-infrared wavelengths.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2024

HERO WEC - Bills of Materials: WEC, RO System, and Submersible Pump

This submission includes detailed Bills of Materials for the NREL-designed and -built Hydraulic and Electric Reverse Osmosis Wave Energy Converter (HERO WEC), as well as the reverse osmosis assembly and submersible pump that are used in the HERO WEC. The WEC file is specific to the components and sub-components that are included on the in-water buoy portion of the WEC. The RO file is specific to the components and sub-components that are included on the reverse osmosis module that is used for both the hydraulic and electric configuration. The submersible pumps file is specific to the components and sub-components that are included on the submersible pump module that is used feed the reverse osmosis module when the HERO WEC is in the electric configuration. In addition to this submission, an additional submission available for the WEC model itself, including the power electronics enclosure, and reverse osmosis assembly that is needed to supply water in the electric submission. A link is provided below. More details on this project including data, CAD drawings, etc. can be found in the HERO-WEC main page link below. This data set has been developed by the National Renewable Energy Laboratory, operated by Alliance for Sustainable Energy, LLC, for the U.S. Department of Energy (DOE) under Contract No. DE-AC36-08GO28308. Funding provided U.S. Department of Energy Office of Energy Efficiency and Renewable Energy Water Power Technologies Office.

16 TIDAL AND WAVE POWER↗
DOE OSTI2016

( AKARI AKARI) near-infrared spectroscopy of the extended green object G318.05+0.09: detection of CO fundamental RO-vibrational emission

We present the results of near-infrared (2.5–5.4 μm) long-slit spectroscopy of the extended green object (EGO) G318.05+0.09 with AKARI. Two distinct sources are found in the slit. The brighter source has strong red continuum emission with H{sub 2}O ice, CO{sub 2} ice, and CO gas and ice absorption features at 3.0, 4.25 μm, 4.67 μm, respectively, while the other greenish object shows peculiar emission that has double peaks at around 4.5 and 4.7 μm. The former source is located close to the ultra compact H ii region IRAS 14498−5856 and is identified as an embedded massive young stellar object (YSO). The spectrum of the latter source can be interpreted by blueshifted (−3000 ∼ −6000 km s{sup −1}) optically thin emission of the fundamental ro-vibrational transitions (v=1--0) of CO molecules with temperatures of 12000–3700 K without noticeable H{sub 2} and H i emission. We discuss the nature of this source in terms of outflow associated with the young stellar object and supernova ejecta associated with a supernova remnant.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2016

A STUDY OF RO-VIBRATIONAL OH EMISSION FROM HERBIG Ae/Be STARS

We present a study of ro-vibrational OH and CO emission from 21 disks around Herbig Ae/Be stars. We find that the OH and CO luminosities are proportional over a wide range of stellar ultraviolet luminosities. The OH and CO line profiles are also similar, indicating that they arise from roughly the same radial region of the disk. The CO and OH emission are both correlated with the far-ultraviolet luminosity of the stars, while the polycyclic aromatic hydrocarbon (PAH) luminosity is correlated with the longer wavelength ultraviolet luminosity of the stars. Although disk flaring affects the PAH luminosity, it is not a factor in the luminosity of the OH and CO emission. These properties are consistent with models of UV-irradiated disk atmospheres. We also find that the transition disks in our sample, which have large optically thin inner regions, have lower OH and CO luminosities than non-transition disk sources with similar ultraviolet luminosities. This result, while tentative given the small sample size, is consistent with the interpretation that transition disks lack a gaseous disk close to the star.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2016

RO concentrated water treatment equipment for risk reduction of contaminated water stored in tank in Fukushima NPS - 16655

At the Fukushima Daiichi Nuclear Power Station (NPS) site, concentrated waste water was stored in tanks, awaiting treatment to remove radionuclides using various multi-nuclide removal systems. To accelerate the treatment for risk reductions of radiation dose and tank leakage, we constructed reverse-osmosis (RO) concentrated water treatment equipment. The equipment consists of filters and five adsorbent vessels containing Cs-Sr simultaneous adsorbents with the removal ability of Sr being 1/1000(max) to 1/100(min), and the overall treatment capacity of 500 to 900 m{sup 3}/day. We developed a simulation code to calculate the Sr concentration of outlet water for each vessel in order to evaluate the bed life of the media. The simulation code makes it possible to plan when to change media in the vessels during the equipment operation. The successful treatment of concentrated waste water was conducted using the equipment from January to May 2015. Total amount of water treated was 82,194 m{sup 3}. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2024

Machine learning models of intermittent operation of RO wellhead water treatment for salinity reduction and nitrate removal

Machine learning models were developed for intermittent multi-mode operation of a wellhead reverse osmosis water purification and desalination system to predict salt passage, nitrate passage, and permeate flux. The models, based on long short-term memory (LSTM) recurrent neural network (RNN) architecture, included an attention mechanism to increase model performance in proximity of the regulatory limit for nitrate. Training and testing of the models for the Startup, Production, Shutdown and Flushing operational modes were based on operational data (consisting of 22 process variables per data sample) acquired every 2–5 s over a six-month period. The significant sets of model input attributes for the different operational modes were assessed via Spearman ranking correlation, Self-Organizing Map (SOM) analysis and feed forward feature selection (FFFS). Although the variability of nitrate passage, salt passage and permeate flux was significant over the four operational modes, prediction performance for the three outcomes were with R2 and Average Absolute Relative Error (AARE) of 0.78–0.95 and 2.96–6.16 %, respectively. Model updates post membrane elements replacement demonstrated similar levels of prediction accuracy. The study results suggest that there is merit in exploring the utility of multi-mode models for sensor fault detection, data imputation, and for potential use in model-predictive control.

Intermittent RO operation↗
DOE OSTI2023

Plasma-parameter dependence of ro-vibrational temperatures for H 2 in LHD divertor

We analyzed a thousand visible spectra of Fulcher-α band measured for divertor plasmas in Large Helical Device. With a coronal model and Bayesian inference, the population distribution of hydrogen molecule in the electronic ground state was estimated. The non-thermal population distribution was recovered with a two-temperature model, which has two sets of rotational and vibrational temperatures, as well as their mixture coefficient. The lower rotational temperature significantly changes according to the plasma parameters. Its nearly linear dependence on the electron density was found, which is consistent with previous works. The lower vibrational temperature also shows a small density dependence, as reported by a previous work. On the other hand, the higher rotational and vibrational temperatures as well as the mixture coefficient only show slight changes over the broad range of plasma parameters. These population parameters show a significant correlation; with higher electron density, all the temperatures and the fraction of the higher-temperature component increase simultaneously. In conclusion, this suggests that the electron impact plays an important role to determine the population distribution.

42 ENGINEERING↗
DOE OSTI2025

Demonstrating the impact of ro-vibrationally excited H 2 on divertor detachment via population modelling

EDGE2D-EIRENE profiles characteristic for low recycling, high recycling and detached plasmas are postprocessed applying a vibrationally resolved collisional radiative (CR) model based on the Yacora solver to predict excited state densities and thus the molecular Lyman-, Werner- and Fulcher band emission intensities. These emission intensities are compared to predictions from the AMJUEL database standardly used in EIRENE. Lower Fulcher band and higher Lyman- and Werner band emission is predicted by the Yacora model in comparison to AMJUEL suggesting that inconsistent results from model based evaluation of measured spectra are expected depending on which model and molecular emission band is considered. The implications on detachment rate predictions are discussed.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2010

Ro-vibrational spectra of C 2 H 2 based on variational nuclear motion calculations

A published ab initio-based potential energy surface and newly constructed dipole moment surface of acetylene have been used to compute vibrational band intensities. The line intensity calculations employed the variational nuclear motion code WAVR4 for computation of wave functions and energy levels, and a newly developed code DIPOLE4 for computation of dipole transitions. Owing to the high computational cost of J>0 transitions using direct variational methods only J=0 and J=1 states and transitions have been computed variationally. The intensities of J>1 transitions were extrapolated from J=0 and J=1 using Honl-London coefficients. The resulting effective rotational constants B and transition intensities are compared with experimental data for the (3 nu(4)+nu(5)) combination band, the nu(3) and the nu(5) fundamental band. The prospects of using this procedure for extensive calculations of a hot line list, important for cool stars and extrasolar planets are discussed.

74 ATOMIC AND MOLECULAR PHYSICS↗
DOE OSTI2011

RO-VIBRATIONAL CO DETECTED IN THE {beta} PICTORIS CIRCUMSTELLAR DISK

We present high-resolution near-infrared spectra of {beta} Pictoris-a nearby young star with a debris disk. Fundamental low-J CO absorption lines are detected and strict upper limits are placed on the flux of v = 2-1 low-J CO emission lines. The limit on the UV fluorescent emission flux in the v = 2-1 lines is used to place a tight constraint on the inner extent of the CO gas. Assuming H I is the primary collision partner, the sub-thermal population of the low-J v = 0 rotational levels constrains the density of the gas in the disk to n{sub H} = (2.5{sup +7.1}{sub -1.2}) x 10{sup 5} cm{sup -3}. If the distribution of hydrogen follows that of the other metals in the disk, we find that the mass of the gas in the disk is 0.17{sup +0.47}{sub -0.08} M{sub +}. We compare this mass to the gas mass necessary to brake the metals in the disk through ion-neutral reactions.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2014

NEW ACCURATE MEASUREMENT OF {sup 36}ArH{sup +} AND {sup 38}ArH{sup +} RO-VIBRATIONAL TRANSITIONS BY HIGH RESOLUTION IR ABSORPTION SPECTROSCOPY

The protonated argon ion, {sup 36}ArH{sup +}, was recently identified in the Crab Nebula from Herschel spectra. Given the atmospheric opacity at the frequency of its J = 1-0 and J = 2-1 rotational transitions (617.5 and 1234.6 GHz, respectively), and the current lack of appropriate space observatories after the recent end of the Herschel mission, future studies on this molecule will rely on mid-infrared observations. We report on accurate wavenumber measurements of {sup 36}ArH{sup +} and {sup 38}ArH{sup +} rotation-vibration transitions in the v = 1-0 band in the range 4.1-3.7 μm (2450-2715 cm{sup –1}). The wavenumbers of the R(0) transitions of the v = 1-0 band are 2612.50135 ± 0.00033 and 2610.70177 ± 0.00042 cm{sup –1} (±3σ) for {sup 36}ArH{sup +} and {sup 38}ArH{sup +}, respectively. The calculated opacity for a gas thermalized at a temperature of 100 K and with a linewidth of 1 km s{sup –1} of the R(0) line is 1.6 × 10{sup –15} × N({sup 36}ArH{sup +}). For column densities of {sup 36}ArH{sup +} larger than 1 × 10{sup 13} cm{sup –2}, significant absorption by the R(0) line can be expected against bright mid-IR sources.

74 ATOMIC AND MOLECULAR PHYSICS↗