A proton beam is extracted from the 200-MeV linear accelerator at the Fermi National Accelerator Laboratory to investigate the efficacy of proton radiography in medical diagnosis. Fluence rates from 2 X 10(3) to 2 X 10(5) protons/cm2s over a 28-cm diameter field are obtained with a full width at half-maximum beam-energy spread of less than 3.61 MeV. The system is designed to radiography most parts of the human body, including the head, with high-speed screen-film as the imaging medium. Beam extraction and test results along with the medical implications of the beam quality are reported.
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http://dx.doi.org/10.1118/1.594426 | DOI Listing |
Nanomaterials (Basel)
December 2024
Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), Portici Research Centre, P.le E. Fermi 1, Portici, 80055 Naples, Italy.
In recent years, the morphology control of semiconductor nanomaterials has been attracting increasing attention toward maximizing their functional properties and reaching their end use in real-world devices. However, the development of easy and cost-effective methods for preparing large-scale patterned semiconductor structures on flexible temperature-sensitive substrates remains ever in demand. In this study, vapor post-treatment (VPT) is investigated as a potential, simple and low-cost post-preparative method to morphologically modify gravure-printed zinc oxide (ZnO) nanoparticulate thin films at low temperatures.
View Article and Find Full Text PDFAdv Sci (Weinh)
December 2024
Shenzhen Key Laboratory of Advanced Thin Films and Applications, College of Physics and optoelectronic engineering, Shenzhen University, Shenzhen, 518060, P. R. China.
Crystalline thermoelectric materials, especially SnSe crystals, have emerged as promising candidates for power generation and electronic cooling. In this study, significant enhancement in ZT is achieved through the combined effects of lattice distortions and band convergence in multiple electronic valence bands. Density functional theory (DFT) calculations demonstrate that cation vacancies together with Pb substitutional doping promote the band convergence and increase the density of states (DOS) near the Fermi surface of SnSe, leading to a notable increase in the Seebeck coefficient (S).
View Article and Find Full Text PDFAdv Sci (Weinh)
December 2024
Department of Physics, University of Basel, Klingelbergstrasse 82, Basel, 4056, Switzerland.
Many-body interactions in metal-organic frameworks (MOFs) are fundamental for emergent quantum physics. Unlike their solution counterpart, magnetization at surfaces in low-dimensional analogues is strongly influenced by magnetic anisotropy (MA) induced by the substrate and still not well understood. Here, on-surface coordination chemistry is used to synthesize on Ag(111) and superconducting Pb(111) an iron-based spin chain by using pyrene-4,5,9,10-tetraone (PTO) precursors as ligands.
View Article and Find Full Text PDFJ Phys Chem Lett
December 2024
Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Joint International Research Laboratory of Carbon-Based Functional Materials and Devices, Soochow University, Suzhou 215123, P. R. China.
Alkali element doping has significant physical implications for two-dimensional materials, primarily by tuning the electronic structure and carrier concentration. It can enhance interface electronic interactions, providing opportunities for effective charge transfer at metal-organic interfaces. In this work, we investigated the effects of gradually increasing the level of K doping on the lattice structure and electronic properties of an organometallic coordinated Kagome lattice on a Ag(111) surface.
View Article and Find Full Text PDFNano Lett
December 2024
SKKU Advanced Institute of Nano Technology and Department of Nano Science and Technology, Sungkyunkwan University, Suwon 16419, Republic of Korea.
In two-dimensional (2D) nanomaterial electronics, vertical field-effect transistors (VFETs), where charges flow perpendicular to the channel materials, hold promise due to the ease of forming ultrashort channel lengths by utilizing the thinness of 2D materials. However, the poor performance of p-type VFET arises from the lack of a gate-field-penetrating electrode with suitable work functions, which is essential for VFET operation. This motivated us to replace graphene (work function of ∼4.
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