The authors have devised an algorithm and made a program of 2-stage optimization of irradiation conditions. At the 1st stage geometric parameters of irradiation are selected (field sizes, their number, a tangential shift of the field axis) proceeding from the peculiarities of the position of tumors, vital organs and tissues in space in respect to a source for each irradiation direction. Dose optimization is done at the 2nd stage. Doses are calculated on the basis of empirical expressions for the distribution of a dose of single gamma- and inhibition radiation beams up to 42 MEV Tissue inhomogeneity and surface curvature are taken into consideration by means of corrections.
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Dalton Trans
January 2025
Department of Inorganic Chemistry, Shahid Beheshti University, 1983969411, Tehran, Iran.
In a systematic study, six pseudopolymorphic coordination polymers containing the ditopic 1,3-di(pyridin-4-yl)urea ligand (4bpu) constructed with d metal cations, possessing the formula {[M(4bpu)I]S} [(M = Zn, Cd and Hg), (S = MeOH or EtOH)], namely Zn-MeOH, Zn-EtOH, Cd-MeOH, Cd-EtOH, Hg- and Hg-EtOH were obtained. The title compounds were characterized by single-crystal X-ray diffraction analysis (SC-XRD), elemental analysis (CHN), FT-IR spectroscopy, thermogravimetric analysis (TGA), and powder X-ray diffraction (PXRD). The diffraction studies show that these compounds are isostructural 1D zig-zag chain coordination polymers which is also confirmed using XPac 2.
View Article and Find Full Text PDFFlow Turbul Combust
November 2024
Institut de Mécanique des Fluides de Toulouse, IMFT, CNRS, Université de Toulouse, Toulouse, France.
Improving mixing between two coaxial swirled jets is a subject of interest for the development of next generations of fuel injectors. This is particularly crucial for hydrogen injectors, where the separate introduction of fuel and oxidizer is preferred to mitigate the risk of flashback. Raman scattering is used to measure the mean compositions and to examine how mixing between fuel and air streams evolves along the axial direction in the near-field of the injector outlet.
View Article and Find Full Text PDFPeerJ
January 2025
Department of Magnetic Resonance Imaging, Hongqi Hospital, Mudanjiang Medical University, Mudanjiang, Heilongjiang, China.
Purpose: Few data are available on the causality of cerebral artery fenestration (CAF) triggering cerebral infarction (CI) and this study aims to identify representative morphological features that can indicate risks.
Methods: A cohort comprising 89 patients diagnosed with CAF were enrolled from a total of 9,986 cranial MR angiographies. These patients were categorized into Infarction Group ( = 55) and Control Group ( = 34) according to infarction events.
Phys Chem Chem Phys
January 2025
Department of Science Education, Graduate School of Humanities and Social Sciences, Hiroshima University, 1-1-1 Kagamiyama, Higashi-Hiroshima 739-8524, Japan.
The thermal dehydration of sodium carbonate monohydrate (SC-MH) exhibits kinetic characteristics that are typical of the thermal decomposition of solids with a reversible nature. One of the characteristics is the physico-geometrical constraints of the reaction due to the heterogeneous reaction feature. Another factor is the considerable impact of the atmospheric and self-generated water vapor on the kinetics.
View Article and Find Full Text PDFSci Rep
January 2025
College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing, 210098, China.
Internal instability of embankment soils under seepage can occur in two distinct ways: suffusion and suffosion. Suffusion involves the removal of fine particles from the matrix without causing significant disturbance to the soil skeleton, while suffosion is characterized by the movement of fine particles accompanied by skeleton collapse or deformation. In terms of dam safety, suffosion poses a greater threat than suffusion.
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