检索结果-南通市图书馆

Journal of Applied Mathematics and Physics 2020年第8期8卷 1535-1549页

作者： Matabara Dieng Babou Diop Malick Sow Youssou Gning Mamadi Biaye ababacar sadikhe ndao Ahmadou Wagué Department of Physics UFR-SATIC University Alioune Diop of Bambey Bambey Senegal Laboratoire Atomes-Lasers Department of Physics University Cheikh Anta Diop Dakar Senegal Department of Physics and Chemistry Faculty of Sciences and Technologies of Formation and Education University Cheikh Anta Diop Dakar Senegal

The doubly excited states of helium-like ions are investigated using a combination of the no-linear parameters of Hylleraas and the β-parameters of screening constant by unit nuclear charge. Calculations are performed for total energies of low-lying doubly excited states (N = 2 - 9) in He-like ions up to Z = 10. The results obtained from the novel method are in good agreement with the available theoretical calculations and experimental observations.

关键词： Electronic Correlations Variational Calculations Atoms And Ions Helium-Like Systems Singlet States Triplet States Matrix Elements Doubly-Excited States Autoionization

Utilizing Bayesian Modeling and MCMC for Accurate Characterization of Naturally Occurring Radionuclides Reference Background Levels in Mining Areas

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Nuclear Science and Technology 2024年第4期14卷 179-187页

作者： Djicknack Dione Papa Macoumba Faye Nogaye Ndiaye Moussa Hamady Sy Oumar Ndiaye Alassane Traoré ababacar sadikhe ndao Institute Technologies of Nuclear Applied Cheikh Anta Diop University of Dakar Dakar Senegal Department of Physics Faculty of Sciences and Techniques Cheikh Anta Diop University of Dakar Dakar Senegal

Statistical biases may be introduced by imprecisely quantifying background radiation reference levels. It is, therefore, imperative to devise a simple, adaptable approach for precisely describing the reference background levels of naturally occurring radionuclides (NOR) in mining sites. As a substitute statistical method, we suggest using Bayesian modeling in this work to examine the spatial distribution of NOR. For naturally occurring gamma-induced radionuclides like 232Th, 40K, and 238U, statistical parameters are inferred using the Markov Chain Monte Carlo (MCMC) method. After obtaining an accurate subsample using bootstrapping, we exclude any possible outliers that fall outside of the Highest Density Interval (HDI). We use MCMC to build a Bayesian model with the resampled data and make predictions about the posterior distribution of radionuclides produced by gamma irradiation. This method offers a strong and dependable way to describe NOR reference background values, which is important for managing and evaluating radiation risks in mining contexts.

关键词： Radionuclides Bayesian Modeling MCMC HDI 40K 232Th 238U

Multi-Elemental Analysis and 2D Image Mapping within Roots, Leaves and Seeds from O. glaberrima Rice Plants Using Micro-PIXE Technique

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Nuclear Science and Technology 2024年第2期14卷 97-106页

作者： Alassane Traore Anna Ndiaye Christopher Bongani Mtshali Manneh Baboucarr Jean Paul Latyr Faye Daouda Mbodj Kandiaba Traore Tapha Gueye ababacar sadikhe ndao Département de Physique Faculté des Sciences et Techniques Université Cheikh Anta Diop Dakar Senegal Département de Chimie Faculté des Sciences et Techniques Université Cheikh Anta Diop Dakar Senegal Tandetron Laboratory IBA Group iThemba LABS Cape Town South Africa Africa Rice Center St. Louis Senegal

Understanding metal accumulation at organ level in roots, leaves and seeds in O. glaberrima (OG) is crucial for improving physiological and metabolic aspects in growing Asian and African rice in salted areas. The micro-analytical imaging techniques are required to reveal its accumulation and distribution within plant tissues. PIXE studies have been performed to determine different elements in rice plants. The existing microbeam analytical technique at the iThemba LABS will be applied for the 2D image mapping of fresh rice tissues to perform a concentration of low atomic mass elements (such as Al, Si, P, S, Cl, Ca, Ti, Mn, Fe, Cu, Br, Zn and K) with detection limits of typically 1-10 μg/g. Comparison of the distribution of the elements between leaves, root and seed samples using uptake and distribution of elements in particular environmental conditions with potential amount of salt in water have been performed. We are also expecting to indicate metal exclusion as salt tolerance strategies from leaves, root, and seed compartments using matrix correlation between samples and between elements on rice species.

关键词： PIXE 2D Mapping Rice Concentration Elemental Analysis

Enhancing Precision in Radiotherapy Delivery: Validating Monte Carlo Simulation Models for 6 MV Elekta Synergy Agility LINAC Photon Beam Using Two Models of the GAMOS Code

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Nuclear Science and Technology 2024年第2期14卷 146-163页

作者： Nogaye Ndiaye Oumar Ndiaye Papa Macoumba Faye Kodjo Joël Fabrice N’Guessan Djicknack Dione Khady Sy Moussa Hamady Sy Jean Paul Latyr Faye Alassane Traoré ababacar sadikhe ndao Institute of Applied Nuclear Technology University Cheikh Anta Diop Dakar Senegal International Cancer Center of Dakar Dakar Senegal Department of Physics Faculty of Sciences and Technology University Cheikh Anta Diop Dakar Senegal

The most crucial requirement in radiation therapy treatment planning is a fast and accurate treatment planning system that minimizes damage to healthy tissues surrounding cancer cells. The use of Monte Carlo toolkits has become indispensable for research aimed at precisely determining the dose in radiotherapy. Among the numerous algorithms developed in recent years, the GAMOS code, which utilizes the Geant4 toolkit for Monte Carlo simula-tions, incorporates various electromagnetic physics models and multiple scattering models for simulating particle interactions with matter. This makes it a valuable tool for dose calculations in medical applications and throughout the patient’s volume. The aim of this present work aims to vali-date the GAMOS code for the simulation of a 6 MV photon-beam output from the Elekta Synergy Agility linear accelerator. The simulation involves mod-eling the major components of the accelerator head and the interactions of the radiation beam with a homogeneous water phantom and particle information was collected following the modeling of the phase space. This space was po-sitioned under the X and Y jaws, utilizing three electromagnetic physics mod-els of the GAMOS code: Standard, Penelope, and Low-Energy, along with three multiple scattering models: Goudsmit-Saunderson, Urban, and Wentzel-VI. The obtained phase space file was used as a particle source to simulate dose distributions (depth-dose and dose profile) for field sizes of 5 × 5 cm2 and 10 × 10 cm2 at depths of 10 cm and 20 cm in a water phantom, with a source-surface distance (SSD) of 90 cm from the target. We compared the three electromagnetic physics models and the three multiple scattering mod-els of the GAMOS code to experimental results. Validation of our results was performed using the gamma index, with an acceptability criterion of 3% for the dose difference (DD) and 3 mm for the distance-to-agreement (DTA). We achieved agreements of 94% and 96%, respective

关键词： GAMOS Monte Carlo LINAC Radiotherapy Dose Distribution Phase Space Gamma Index 6 MV Photon Beam

Multi-Elemental Analysis and 2D Image Mapping within Roots, Leaves and Seeds from O. glaberrima Rice Plants Using Micro-PIXE Technique

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Enhancing Precision in Radiotherapy Delivery: Validating Monte Carlo Simulation Models for 6 MV Elekta Synergy Agility LINAC Photon Beam Using Two Models of the GAMOS Code

World Journal of Nuclear Science and Technology（核科学与技术国际期刊） 2024年第2期 97页

作者： Alassane Traore Anna Ndiaye Christopher Bongani Mtshali Manneh Baboucarr Jean Paul Latyr Faye Daouda Mbodj Kandiaba Traore Tapha Gueye ababacar sadikhe ndao

来源：博看期刊评论

在线全文

博看期刊

学校读者我要写书评

暂无评论