Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Fractionalization”

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 649 records · Page 36
All sourcesNASA NTRSDOE OSTI
DOE OSTI2021

Isotopic fractionation accompanying CO 2 hydroxylation and carbonate precipitation from high pH waters at The Cedars, California, USA

The Cedars ultramafic block hosts alkaline springs (pH > 11) in which calcium carbonate forms upon uptake of atmospheric CO 2 and at times via mixing with surface water. Here, these processes lead to distinct carbonate morphologies with “floes” forming at the atmosphere-water interface, “snow” of fine particles accumulating at the bottom of pools and terraced constructions of travertine. Floe material is mainly composed of aragonite needles despite CaCO 3 precipitation occurring in waters with low Mg/Ca (<0.01). Precipitation of aragonite is likely promoted by the high pH (11.5–12.0) of pool waters, in agreement with published experiments illustrating the effect of pH on calcium carbonate polymorph selection.

58 GEOSCIENCES↗
DOE OSTI2021

Phase 3 Multi-Center, Prospective, Randomized Trial Comparing Single-Dose 24 Gy Radiation Therapy to a 3-Fraction SBRT Regimen in the Treatment of Oligometastatic Cancer

This prospective phase 3 randomized trial was designed to test whether ultra high single-dose radiation therapy (24 Gy SDRT) improves local control of oligometastatic lesions compared to a standard hypofractionated stereotactic body radiation therapy regimen (3 × 9 Gy SBRT). The secondary endpoint was to assess the associated toxicity and the impact of ablation on clinical patterns of metastatic progression.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2021

Fractionated Radiation Severely Reduces the Number of CD8+ T Cells and Mature Antigen Presenting Cells Within Lung Tumors

The combination of standard-of-care radiation therapy (RT) with immunotherapy is moving to the mainstream of non-small cell lung cancer treatment. Multiple preclinical studies reported on the CD8{sup +} T cell stimulating properties of RT, resulting in abscopal therapeutic effects. A literature search demonstrates that most preclinical lung cancer studies applied subcutaneous lung tumor models. Hence, in-depth immunologic evaluation of clinically relevant RT in orthotopic lung cancer models is lacking.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2022

Gantry-Based 5-Fraction Elective Nodal Irradiation in Unfavorable-Risk Prostate Cancer: Outcomes From 2 Prospective Studies Comparing SABR Boost With MR Dose-Painted HDR Brachytherapy Boost

Guidelines from the American Society of Clinical Oncology and Cancer Care Ontario recommend brachytherapy boost for patients with intermediate-risk or high-risk prostate cancer. SABR is an emerging technique for prostate cancer, but its use in high-risk disease is limited. Efficacy, toxic effects, and quality of life (QoL) were compared in patients treated on 2 prospective protocols that used SABR boost or magnetic resonance–guided high-dose-rate brachytherapy (HDR-BT) boost with 6 to 18 months of androgen deprivation therapy (ADT).

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2022

Investigation of the fatigue crack behavior of 304 stainless steels using synchrotron X-ray tomography and diffraction: Influence of the martensite fraction and role of inclusions

Here, the effect of fatigue on the microstructure of four-point bend specimens of three variations of 304 stainless steels (Commercial 304, 304H, and 304 L) was investigated using synchrotron x-ray tomography and diffraction. X-ray tomography revealed the formation of the fatigue-induced microvoids and crack while the diffraction data was used to quantify the amount of deformation-induced martensite found after fatigue in all samples. Transmission electron microscopy evidenced the role of the precipitates/inclusions on the microvoid formation. It was found to depend on their chemical nature. The shape of the precipitates/inclusions was also found to have an effect on the microvoid shape.

304 stainless steel↗
DOE OSTI2025

Pressure-stable supported ionic liquid membranes using isoporous supports for evaluating pure- and mixed-gas light paraffin fractionation

Advances in horizontal drilling and hydraulic fracturing have spurred the growth of domestic U.S. energy production. Membranes, typically silicone rubbers, have found utility in shale gas treatment as fuel gas conditioning units to selectively remove C 2 + hydrocarbons at pressures up to 30 bar, producing clean CH 4 for gas engines. However, more selective materials could be beneficial for broader shale gas treatment applications, such as dew point control units. Supported ionic liquid membranes (SILMs) offer a potential opportunity for improving C 3 H 8 /CH 4 selectivity, but they lack pressure-stability. Here, we report C 3 H 8 /CH 4 selective and pressure-stable SILMs using isoporous supports. SILMs with supports that had minimal defects remained stable up to 15 bar of transmembrane pressure. This stability allowed for pure- and mixed-gas testing of the resulting membranes at elevated pressures. Furthermore, these tests revealed that low viscosity ILs (<100 cp) may display mixed-gas permeances and permselectivity nearly identical to pure-gas results. On the other hand, higher viscosity ILs may display increasing permeances and permselectivity with increasing C 3 H 8 fugacity, similar to rubbery polymers. Ultimately, the SILMs demonstrated relatively high pressure-stability due to the isoporous supports and competitive mixed-gas C 3 H 8 /CH 4 permselectivity compared to silicone rubber.

Rosenthal, Justin J. [University of Texas at Austi↗