Publications by authors named "J O Hammons"
One regime of experimental particle-laden flow study involves ejecta microjets-often defined as a stream of micrometer-scale particles generated through shock interaction with a non-uniform surface and generally travel above 1 km/s. In order to capture the change in characteristics as a function of propagation time, we apply a multi-frame x-ray radiography platform to observe and track the jet transport dynamics. A synchrotron x-ray source allows us to perform quantitative analyses and comparisons between the eight images captured by the imaging system.
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- Gas bubbles form during water electrolysis, where hydrogen and oxygen are generated, and they affect the electrode's performance by decreasing its active area.
- The study uses grazing incidence small-angle X-ray scattering (GISAXS) and optical microscopy to track how the size and coverage of nanobubbles evolve over time during the electrolysis process.
- It finds that as more charge is passed, the number of nanobubbles increases while their size decreases, and it suggests that reducing dissolved hydrogen could help minimize nanobubble coverage on the surface.
Article Synopsis
- Two-dimensional (2D) materials, especially peptoids, have gained attention for their diverse applications from chemical sensing to biomedicine due to their unique properties like high stability and self-repair.
- This study examined how different peptoid sequences affect their self-assembly into 2D crystalline sheets using techniques like Atomic Force Microscopy (AFM) and X-ray scattering.
- Results indicated that peptoids with specific structural characteristics influence their growth behavior on surfaces, revealing variations in assembly rates and stability based on sequence composition and hydrophobic interactions.
Background: Pancreatic ductal adenocarcinoma (PDAC) is an aggressive tumor. Prognosis is poor and survival is low in patients diagnosed with this disease, with a survival rate of ~12% at 5 years. Immunotherapy, including adoptive T cell transfer therapy, has not impacted the outcomes in patients with PDAC, due in part to the hostile tumor microenvironment (TME) which limits T cell trafficking and persistence.
View Article and Find Full Text PDFWe report a rhodium-catalyzed asymmetric addition of aryl and alkenyl boronic acids to quinoxalinium salts that generates dihydroquinoxalines with high enantioselectivity. Functionalization of the reaction products, dihydroquinoxaline, allows the preparation of tetrahydroquinoxalines with various substitution patterns.
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