Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “SHIP”

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 433 records · Page 24
All sourcesNASA NTRSDOE OSTI
DOE OSTI2016

Shipping Grossly Dewatered resins in the RT-100 Type B Transportation Cask - 16068

Ion-exchange resins are used in the purification of coolant water in boiling water reactor nuclear power plants. The spent resins are a form of low-level or intermediate-level radioactive waste. These resins may have a relatively high specific activity level and are normally transported to a disposal facility within a secondary container placed in a Type B transportation cask. During transportation, hydrogen gas may build up in the cask due to radiolysis of the hydrogenous material in the contents. In the licensing process, a Type B cask is carefully analyzed to ensure that the maximum amount of hydrogen gas generated does not exceed 5%. The calculation to determine the mole fraction of hydrogen gas generated is a function of many variables, including the properties of the contents and the volume ratios of the contents. Because water generates hydrogen gas when it undergoes radiolysis, the amount of water present in the waste is normally limited. Typically, Type B transportation casks are allowed to carry dewatered resins, meaning less than 1% free-standing water by volume. To ensure compliance with this limitation, the dewatering process requires specialized equipment to pump the water from the secondary container. In an effort to enhance the usability of the RT-100 Type B transportation cask, Robatel Technologies re-analyzed the hydrogen gas generation calculation for contents including 'grossly dewatered' resins. Grossly dewatered resins are defined as resins containing less than 20% free-standing water by volume. This higher limit is made possible by a more thorough hydrogen gas generation calculation, which ensures that the flammability limit is not reached during shipment. In July 2015, The USNRC issued Revision 1 of the Certificate of Compliance for the Robatel Technologies RT-100 Type B transportation cask. This revision allows the cask to be used for grossly dewatered resins. With the revised Certificate of Compliance, the RT-100 is the first of its kind whose authorized contents include greater than 1% free liquids by volume. As a result of this change, the cask user can meet the 20% maximum free-standing water volume with a much simpler gravity-driven dewatering process. It is no longer necessary to have a complex dewatering system to ensure compliance with regulatory requirements. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2016

The Effectiveness of Gd Contents of Fuel Basket Wall in UNF Shipping and Storage Cask - 16598

A more effective basket structure, which employs the single wall basket structure and more effective neutron absorbing materials compared to the conventional 3 wall structure with boron neutron absorber, is under development. The criticality of the cask was evaluated as a function of the Gd and B contents in the plate and the Gd-containing SS plate thickness while maintaining the basic geometry the same as the reference cask which uses boron compound as neutron absorber. The KENO-VI code in SCALE with the data library ENDF/B-VII 238-group was used. In all the range of interest, the k{sub eff} values are below 0.4 which is much lower than licensing limit of 0.95. As Gd content increases, the k{sub eff} exponentially decreases. The Gd added SS shows higher performance than B added case in low atomic percent region. The B case curve showed less steep slope than the Gd case. The results of the wall thickness effect calculation indicated that the k{sub eff} decreases with thickness increase until ∼6 mm and it increases as thickness increases over ∼7 mm. (authors)

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2019

Influence of Cable Stiffness and Preload on Shipping Package Restraint Loads - 19381

Packages in transport are commonly secured using a combination of chock blocks and/or tensile tie-downs (chains, cables, straps). Analysis methods based on rigid body mechanics are commonly used to determine the load demands on the tie-downs. These methods require the system to be statically determinate. In order to be statically determinate, the restraints must meet specific stiffness criteria. This the selection of tie-downs and chocks should consider both the load rating and stiffness of the restraints. The criteria for restraint stiffness to meet rigid body mechanics is explained in this paper, along with the influence of cable angle and preload. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2026

Solar Heat for Industrial Processes: Integration with Chemical Reactors

The integration of solar thermal systems with chemical reactors has been proposed as part of a larger effort to develop and deploy solar heat for industrial processes (SHIP) technologies. A strong motivation for SHIP processes and technologies is the potential for high thermal efficiency coupled with low-cost thermal energy storage (TES) which can enable commercial deployment of such systems. While there are different ways to categorize SHIP technologies, one important such distinction is between directly irradiated systems and indirect off-sun process driven by a SHIP system. While directly irradiated systems can provide high thermal efficiencies and high fluxes, they usually require complex engineering solutions due to the need for redesigning the established processes and unit operations. In most cases, it is also more challenging to couple such a process to a TES system, losing some of the benefits of SHIP. On the other hand, using a SHIP system to drive an industrial process off-sun can allow better integration with existing process chains, easier TES capabilities, and potential for more applications fitting a specific SHIP technology. However, the integration of SHIP systems with the industrial processes is not fully explored in detail, especially in the case of high-temperature processes such as reforming, cracking, cement manufacturing, and iron/steelmaking. Many of these systems require heating fluxes of >50 kW/m^2, supplied via combustion of hydrocarbons in a fire box and benefitting from radiative heat transfer between the flue gases and the reaction zones. As such, using SHIP systems for such processes is more complex than providing the same thermal input in the form of a heat transfer medium (HTM) entering the reactor, kiln, or furnace. Moreover, in case convective heat transfer using SHIP is envisioned, for example using supercritical CO2 as the HTM from a particle receiver, the thermal integration might be more challenging than initially envisioned: lower heat transfer coefficients and limited approach temperature might require large flow rates, causing a mismatch between the process thermal requirements and the thermal capacity of the SHIP system. In addition, even if the heat exchange between SHIP and reactor is effective, there is still a cold leg HTM at the reaction temperature or slightly below it. Chemical plants usually include a set of heat exchangers, heat recovery steam generators, and even power generation units - in a tightly integrated design - to recover the flue gases which are eventually vented. With SHIP systems mostly operating on a closed HTM loop, bottoming the cold leg is crucial. In this talk, we will present different modeling results for a variety of syngas production reactions, using catalytic and chemical looping processes, and discuss some of the challenges and design considerations for off-sun chemical reactors using SHIP systems.

14 SOLAR ENERGY↗
DOE OSTI2024

Potential Availability of Alternative Fuel to Supply Maritime Activities in Pacific Northwest Ports

The international shipping sector represented 3% of global greenhouse gas emissions in 2023 (Office of Energy Efficiency & Renewable Energy 2024). International shipping has been classified as a difficult-to-decarbonize industry (IRENA 2024). In an effort to drive decarbonization, the U.S. Department of Energy has partnered with Mission Innovation to co-lead the Zero-Emission Shipping Mission, which launched in 2021(Office of Energy Efficiency & Renewable Energy 2021). In addition, the U.S. Department of State partnered with Norway to launch the Green Shipping Challenge in 2022 (Office of the Spokesperson 2022b). As part of the ZESM and Green Shipping Challenge, the United States is collaborating with the Republic of Korea (ROK) to develop a green shipping corridor (U.S. Mission Korea 2023). The United States and ROK have conducted a pre-feasibility study as the first step in developing a green shipping corridor between the countries. The ports included in the study are Seattle, Tacoma, and Everette in the U.S. Pacific Northwest (PNW) and Busan, Ulsan, and Masan in ROK. The National Renewable Energy Laboratory's role in the study was to analyze the availability and technical potential of alternative marine fuels in proximity to U.S. PNW ports. The findings show most of the existing alternative fuel capacity within the region is from renewable diesel, biodiesel, and sustainable aviation fuel facilities. The largest growth in fuel capacity in the region by 2030 is projected to be in renewable diesel and hydrogen. The overall technical readiness of non-drop-in alternative fuel production and conversion technologies is more developed than alternative-fueled ships and associated fueling infrastructure. However, much of the fuel capacity in the region is comprised of drop-in fuels, making it technically possible to use existing infrastructure for transporting and bunkering to the existing fleet. Data to inform regional alternative fuel quantity estimations were collected from an extensive review of databases, reports, announcements, and other publicly available resources. A maturity index and sector competition factor were applied to announced fuel projects to determine the quantity of alternative fuel available to the marine sector in the region by 2030. Demand data were collected from fuel bunkering logs covering the PNW seaports (State of Washington 2021). Both supply and demand data were converted to very-low sulfur fuel oil gallon equivalents (VLSFO-GE) for better comparison. Qualitative data were gathered through interviews with stakeholders, project developers, and industry experts. Total alternative fuel capacity available to the marine sector in the region is estimated to be 824 million VLSFO-GE per year by 2030. This is sufficient to cover the requirements of a green shipping corridor between the United States and ROK. The findings from this report are being used to inform detailed feasibility studies for several U.S. PNW -ROK green shipping corridors. Updates from the U.S. PNW - ROK feasibility studies will continue to be published on Mission Innovation's green corridor tracking website (Zero Emission Shipping Mission, n.d.). In addition, this report has helped to inform further work on shipping decarbonization in the U.S. PNW, including the Pacific Northwest to Alaska Green Corridor focused on cruise vessels.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
NASA NTRS2000

Advanced Shipboard Communications Demonstrations with ACTS

For ships at sea. satellites provide the only option for high data rate (HDR), long haul communications. Furthermore the demand for HDR satellite communications (SATCOM) for military and commercial ships. and other offshore platforms is increasing. Presently the bulk of this maritime HDR SATCOM connectivity is provided via C-band and X-band. However, the shipboard antenna sizes required to achieve a data rate of, say T 1 (1.544 Mbps) with present C-/X-band SATCOM systems range from seven to ten feet in diameter. This limits the classes of ships to which HDR services can be provided to those which are large enough to accommodate the massive antennas. With its high powered K/Ka-band spot beams, the National Aeronautics and Space Administration's (NASA) Advanced Communications Technology Satellite (ACTS) was able to provide T I and higher rate services to ships at sea using much smaller shipboard antennas. This paper discusses three shipboard HDR SATCOM demonstrations that were conducted with ACTS between 1996 and 1998. The first demonstration involved a 2 Mbps link provided to the seismic survey ship MN Geco Diamond equipped with a 16-inch wide, 4.5-inch tall, mechanically steered slotted waveguide array antenna developed by the Jet Propulsion Laboratory. In this February 1996 demonstration ACTS allowed supercomputers ashore to process Geco Diamond's voluminous oceanographic seismic data in near real time. This capability allowed the ship to adjust its search parameters on a daily basis based on feedback from the processed data, thereby greatly increasing survey efficiency. The second demonstration was conducted on the US Navy cruiser USS Princeton (CG 59) with the same antenna used on Geco Diamond. Princeton conducted a six-month (January-July 1997) Western Hemisphere solo deployment during which time T1 connectivity via ACTS provided the ship with a range of valuable tools for operational, administrative and quality-of-life tasks. In one instance, video teleconferencing (VTC) via ACTS allowed the ship to provide life-saving emergency medical aid, assisted by specialists ashore. to a fellow mariner - the Master of a Greek cargo ship. The third demonstration set what is believed to be the all-time SATCOM data rate record to a ship at sea, 45 Mbps in October 1998. This Lake Michigan (Chicago area) demonstration employed one of ACTS' fixed beams and involved the smallest of the three vessels, the 45-foot Bayliner M/V Entropy equipped with a modified commercial-off-the-shelf one-meter antenna. A variety of multi-media services were provided to Entropy through a stressing range of sea states. These three demonstrations provided a preview of the capabilities that could be provided to future mariners on a more routine basis when K/Ka-band SATCOM systems are widely deployed.

Axford, Roy A.↗
DOE OSTI2022

Hydrogen for Maritime Applications

The maritime industry is investigating a number of fuel options for reducing emissions, including liquefied natural gas (LNG), biofuels, and electrical drive systems powered by batteries and/or hydrogen-fueled fuel cells. Hydrogen-fueled ships offer the potential to significantly reduce, if not eliminate, regulated and unregulated pollutants in maritime applications. Argonne National Laboratory conducted preliminary comparisons of the total cost of ownership (TCO) of several classes of ships to determine how fuel cell technology compares to the current diesel technology, what advancements are needed for hydrogen fuel cell technology to be competitive in the future, and what applications may be appropriate for introducing fuel cells into the maritime industry. These studies included feeder container ships, harbor tugboats, river pushboats, and auto/passenger ferries. For this study, TCO was defined to include the cost of fuel, propulsion system, and fuel storage system, the levelized cost of propulsion/auxiliary engines, and the cost of annual maintenance and consumables. It did not include the cost of the vessel frame or other components, aside from the propulsion system, that the fuel cell and diesel ships have in common. A 10% internal rate of return (IRR) was applied to the initial capital investment and an installation cost factor of 20% was applied to the capital cost. The capital cost of each component (e.g., engine, fuel tank, motor, etc.) was amortized over a period of 20 years, except for the fuel cell system, which was amortized over 6 or 10 years depending on ship class. The initial comparisons for container ships indicate that fuel costs are by far the dominant contributor to the TCO. With the current low cost of low-sulfur marine gasoil (LSMGO) and relatively high cost of hydrogen, it is difficult for hydrogen to compete with LSMGO in container ship applications. The large energy demand for container ships also favors the use of the higher volumetric energy density LSMGO fuel, especially for longer voyages. The space required to store enough hydrogen for the same journey is larger than that needed to store diesel fuels and can reduce the available cargo carrying and revenue generating space available on the ship.

08 HYDROGEN↗
DOE OSTI2018

On the Use of Ocean Dynamic Temperature for Hurricane Intensity Forecasting

Sea surface temperature (SST) and the Tropical Cyclone Heat Potential (TCHP) are metrics used to incorporate the ocean's influence on hurricane intensification in the National Hurricane Center's Statistical Hurricane Intensity Prediction Scheme (SHIPS). While both SST and TCHP serve as useful measures of the upper-ocean heat content, they do not accurately represent ocean stratification effects. Here we show that replacing SST in the SHIPS framework with a dynamic temperature (Tdy), which accounts for the oceanic negative feedback to the hurricane's intensity arising from storm-induced vertical mixing and sea-surface cooling, improves the model performance. While the model with SST and TCHP explains nearly 41% of the variance in 36-hr intensity changes, replacing SST with Tdy increases the variance explained to nearly 44%. Our results suggest that representation of the oceanic feedback, even through relatively simple formulations such as Tdy, may improve the performance of statistical hurricane intensity prediction models such as SHIPS.

Balaguru, Karthik↗
DOE OSTI2019

Nuclear Data Sheets for A=266,270,274,278,282,286,290,294,298☆

Spectroscopic information such as production, identification, half-lives, decay modes and possible excited states for experimentally known nuclides of mass numbers 266, 270, 274, 278, 282, 286, 290, 294, and 298 are presented together with the recommended values, superseding information and data in the previous ENSDF and NDS evaluation by 2005Gu33. No nuclides have yet been identified for A=302. In the last 14 years, large amounts of new and definitive data on the superheavy nuclides (SHN) have become available, thus changing almost entirely the landscape of nuclear data in this mass region, as also indicated by a number of recent review articles: 2017Og01, 2016Ho09, 2016Ho06 (for fission barriers), 2015Og05, 2015Og07, 2015Mo25, 2015OgZX, 2013Th02, and 2011Og07. See 2016Ka49 for IUPAC technical discussions for the discovery of Z=117 (Ts), Z=115 (Mc), Z=113 (Nh), 2001Ka70 and 2003Ka71 for Z=110-112, 2011Ba54 for Z≥113, 2009Ba62 for Z=112, and 2016Ka50 for Z=118 (Og). A special issue of Nuclear Physics A444 (2015) is devoted to research on superheavy elements (SHE) with 27 articles. In particular, see article by 2015Ko20 on mass spectrometric searches for superheavy elements in terrestrial matter. See also Proceedings of Nobel Symposium NS160 ‘Chemistry and Physics of Heavy and Superheavy Elements’ published in Eur. Phys. Jour. Web of Conferences 131 (2016), in particular 2016UtZZ, 2016DmZZ and 2016HoZY. See also 2016DuZX for future prospects of discovery of elements beyond Z=118 A=266: {sup 266}Db, {sup 266}Sg, {sup 266}Bh, {sup 266}Hs and {sup 266}Mt are the experimentally identified nuclides with A=266. Identification of {sup 266}Lr from α decay of {sup 270}Db has been proposed by 2014Kh04 from experiments at GSI, but complete details and analyses of all the four decay chains reported in this experiment have not yet been published, and discussion in 2015Og05 review article considering their work from Dubna (2013Og04, 2011Og04) and from GSI (2014Kh04) still concluded that {sup 270}Db decayed dominantly by SF mode, in contrast with dominant α decay mode proposed by 2014Kh04. Experiments carried out at FLNR-JINR-Dubna in collaboration with LLNL and ORNL, GSI-SHIP facility, RIKEN, and LBNL facilities: {sup 266}Db from the α-decay of {sup 282}Nh in two correlated decay chains at Dubna; {sup 266}Sg as α-daughter of {sup 270}Hs in 12 correlated decay chains at Dubna and GSI; {sup 266}Bh in α decay of {sup 278}Nh in three correlated decay chains observed at RIKEN, and also directly with one event in {sup 249}Bk({sup 22}Ne,5n) at LBNL, and with four events in {sup 243}Am({sup 26}Mg,3n) at HIRFL-Lanzhou; {sup 266}Hs as α-daughter of {sup 270}Ds at GSI in two different experiments, six correlated decays in the first, and 25 decay chains in the second experiment, the analysis of which has not been fully reported as yet; and {sup 266}Mt directly in {sup 209}Bi({sup 58}Fe,n) reaction at GSI in two different experiments, observing three events in the first experiment and 12 events in the second, also produced in {sup 208}Pb({sup 59}Co,n) reaction at LBNL, observing five correlated decay chains. See also 2000Ho27 for discussion on {sup 266}Sg and {sup 266}Mt. A=270: {sup 270}Db, {sup 270}Bh, {sup 270}Hs, {sup 270}Mt and {sup 270}Ds are the experimentally identified nuclides with A=270 are presented. Experiments carried out at FLNR-JINR-Dubna in collaboration with LLNL and ORNL, GSI-SHIP facility, and RIKEN: {sup 270}Db from the decay of {sup 294}Ts in six correlated decay chains at Dubna and GSI; {sup 270}Bh as α great-granddaughter of {sup 282}Nh in two correlated decay chains observed at Dubna; {sup 270}Hs directly in {sup 248}Cm({sup 26}Mg,4n) reaction at GSI, and in {sup 226}Ra({sup 48}Ca,4n) reaction at Dubna; {sup 270}Mt as granddaughter of {sup 278}Ts in three correlated decay chains at RIKEN; and {sup 270}Ds directly in {sup 207}Pb({sup 64}Ni,n) at GSI in 33 correlated decay chains. A=274: {sup 274}Bh, {sup 274}Mt and {sup 274}Rg are the experimentally identified nuclides with A=274. Search for {sup 274}Ds in {sup 238}U({sup 40}Ar, 4n),E=5.7 MeV/nucleon reaction and subsequent α decays at GSI (1990Sc11) proved negative. Experiments carried out at FLNR-JINR-Dubna in collaboration with LLNL and ORNL, GSI-SHIP facility, and RIKEN: {sup 274}Bh from the decay of {sup 294}Ts in six correlated decay chains at Dubna and GSI, {sup 274}Mt produced as α daughter of {sup 282}Nh in two correlated decay chains observed at Dubna, and {sup 274}Rg as α daughter of {sup 278}Nh produced in three correlated decay chains at RIKEN. A=278: {sup 278}Mt, {sup 278}Rg and {sup 278}Nh are the experimentally identified nuclides with A=278. A very tentative evidence is provided for {sup 278}Bh and {sup 278}Hs from a chain originally observed and assigned to {sup 289}Fl by 1999Og10, but later reassigned by 2004Og10 to {sup 290}Fl, and further discussed in detail by 2016Ho09, where, based on systematics of α decays and SF half-lives, {sup 290}Fl is proposed to decay via ε mode to {sup 290}Nh, which then decays by an α chain, ending in {sup 278}Bh that decays by SF mode. Experiments carried out at FLNR-JINR-Dubna in collaboration with LLNL and ORNL labs in the USA, GSI-SHIP facility, and RIKEN: {sup 278}Mt from the decay of {sup 294}Ts in six correlated decay chains at Dubna and GSI, {sup 278}Rg produced as α daughter of {sup 282}Nh in two correlated decay chains observed at Dubna, and {sup 278}Nh produced directly in three correlated decay chains at RIKEN. A=282: {sup 282}Rg, {sup 282}Cn and {sup 282}Nh are the experimentally identified nuclides with A=282. A very tentative evidence is provided for {sup 282}Mt and {sup 282}Ds from a chain originally observed and assigned to {sup 289}Fl by 1999Og10, but later reassigned by 2004Og10 to {sup 290}Fl, and further discussed in detail by 2016Ho09, where, based on systematics of α decays and SF half-lives, {sup 290}Fl is proposed to decay via ε mode to {sup 290}Nh, which then decays by an α chain, ending in {sup 278}Bh that decays by SF mode. Experiments carried out at FLNR-Dubna, in collaboration with LLNL and ORNL labs in the USA, and at GSI-SHIP facility confirm the identification of these isotopes, {sup 282}Rg in α decay chain of {sup 294}Ts in six correlated decay chains at Dubna and GSI, {sup 282}Cn produced in four ways at Dubna: independently in one correlated decay chain, as α daughter of {sup 286}Lv in 11 correlated decay chains, as α grand-daughter of {sup 290}Lv in 12 correlated decay chains, as α great-grand daughter of {sup 294}Og in four correlated decay chains, and {sup 282}Nh produced at Dubna directly in two correlated decay chains. A=286: {sup 286}Nh and {sup 286}Fl are the only experimentally identified nuclides with A=286. A very tentative evidence is provided for {sup 286}Rg and {sup 286}Cn from a chain originally observed and assigned to {sup 289}Fl by 1999Og10, but later reassigned by 2004Og10 to {sup 290}Fl, and further discussed in detail by 2016Ho09, where, based on systematics of α decays and SF half-lives, {sup 290}Fl is proposed to decay via ε mode to {sup 290}Nh, which then decays by an α chain, ending in {sup 278}Bh that decays by SF mode. 2017Ka66 in experiments at RIKEN using GARIS separator interpret one correlated decay chain in three different ways, one involving possible production of {sup 294}Lv in {sup 248}Cm({sup 48}Ca,2n),E=261.6 MeV, and α decay to {sup 290}Fl which further decays to {sup 286}Cn. Experiments carried out at FLNR-Dubna, in collaboration with LLNL and ORNL labs in the USA, and at GSI-SHIP facility confirm the identification of these isotopes, {sup 286}Nh as α grand-daughter of {sup 294}Ts in six correlated decay chains, and {sup 286}Fl produced in three ways: independently in 11 correlated decay chains, as α daughter of {sup 290}Lv in 12 correlated decay chains, and as α grand-daughter of {sup 294}Og in four correlated decay chains. A=290: {sup 290}Mc and {sup 290}Lv are the only experimentally identified nuclides with A=290. A tentative evidence is provided for {sup 290}Nh and {sup 290}Fl from a chain originally observed and assigned to {sup 289}Fl by 1999Og10, but later reassigned by 2004Og10 to {sup 290}Fl, and further discussed in detail by 2016Ho09, where, based on systematics of α decays and SF half-lives, {sup 290}Fl is proposed to decay via ε mode to {sup 290}Nh, which then decays by an α chain, ending in {sup 278}Bh that decays by SF mode. 2017Ka66 in experiments at RIKEN using GARIS separator interpret one correlated decay chain in three different ways, one involving possible production of {sup 294}Lv in {sup 248}Cm({sup 48}Ca,2n),E=261.6 MeV, and α decay to {sup 290}Fl. Experiments carried out at FLNR-Dubna, in collaboration with LLNL and ORNL labs in the USA, and at GSI-SHIP facility confirm the identification of these isotopes, {sup 290}Mc as α daughter of {sup 294}Ts in six correlated decay chains, and {sup 290}Lv produced in two ways, independently in 14 correlated decay chains, and as α daughter of {sup 294}Og in four correlated decay chains. A=294: {sup 294}Ts and {sup 294}Og are the only experimentally identified nuclides with A=294. Experiments carried out at FLNR-Dubna, in collaboration with LLNL and ORNL labs in the USA, and at GSI-SHIP facility confirm the identification of these isotopes, with a total of six EVR-α-SF correlated decay chains observed for {sup 294}Ts and four for {sup 294}Og. Tentative identification of {sup 294}Lv is provided by 2017Ka66 from the observation one correlated event using GARIS-RIKEN facility, where this event is interpreted in three possible ways, two interpretations lead to production of {sup 293}Lv and successive odd-A nuclides of {sup 289}Fl, {sup 285}Cn and {sup 281}Ds, whereas the third prediction starts with the production of {sup 294}Lv and successive {sup 290}Fl and {sup 286}Cn nuclides. Search for {sup 294}Rg in natural gold materials (2011De03), and for {sup 294}Ds, {sup 294}Fl and {sup 294}Mc in natural Pt, Pb and Bi samples (2011De21) using accelerator mass spectroscopy (AMS) proved negative, with extremely low upper limits established. Also 1980St05 did not see any evidence for {sup 294}Ds in natural Pt sample using AMS. A=298: Search for {sup 298}120 through fusion-evaporation reaction at Dubna, and for {sup 298}Fl and {sup 298}Mc in natural Pt, Pb and Bi samples using accelerator mass spectroscopy (AMS) proved negative. Tentative assignment of three α-α-α decay chains by 2016Ho09 to {sup 299}120 in {sup 248}Cm({sup 54}Cr,3n){sup 299}120 at GSI was refuted by 2017He11, assigning these correlations to random events, instead. A=302: Fluorescent x rays from Z=120 element were observed by 2012Fr03 from compound nucleus {sup 302}120 produced in {sup 238}U({sup 64}Ni,X),E=6.6 MeV/nucleon at GANIL, and x-ray yields were measured, together with minimum average time deduced from x-ray multiplicity. The compound nucleus could decay by 3n- or 4n-channels to produce {sup 299}120 or {sup 298}120. 2012He05 and 2016Ho09 also produced {sup 302}120 compound nucleus in {sup 248}Cm({sup 54}Cr, xn){sup 302}120{sup *},E=6.035 MeV/nucleon; and {sup 238}U({sup 64}Ni,xn){sup 302}120{sup *},E=5.53 MeV/nucleon reactions using UNILAC at GSI. Three α-α-α correlated decays from {sup 248}Cm({sup 54}Cr,xn){sup 302}120{sup *} reaction were tentatively assigned by 2016Ho09 to {sup 299}120 decay, however, a detailed analysis by 2017He11 refuted this claim, ascribing these events to random sequences. There are no data tables for A=302.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2021

Large Vessel Activity and Low-Frequency Underwater Sound Benchmarks in United States Waters

Chronic low-frequency noise from commercial shipping is a worldwide threat to marine animals that rely on sound for essential life functions. Although the U.S. National Oceanic and Atmospheric Administration recognizes the potential negative impacts of shipping noise in marine environments, there are currently no standard metrics to monitor and quantify shipping noise in U.S. marine waters. However, one-third octave band acoustic measurements centered at 63 and 125 Hz are used as international (European Union Marine Strategy Framework Directive) indicators for underwater ambient noise levels driven by shipping activity. We apply these metrics to passive acoustic monitoring data collected over 20 months in 2016–2017 at five dispersed sites throughout the U.S. Exclusive Economic Zone: Alaskan Arctic, Hawaii, Gulf of Mexico, Northeast Canyons and Seamounts Marine National Monument (Northwest Atlantic), and Cordell Bank National Marine Sanctuary (Northeast Pacific). To verify the relationship between shipping activity and underwater sound levels, vessel movement data from the Automatic Identification System (AIS) were paired to each passive acoustic monitoring site. Daily average sound levels were consistently near to or higher than 100 dB re 1 μPa in both the 63 and 125 Hz one-third octave bands at sites with high levels of shipping traffic (Gulf of Mexico, Northeast Canyons and Seamounts, and Cordell Bank). Where cargo vessels were less common (the Arctic and Hawaii), daily average sound levels were comparatively lower. Specifically, sound levels were ~20 dB lower year-round in Hawaii and ~10-20 dB lower in the Alaskan Arctic, depending on the season. Although these band-level measurements can only generally facilitate differentiation of sound sources, these results demonstrate that international acoustic indicators of commercial shipping can be applied to data collected in U.S. waters as a unified metric to approximate the influence of shipping as a driver of ambient noise levels, provide critical information to managers and policy makers about the status of marine environments, and to identify places and times for more detailed investigation regarding environmental impacts.

54 ENVIRONMENTAL SCIENCES↗