Long time ion irradiation of surfaces under tilted incidence causes formation of regular nanostructures known as surface ripples. The nature of mechanisms leading to ripples is still not clear, this is why computational methods can shed the light on such a complex phenomenon and help to understand which surface processes are mainly responsible for it. In this work, we analyse the surface response of two materials, a semiconductor (silicon) and a metal (aluminium) under irradiation with the 250 eV and 1000 eV Ar ions focused at 70° from the normal to the surface. We simulate consecutive ion impacts by the means of molecular dynamics to investigate the effect on ripple formation. We find that the redistribution mechanism seems to be the main creator of ripples in amorphous materials, while the erosion mechanism is the leading origin for the pattern formation in crystalline metals.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1088/1361-648X/aaf59f | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
In vivo, online label-free monitoring of heterogenous oxygen utilization during phototherapy with real-time ultrasound-guided photoacoustic imaging.
bioRxiv
December 2024
Department of Biomedical Engineering, Tufts University, MA, USA.
Understanding the tumor microenvironment, particularly the vascular density and the availability of oxygen, is key in individualizing treatment approaches and determining their efficacy. While there are many therapies including radiotherapy that are ineffective in hypoxic tumor microenvironments, here we demonstrate the heterogeneous oxygen consumption during photodynamic therapy (PDT), a non-invasive treatment method using localized light to activate a photosensitive drug in the presence of oxygen that has shown high effectiveness in the treatment of various types of tumors, including those presented in head and neck cancer (HNC) patients. While our previous work has demonstrated that blood oxygen saturation (StO) mapped before and after treatment with ultrasound-guided photoacoustic imaging (US-PAI) can be used as a surrogate marker for the regionalized long-term efficacy of PDT, real-time monitoring of StO during PDT could provide additional insights on oxygen consumption and inform dose design for "on the spot" treatment decisions.
View Article and Find Full Text PDFThe photosensitive endoplasmic reticulum-chloroplast contact site.
J Microsc
December 2024
Biology Department and the Molecular and Environmental Plant Sciences Program, Texas A&M University, College Station, Texas, USA.
The endoplasmic reticulum (ER) forms contact sites with the chloroplast. Exposing contact sites that contain both the chloroplast and the ER to localised high-fluence, wavelength specific, 405 nm violet light, hereinafter referred to as photostimulation, induces multiple, potentially interacting intra- and intercellular responses. The responses vary depending on the tissue type of the cell and the chloroplast.
View Article and Find Full Text PDFUV-induced reactive oxygen species and transcriptional control of 3-deoxyanthocyanidin biosynthesis in black sorghum pericarp.
Front Plant Sci
October 2024
Department of Horticultural Sciences, Texas A&M University, College Station, TX, United States.
Black pericarp sorghum has notable value due to the biosynthesis of 3-deoxyanthocyanidins (3-DOAs), a rare class of bioactive polyphenols valued as antioxidant food additives and as bioactive compounds with cytotoxicity to human cancer cells. A metabolic and transcriptomic study was conducted to ascertain the cellular events leading to the activation of 3-DOA biosynthesis in black sorghum pericarp. Prolonged exposure of pericarp during grain maturation to high-fluence ultraviolet (UV) light resulted in elevated levels of reactive oxygen species (ROS) and the activation of 3-DOA biosynthesis in pericarp tissues.
View Article and Find Full Text PDFDeveloping power plant materials using the life cycle lens.
Philos Trans A Math Phys Eng Sci
October 2024
Materials Division, UK Atomic Energy Authority, Culham Science Centre, Abingdon, Oxfordshire OX14 3DB, UK.
The Spherical Tokamak for Energy Production (STEP) environment will include magnetic, thermal, mechanical and environmental loads far greater than those seen in the Joint European Torus campaigns of the past decade or currently contemplated for ITER. Greater still are the neutron peak dose rates of 10 displacements per atom, per second, which in-vessel materials in STEP are anticipated to be exposed to. Reduced activation and high-fluence resilience therefore dominate the materials strategy to support the STEP Programme.
View Article and Find Full Text PDFMicrochanneling and ultrasonic delivery of gold and platinum nanoparticles for selective photothermolysis of sebaceous follicles in the treatment of acne: a pilot study using porcine skin.
Lasers Med Sci
July 2024
Department of Dermatology, Kyung Hee University College of Medicine, Kyung Hee University Hospital, #23, Kyung Hee Dae-ro, Dongdaemun-gu, Seoul, 02447, Korea.
Purpose: Several treatment options for acne vulgaris are limited by their associated adverse effects. An innovative approach involves introducing light-absorbing nanoparticles into sebaceous follicles before destroying the follicles using selective photothermolysis. We aimed to investigate efficient methods for introducing gold and platinum nanoparticles into sebaceous follicles and to identify suitable laser equipment and parameters for the effective destruction of these follicles.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!