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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 469 records · Page 26
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Beam test performance studies of CMS Phase-2 Outer Tracker module prototypes

A new tracking detector will be installed as part of thePhase-2 upgrade of the CMS detector for the high-luminosity LHC era.This tracking detector includes the Inner Tracker, equipped withsilicon pixel sensor modules, and the Outer Tracker, consisting ofmodules with two parallel stacked silicon sensors. The Outer Trackerfront-end ASICs will be able to correlate hits from chargedparticles in these two sensors to perform on-module discriminationof transverse momenta (p$_{T}$). The p$_{T}$information is generated at a frequency of 40 MHz and will be usedin the Level-1 trigger decision of CMS. Prototypes of theso-called 2S modules were tested at the Test Beam Facility at DESYHamburg between 2019 and 2020. These modules use the finalfront-end ASIC, the CMS Binary Chip (CBC), and for the firsttime the Concentrator Integrated Circuit (CIC), optical readoutand on-module power conversion. In total, seven modules were tested,one of which was assembled with sensors irradiated with protons. Animportant aspect was to show that it is possible to read out modulessynchronously. A cluster hit efficiency of about 99.75 % wasachieved for all modules. The CBC p$_{T}$ discriminationmechanism has been verified to work together with the CIC andoptical readout. The measured module performance meets therequirements for operation in the upgraded CMS tracking detector.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2017

Ultrafast X-Ray Diffraction Studies of the Phase Transitions and Equation of State of Scandium Shock Compressed to 82 GPa

Using x-ray diffraction at the Linac Coherent Light Source x-ray free-electron laser, we have determined simultaneously and self-consistently the phase transitions and equation of state (EOS) of the lightest transition metal, scandium, under shock compression. On compression scandium undergoes a structural phase transition between 32 and 35 GPa to the same bcc structure seen at high temperatures at ambient pressures, and then a further transition at 46 GPa to the incommensurate host-guest polymorph found above 21 GPa in static compression at room temperature. Furthermore, shock melting of the host-guest phase is observed between 53 and 72 GPa with the disappearance of Bragg scattering and the growth of a broad asymmetric diffraction peak from the high-density liquid.

36 MATERIALS SCIENCE↗
DOE OSTI2015

Ultra-small-angle X-ray scattering study of second- phase particles in heat-treated Zircaloy-4

The ultra-small-angle X-ray scattering (USAXS) technique has been used to investigate and to quantify the morphology and size distribution of secondphase particles in Zircaloy-4 under various heat-treatment conditions. The alloy samples were solutionized in the phase field at 1293 K for 15 min and then cooled at different rates, including water quenching, air cooling and furnace cooling. The water-quenched samples were subsequently subjected to a thermal aging treatment at 873 K for different aging times (30, 60, 120 and 300 min). The USAXS results show that water quenching and air cooling from the phase field produces a narrow size distribution of fine-size precipitates with an average diameter of 300–800 A ° , while furnace cooling resulted in coarsening of the particles, with a broad size distribution having an average precipitate size of 600–1200 A ° . Further, the furnace-cooled sample shows a higher volume fraction of particles than the water-quenched or air-cooled sample. The USAXS results on the quenched then aged samples show that aging at 873 K for 10 min resulted in very fine size precipitates with an average diameter of 200–350 A ° . A rapid precipitation with the highest number density of second-phase particles amongst all the heat-treated samples (4.3 1020 m3) was observed in the sample aged for 10 min at 873 K. Particles of larger size and with a broad size distribution were observed in the sample aged at 873 K for 300 min. A bimodal type of particle size distribution was observed in all the heat-treated samples. Important parameters in the characterization of second-phase particles, such as the average size, size distribution, volume fraction and number density, were evaluated and quantified. These parameters are discussed for both heat-treated and aged specimens. Transmission and scanning transmission electron microscopy characterization were carried out on all heat-treated samples, to assist in interpretation and to substantiate the results from the USAXS measurements.

Srirangam, Prakash↗
DOE OSTI2015

Distribution of elastic strains appearing in gallium arsenide as a result of doping with isovalent impurities of phosphorus and indium

The distribution of elastic strains in a system consisting of a quantum-dot layer and a buried GaAs{sub x}P{sub 1−x} layer is studied using geometric phase analysis. A hypothesis is offered concerning the possibility of controlling the process of the formation of InAs quantum dots in a GaAs matrix using a local isovalent phosphorus impurity.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Adjuvant Hepatic Arterial Infusion Pump Chemotherapy After Resection of Colorectal Liver Metastases: Results of a Safety and Feasibility Study in The Netherlands

Background: The 10-year overall survival with adjuvant hepatic arterial infusion pump (HAIP) chemotherapy after resection of colorectal liver metastases (CRLMs) was 61% in clinical trials from Memorial Sloan Kettering Cancer Center. A pilot study was performed to evaluate the safety and feasibility of adjuvant HAIP chemotherapy in patients with resectable CRLMs. Study Design: A phase II study was performed in two centers in The Netherlands. Patients with resectable CRLM without extrahepatic disease were eligible. All patients underwent complete resection and/or ablation of CRLMs and pump implantation. Safety was determined by the 90-day HAIP-related postoperative complications from the day of pump placement (Clavien–Dindo classification, grade III or higher) and feasibility by the successful administration of the first cycle of HAIP chemotherapy. Results: A total of 20 patients, with a median age of 57 years (interquartile range [IQR] 51–64) were included. Grade III or higher HAIP-related postoperative complications were found in two patients (10%), both of whom had a reoperation (without laparotomy) to replace a pump with a slow flow rate or to reposition a flipped pump. No arterial bleeding, arterial dissection, arterial thrombosis, extrahepatic perfusion, pump pocket hematoma, or pump pocket infections were found within 90 days after surgery. After a median of 43 days (IQR 29–52) following surgery, all patients received the first dose of HAIP chemotherapy, which was completed uneventfully in all patients. Conclusion: Pump implantation is safe, and administration of HAIP chemotherapy is feasible, in patients with resectable CRLMs, after training of a dedicated multidisciplinary team.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2016

In-situ crystal structure determination of seifertite SiO 2 at 129 GPa: Studying a minor phase near Earth’s core–mantle boundary

Seifertite SiO₂ likely exists as a minor phase near the core–mantle boundary. By simulating the pressure and temperature conditions near the core–mantle boundary, seifertite was synthesized as a minor phase in a coarse-grained, polycrystalline sample coexisting with the (Mg,Fe)SiO₃ post-perovskite (pPv) phase at 129 GPa and 2500 K. Here we report the first in situ single-crystal structure determination and refinement of seifertite at high pressure and after a temperature quench from laser heating. We improved the data coverage of a minor phase from a diamond-anvil cell (DAC) by merging single-crystal data of seifertite from six selected grains that had different orientations. Observed systematic absences of reflections from the six individual grains allowed only one space group: Pbcn . The refined results of seifertite are in good agreement with the predictions from previous first-principles calculations at high pressure. This approach provides a method for structure determination of a minor phase in a mineral assemblage synthesized under P-T conditions representative of the deep Earth.

58 GEOSCIENCES↗
DOE OSTI2013

Phase 1 Feasibility Study, Canby Cascaded Geothermal Project, April 2, 2013

A small community in Northern California is attempting to use a local geothermal resource to generate electrical power and cascade residual energy to an existing geothermal district heating system, greenhouse, and future fish farm and subsequent reinjection into the geothermal aquifer, creating a net-zero energy community, not including transportation.

15 GEOTHERMAL ENERGY↗
DOE OSTI2018

Chemical Composition Analysis and Product Consistency Tests of the ORP Phase 5 Nepheline Study Glasses

In this report, the Savannah River National Laboratory (SRNL) provides chemical analyses and Product Consistency Test (PCT) results for a series of simulated high-level waste glass compositions fabricated by the Pacific Northwest National Laboratory (PNNL). These data will be used in the development of improved models for the prediction of nepheline crystallization in support of the Hanford Tank Waste Treatment and Immobilization Plant (WTP).

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2018

The experimental study of the phase structure of strongly interacting matter

Over the duration of the project period, our research has been focused on the beam energy scan data conducted at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory in order to search for the location of the Critical End Point (CEP) temperature or cross-over in the nuclear phase diagram using the STAR detector at RHIC and to determine the Equation of State (EOS) and the QGP transport coefficients. Working at the RHIC early on, we discovered the Long Range forward-backward multiplicity Correlations (LRC) which quantitatively confirmed the predictions of saturation models, in particular, the Color Glass Condensate (CGC) and the Color String Percolation Model (CSPM). We have used the CSPM to extract the initial temperature from the data. The clustering of color sources may be the way to achieve thermalization in A-A and N-N collisions. Recently we also used CSPM to measure the shear viscosity to entropy ratio at RHIC and LHC temperatures. The ratios are in agreement with values expected for a strongly interacting QGP. The thermodynamic quantities,temperature and the equation of state are in agreement with lattice QCD.

42 ENGINEERING↗
DOE OSTI2019

Chemical Composition Analysis and Product Consistency Tests of the ORP Phase 6 Nepheline Study Glasses

In this report, Savannah River National Laboratory (SRNL) provides chemical analyses and Product Consistency Test (PCT) results for a series of simulated high-level waste (HLW) glass compositions fabricated at Pacific Northwest National Laboratory (PNNL). The results of this effort will improve the ability to predict the impacts of glass composition and nepheline crystallization on the durability of HLW glasses. Chemical analyses were performed on a representative sample of each of the quenched glasses to allow for comparisons with the targeted compositions. A review of the individual glass composition measurements identified no analytical issues of concern. Minor differences between the targeted and measured concentrations of some of the baseline glass components were noted, including some high values for Fe 2 O 3 , and some low values for Al 2 O 3 , Li 2 O, Na 2 O and P 2 O 5 . The PCT Method-A was performed in triplicate on each of the quenched and canister centerline cooled (CCC) versions of the glasses to assess chemical durability. A review of the leachate analyses and standard solution data identified no issues with the analytical methods. Some of the CCC versions of the study glasses have normalized concentration for boron (NC B ) values that are higher than the Environmental Assessment glass benchmark NC B value of 16.695 g/L. For some of the study glasses, the NC B values were higher after the CCC heat treatment. The normalized concentrations for lithium and sodium (NC Li and NC Na ) followed this same trend. For many of these glasses, the changes in the normalized concentration for silicon (NC Si ) values were not congruent with the changes in NC B , NC Li , and NC Na values. It may be valuable for PNNL to perform a more complete review of the influence of composition and heat treatment on the PCT responses of the glasses described in this report to draw further conclusions, including any potential correlations with the methods used in selecting these glass compositions for study.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Hydrogen Based Energy Storage System for Integration with Dispatchable Power Generator (Phase I Feasibility Study)

This project examined the feasibility of integrating hydrogen generation, storage, and use as a means to decarbonize campus activities while retaining the ability to utilize the existing natural gas fired combined heat and power system installed at the campus of the University of California @ Irvine. Analysis of specific potential sites for the integrated system identified a location adjacent to the existing central plant which resulted in minimization of interconnections. A strategy based on use of commercial electrolyzers and gas storage was identified. Primary technology advancements are required for the gas turbine to accommodate higher levels of hydrogen and the integrated controls. The project indicated challenges for adopting the proposed strategy with the present rates and constraints. The availability of a relatively low-cost biogas resource by the campus already decarbonizes the gas turbine to some extent. In the absence of this resource, procurement of electricity directly from large scale renewable operations could facilitate lower electricity costs. Additional solar resources on campus could also help in this regard. The gas turbine cannot be operated below 50% capacity due to air permit constraints. Using the otherwise curtailed gas turbine operation to generate hydrogen via electrolysis by consuming natural gas is not highly efficient and therefore leads to relatively high costs of electricity returned. Several scenarios demonstrate potential for effective decarbonization, yet most involve lower and lower capacity factor for the legacy gas turbine which is not a good use of the asset. A small gas turbine output with higher efficiency operation would help. As would ability to export electricity to the grid. Certainly current rate structures and operational scenarios are less attractive than other possible future structures which should be pushed for in the future.

03 NATURAL GAS↗