Search results for "shielding"

Radiologische Veränderungen nach Implantation zweier unterschiedlicher zementfreier Hüftschaftsysteme

1997

PURPOSE: Of the study was to evaluate radiological alterations of the femoral bone after implantation of two different prostheses. METHODS: 81 patients with 87 hips underwent total hip arthroplasty by using the Zweymuller-stem fixating in the medullary canal, and 175 patients with 182 ABG-stems with a proximally fixating, anatomical design were followed up clinically and radiologically. RESULTS: Adaptive bone remodelling in Zweymuller-stems showed in some patients thickening of the cortex of the femur and proximal bone-stock loss; reactive lines were seen in the proximal areas surrounding the prosthesis. Radiographs of patients with ABG-stems showed these lines in the distal, smooth part of…

Broad beam transmission data for the shielding of brachytherapy facilities

2008

A Monte Carlo-aided design of a modular 241Am-Be neutron irradiator

2013

Monte Carlo studies aimed at designing a modular 241Am-Be neutron irradiator for testing neutron detectors and personal dosimeters and processing large volume samples are reported in this study. The evaluation of the shapes and thicknesses of the moderator and shielding materials was carried out by a MCNP5 Monte Carlo simulation code. The reliability of the simulation was experimentally verified by the activation of gold foils and TLD dosimeter measurements in an irradiation cell placed at the center of the test configuration.

Noble Gases as Magnetic Probes in Fullerene Chemistry

2016

Since the early 1990s of the previous century, the use of magnetic active noble gas atom to indirectly probe the size and symmetry of fullerene cage has been reviewed. Molecular modeling of nuclear shielding (and chemical shift) using gauge-including atomic orbital (GIAO) approach at several levels of theory, including Hartree–Fock (HF), density functional theory (DFT), and coupled cluster (CC), is discussed. The advantage of using GIAO calculation to predict and closely reproduce experimental 3He and 129Xe NMR spectra is shown.

Radiation protection of patients undergoing high-dose-rate brachytherapy: peripheral dose estimation, review of radiation risks and implant shielding…

2015

La braquiterapia (BT) es una modalidad de tratamiento de radioterapia en la que se coloca una fuente radiactiva encapsulada cerca, en contacto o en el interior del volumen a tratar. La desintegración de esta fuente produce la emisión de energía, lo que puede dar lugar a la muerte celular. Una dosis absorbida muy elevada (la dosis absorbida se define como la energía absorbida por unidad de masa) se deposita en un corto período de tiempo y en un pequeño número de fracciones. Para poder realizar un tratamiento de BT se requiere que el volumen de tratamiento sea accesible y bien delimitado en tamaño y forma. La BT se utiliza comúnmente como una modalidad de tratamiento eficaz para el cáncer de …

Compatibilization of Polylactide/Poly(ethylene 2,5-furanoate) (PLA/PEF) Blends for Sustainable and Bioderived Packaging.

2022

Despite the advantages of polylactide (PLA), its inadequate UV-shielding and gas-barrier properties undermine its wide application as a flexible packaging film for perishable items. These issues are addressed in this work by investigating the properties of melt-mixed, fully bioderived blends of polylactide (PLA) and poly(ethylene furanoate) (PEF), as a function of the PEF weight fraction (1–30 wt %) and the amount of the commercial compatibilizer/chain extender Joncryl ADR 4468 (J, 0.25–1 phr). J mitigates the immiscibility of the two polymer phases by decreasing and homogenizing the PEF domain size; for the blend containing 10 wt % of PEF, the PEF domain size drops from 0.67 &p…

Investigation of the Efficiency of Shielding Gamma and Electron Radiation Using Glasses Based on TeO2-WO3-Bi2O3-MoO3-SiO to Protect Electronic Circui…

2022

This research was funded by the Science Committee of the Ministry of Education and Science of the Republic of Kazakhstan (No. AP09058081). EP, EE, and AIP thank the Institute of Solid State Physics, University for their support. ISSP UL as the Center of Excellence is supported through the Framework Program for European universities Union Horizon 2020, H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under Grant Agreement No. 739508, CAMART2 project.

On the convergence of zero-point vibrational corrections to nuclear shieldings and shielding anisotropies towards the complete basis set limit in wat…

2016

The method and basis set dependence of zero-point vibrational corrections (ZPVCs) to nuclear magnetic resonance shielding constants and anisotropies has been investigated using water as a test system. A systematic comparison has been made using the Hartree–Fock, second-order Møller–Plesset perturbation theory (MP2), coupled cluster singles and doubles (CCSD), coupled cluster singles and doubles with perturbative triples corrections (CCSD(T)) and Kohn–Sham density functional theory with the B3LYP exchange-correlation functional methods in combination with the second-order vibrational perturbation theory (VPT2) approach for the vibrational corrections. As basis sets, the correlation consisten…