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Evaluation of natural radionuclide content in Nile river sediments and excess lifetime cancer risk associated with gamma radiation

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Iranian Journal of Medical physics 2019年第1期16卷 27-33页

作者： El-Taher, Atef Najam, Laith Ahmed Hussian, Imad Omer, Mohammed Ahmed Ali Department of Physics Faculty of Science Al-Azhar University Cairo Egypt Department of Physics Faculty of Science University of Mosul Mosul Iraq Department of Radiologic Technology Faculty of Applied Medical Sciences Qassim University Buraydah Saudi Arabia Faculty of Medical Radiology Sudan University of Science and Technology Khartoum Sudan

Introduction: This Study has was carried out to measure and detect the natural occurred radionuclide content including 226Ra, 232Th and 40K in the Nile River sediments at various locations in Upper Egypt, from Aswan to El-Minya. Additionally, we determine the absorbed dose rate, the annual effective dose equivalent, and excess lifetime cancer risk also has been calculated. Material and Methods: The gamma ray measurements were performed with a high resolution High-Purity Germanium detector, low background, and Personal computer multichannel analyzer. Results: In Aswan Governorate, the mean specific activities of radionuclide's (226Ra, 232Th and 40K) 14.86, 13.78 and 175.4 in Bq/kg respectively. In Qena Governorate, the mean specific activities of mentioned radionuclides were 14.44 Bq/kg, 15.02 Bq/kg and 197.57 Bq/kg, respectively. These values were18.53 Bq/kg, 11.3 Bq/kg and 184.73 Bq/kg in Sohag Governorate, respectively. In Asyut Governorate the mean specific activities of the radionuclide's were 11.38 Bq/kg, 10.0 Bq/kg, and 164.715 Bq/kg, respectively. However, these values were 19.56 Bq/kg, 11.72 Bq/kg, and 239.92 Bq/kg in Minya Governorate, respectively. The hazard indices of gamma radiation such as Absorbed dose rate, annual effective dose equivalent and excess lifetime cancer risk were calculated. Conclusion: According to the results, all the values were within the reported values by the United Nations Scientific Committee on the Effects of Atomic Radiation. In addition, there was no likelihood of radiological health hazards to the population living close to the Nile river. © 2019, Mashhad University of Medical sciences.

关键词： Gamma rays

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DarSIA: An open-source Python toolbox for two-scale image processing of dynamics in porous media

arXiv

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arXiv 2023年

作者： Nordbotten, Jan Martin Benali, Benyamine Both, Jakub Wiktor Brattekås, Bergit Storvik, Erlend Fernø, Martin A. Center for Modeling of Coupled Subsurface Dynamics Dept. of Mathematics University of Bergen Norway Norwegian Research Center Postboks 22 Nygårdstangen Bergen5838 Norway Department of Physics and Technology University of Bergen Norway Department of Computer science Electrical engineering and Mathematical sciences Western Norway University of Applied Sciences Norway

Understanding porous media flow is inherently a multi-scale challenge, where at the core lies the aggregation of pore-level processes to a continuum, or Darcy-scale, description. This challenge is directly mirrored in image processing, where grains and interfaces may be clearly visible, yet continuous parameters are desirable to measure. Classical image processing is poorly adapted to this setting, as most techniques do not explicitly utilize the fact that the image contains explicit physical processes. Here, we adapt classical image processing concepts to what we define as "physical images" of porous materials and processes within them. This is realized through the development of a new open-source image analysis toolbox specifically adapted to time-series of images of porous materials. © 2023, CC BY.

关键词： Porous materials

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Bright-dark pulses in coupled ring lasers

Bright-dark pulses in coupled ring lasers

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CLEO: Fundamental science, CLEO:FS 2024 - Part of Conference on Lasers and Electro-Optics, CLEO 2024

作者： Letsou, Theodore P. Kazakov, Dmitry Ratra, Pawan Columbo, Lorenzo L. Cin, Sandro Dal Opacak, Nikola Piccardo, Marco Schwarz, Benedikt Capasso, Federico Harvard John A. Paulson School of Engineering and Applied Sciences Harvard University CambridgeMA02138 United States Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology CambridgeMA02139 United States Department of Electrical and Electronic Engineering Imperial College London Exhibition Rd South Kensington LondonSW7 2BX United Kingdom Dipartimento di Elettronica e Telecomunicazioni Politecnico di Torino Torino10129 Italy Institute of Solid State Electronics TU Wien Vienna1040 Austria Department of Physics Instituto Superior Técnico Universidade de Lisboa Lisbon1049-001 Portugal

Coupling semiconductor laser together unlocks new optical states unstable in uncoupled lasers. Here, we present one such state which manifests itself as a pair of bright and dark optical pulses. © 2024 The Author... 详细信息

ISBN: (纸本)9781957171395

关键词： Ring lasers

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Optical and photoluminescence modulation in monolayer molybdenum sulfide thin films via electrochemical deposition: Exploring the influence of deposition voltage and time

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Results in physics 2024年 61卷

作者： Ajayeoba, Yetunde A. Adewinbi, Saheed A. Akinrinola, Olusola Akande, Akinlolu Pillai, Suresh C Awodugba, Ayodeji O. Department of Physics Faculty of Basic and Applied Sciences College of Science Engineering and Technology Osun State University P.M.B 4494 Osun State Osogbo Nigeria Department of Pure and Applied Physics Ladoke Akintola University of Technology Ogbomosho P.M.B 4000 Oyo State Ogbomosho Nigeria Nanotechnology and Bio-Engineering Research Group Department of Environmental Science Faculty of Science Atlantic Technological University ATU Sligo Ash Lane Sligo F91 YW50 Ireland Instituto de Fisica Facultad de Fisica Pontificia Universidad Catolica de Chile Santiago 7820436 Chile Centre for Mathematical Modelling and Intelligent Systems for Health and Environment (MISHE) Atlantic Technological University Ash Lane Ballytivnan Sligo F91 YW50 Ireland

Monolayer Molybdenum Disulfide (MoS2) exhibits a direct bandgap characterized by strong visible photoluminescence, high on/off ratio, high optical transparency, low dissipation rate, and light absorption in a wide ene... 详细信息

Monolayer Molybdenum Disulfide (MoS₂) exhibits a direct bandgap characterized by strong visible photoluminescence, high on/off ratio, high optical transparency, low dissipation rate, and light absorption in a wide energy spectrum. The influence of different deposition voltages and durations on the optical and photoluminescent characteristics was investigated using Raman spectroscopy, UV–visible spectrophotometry, and photoluminescence spectroscopy. All samples were analyzed for optical properties to confirm their suitability for optoelectronics. The energy band gap and Urbach energy (band tail width) of all films were 1.87 to 2.52 eV and 0.31 to 0.49 eV, respectively. The findings reveal a correlation between enhanced absorption properties and a decrease in the bandgap of the semiconducting film layers, implying the potential utility of the deposited films as efficient solar absorbers. Furthermore, the improved transmittance observed within the visible wavelength range suggests their applicability as effective window layers in thin-film photodiodes. It was established that varying the voltage and time of deposition alone can enhance the optoelectronic performance of the material in any device. © 2024 The Author(s)

关键词： 2D-MoS2 Deposition potential Deposition time Electrodeposition Optical properties Photoluminescence

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High-Order Isogeometric Methods for Compressible Flows: I: Scalar Conservation Laws 19th

High-Order Isogeometric Methods for Compressible Flows: I: S...

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19th International Conference on Finite Elements in Flow Problems, FEF 2017

作者： Jaeschke, Andrzej Möller, Matthias Institute of Turbomachinery Lódź University of Technology Lódź Poland Faculty of Electrical Engineering Mathematics and Computer Science Delft Institute of Applied Mathematics Delft University of Technology Delft Netherlands

ISBN: (纸本)9783030307042

Isogeometric analysis was applied very successfully to many problem classes like linear elasticity, heat transfer and incompressible flow problems but its application to compressible flows is very rare. However, its ability to accurately represent complex geometries used in industrial applications makes IGA a suitable tool for the analysis of compressible flow problems that require the accurate resolution of boundary layers. The convection-diffusion solver presented in this chapter, is an indispensable step on the way to developing a compressible solver for complex viscous industrial flows. It is well known that the standard Galerkin finite element method and its isogeometric counterpart suffer from spurious oscillatory behaviour in the presence of shocks and steep solution gradients. As a remedy, the algebraic flux correction paradigm is generalized to B-Spline basis functions to suppress the creation of oscillations and occurrence of non-physical values in the solution. This work provides early results for scalar conservation laws and lays the foundation for extending this approach to the compressible Euler equations in the next chapter. © Springer Nature Switzerland AG 2020.

关键词： Compressible flow

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Computational Characterization of the Recently Synthesized Pristine and Porous 12-Atom-Wide Armchair Graphene Nanoribbon

arXiv

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arXiv 2025年

作者： da Gomes, Djardiel S. Felix, Isaac M. Radel, Willian F. Dias, Alexandre C. Ribeiro Junior, Luiz A. Pereira Junior, Marcelo L. State University of Campinas Gleb Wataghin Institute of Physics Department of Applied Physics Campinas São Paulo13083-859 Brazil University of Brasília Faculty UnB Planaltina Materials Science Postgraduate Program Federal District Brasília Brazil Center for Agri-food Science and Technology Federal University of Campina Grande Paraíba Pombal58840-000 Brazil University of Brasília Institute of Physics Physics Postgraduate Program Federal District Brasília70910900 Brazil Institute of Physics International Center of Physics University of Brasília Federal District Brasília70910-900 Brazil Institute of Physics University of Brasília Federal District Brasília70910-900 Brazil Computational Materials Laboratory University of Brasília Federal District Brasília70910900 Brazil University of Brasília College of Technology Department of Electrical Engineering Federal District Brasília70910-900 Brazil

Recently synthesized Porous 12-Atom-Wide Armchair Graphene Nanoribbons (12-AGNRs) [Nano Lett. 2024, 24, 10718-10723]exhibit tunable properties through periodic porosity, enabling precise control over their electronic, optical, thermal, and mechanical behavior. This work presents a comprehensive theoretical characterization of pristine and porous 12-AGNRs based on density functional theory (DFT) and molecular dynamics (MD) simulations. DFT calculations reveal substantial electronic modifications, including band gap widening and the emergence of localized states. Analyzed within the Bethe–Salpeter equation (BSE) framework, optical properties highlight strong excitonic effects and significant absorption shifts. Thermal transport simulations indicate a pronounced reduction in conductivity due to enhanced phonon scattering at nanopores. At the same time, MD-based mechanical analysis shows decreased stiffness and strength while maintaining structural integrity. Despite these modifications, porous 12-AGNRs remain mechanically and thermally stable. These findings establish porosity engineering as a powerful strategy for tailoring graphene nanoribbons’ functional properties, reinforcing their potential for nanoelectronic, optoelectronic, and thermal management *** Codes 00-xx © 2025, CC BY.

关键词： Nanoribbons

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Sub-kpc scale gas density histogram of the Galactic molecular gas: a new statistical method to characterise galactic-scale gas structures

arXiv

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arXiv 2024年

作者： Matsusaka, Ren Handa, Toshihiro Fujimoto, Yusuke Murase, Takeru Hirata, Yushi Nishi, Junya Ito, Takumi Sasaki, Megumi Mizoguchi, Tomoki Department of Physics and Astronomy Graduate School of Science and Engineering Kagoshima University 1-21-35 Korimoto Kagoshima Kagoshima890-0065 Japan Amanogawa Galaxy Astronomy Research Center Kagoshima University 1-21-35 Korimoto Kagoshima Kagoshima890-0065 Japan Department of Computer Science and Engineering University of Aizu Tsuruga Ikki-machi Aizu-Wakamatsu Fukushima965-8580 Japan Faculty of Engineering Gifu University 1-1 Yanagido Gifu501-1193 Japan Graduate School of Science and Technology Kumamoto University Kumamoto860-8555 Japan

To understand physical properties of the interstellar medium (ISM) on various scales, we investigate it at parsec resolution on the kiloparsec scale. Here, we report on the sub-kpc scale Gas Density Histogram (GDH) of the Milky Way. The GDH is a density probability distribution function (PDF) of the gas volume density. Using this method, we are free from an identification of individual molecular clouds and their spatial structures. We use survey data of 12CO and 13CO (J=1-0) emission in the Galactic plane (I = 10◦-50◦) obtained as a part of the FOREST Unbiased Galactic plane Imaging survey with the Nobeyama 45m telescope (FUGIN). We make a GDH for every channel map of 2◦ × 2◦ area including the blank sky component, and without setting cloud boundaries. This is a different approach from previous works for molecular clouds. The GDH fits well to a single or double log-normal distribution, which we name the low-density log-normal (L-LN) and high-density log-normal (H-LN) components, respectively. The multi-log-normal components suggest that the L-LN and H-LN components originate from two different stages of structure formation in the ISM. Moreover, we find that both the volume ratios of H-LN components to total (fH) and the width of the L-LN along the gas density axis (σL) show coherent structure in the Galactic-plane longitude-velocity diagram. It is possible that these GDH parameters are related to strong galactic shocks and other weak shocks in the Milky Way. © 2024, CC BY.

关键词： Density of gases

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A study on managing plastic waste to tackle the worldwide plastic contamination and environmental remediation

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Chemosphere 2023年第1期341卷 139979页

作者： Priya, A.K. Muruganandam, M. Imran, Muhammad Gill, Rana Vasudeva Reddy, Minnam Reddy Shkir, Mohd Sayed, M.A. AlAbdulaal, T.H. Algarni, H. Arif, Mohd Jha, Niraj Kumar Sehgal, Satbir S. Department of Chemical Engineering KPR Institute of Engineering and Technology Tamilnadu India Dehradun India Technology and Innovation Center Riyadh11551 Saudi Arabia University Centre for Research & Development Electronics & Communication Department Chandigarh University Gharuan Punjab Mohali India School of Chemical Engineering Yeungnam University Gyeongsa 38541 Korea Republic of Department of Physics Faculty of Science King Khalid University Abha61413 Saudi Arabia Applied Science and Humanities Section University Polytechnic Faculty of Engineering and Technology Jamia Millia Islamia New Delhi110025 India Department of Biotechnology School of Engineering and Technology Sharda University Greater Noida201310 India Division of Research Innovation Uttaranchal University Dehradun India

Over the past 50 years, the emergence of plastic waste as one of the most urgent environmental problems in the world has given rise to several proposals to address the rising levels of contaminants associated with plastic debris. Worldwide plastic production has increased significantly over the last 70 years, reaching a record high of 359 million tonnes in 2020. China is currently the world's largest plastic producer, with a share of 17.5%. Of the total marine waste, microplastics account for 75%, while land-based pollution accounts for responsible for 80–90%, and ocean-based pollution 10–20% only in overall pollution problems. Even at small dosages (10 μg/mL), microplastics have been found to cause toxic effects on human and animal health. This review examines the sources of microplastic contamination, the prevalent reaches of microplastics, their impacts, and the remediation methods for microplastic contamination. This review explains the relationship between the community composition and the presence of microplastic particulate matter in aquatic ecosystems. The interaction between microplastics and emerging pollutants, including heavy metals, has been linked to enhanced toxicity. The review article provided a comprehensive overview of microplastic, including its fate, environmental toxicity, and possible remediation strategies. The results of our study are of great value as they illustrate a current perspective and provide an in-depth analysis of the current status of microplastics in development, their test requirements, and remediation technologies suitable for various environments. © 2023 Elsevier Ltd

关键词： Heavy metals

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Detection of Diabetic Macular Edema in Retinal OCT Images with Firefly-Algorithm Selected Features 31

Detection of Diabetic Macular Edema in Retinal OCT Images wi...

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31st International Conference on computer Theory and Applications, ICCTA 2021

作者： Kadry, Seifedine Rajinikanth, Venkatesan Jerry, Jiny Mariam Gifta, R. Carolin Noroff University College Faculty of Applied Computing and Technology Kristiansand Norway St. Joseph's College of Engineering Omr Department of Electronics and Instrumentation Engineering Chennai600119 India St. Joseph's College of Engineering Omr Department of Computer Science and Engineering Chennai600119 India

ISBN: (纸本)9781665478540

In modern hospitals, computer algorithms are widely implemented to diagnose the disease in patients using the medical data collected using a recommended protocol. Recently, the diabetes is human group is gradually rising and the early stage can be predicted by screening the eye. Diabetic-Macular-Edema (DME) is one of the harsh diseases and the untreated disease will initiate various eye abnormalities including the vision loss. In clinics, the retinal image recorded with a chosen imaging system is considered to inspect the disease. In this work, Optical Coherence Tomography (OCT) images are considered for the assessment of the DME in the OCT images. The proposed scheme consist the following stages;(i) Image collection and resizing, (ii) Retinal section extraction using joint thresholding and segmentation, (iii) Feature extraction and dominant feature selection with Firefly-Algorithm, (iv) Binary classification and validation. In this work, 500 numbers of Normal/DME class images with pixel dimension 256 × 256 ×1 pixels are considered and a binary classification with a 5-fold cross validation is implemented. The proposed technique helped to get a detection accuracy of 95% with K-Nearest Neighbors (KNN) classifier. © 2021 IEEE.

关键词： Optical tomography

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On-chip pulse shaping of entangled photons

arXiv

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arXiv 2024年

作者： Wu, Kaiyi Cohen, Lucas M. Myilswamy, Karthik V. Lingaraju, Navin B. Lu, Hsuan-Hao Lukens, Joseph M. Weiner, Andrew M. Elmore Family School of Electrical and Computer Engineering Purdue Quantum Science and Engineering Institute Purdue University West LafayetteIN47907 United States The Johns Hopkins University Applied Physics Laboratory LaurelMD20723 United States Quantum Information Science Section Computational Sciences and Engineering Division Oak Ridge National Laboratory Oak RidgeTN37831 United States Research Technology Office and Quantum Collaborative Arizona State University TempeAZ85287 United States

We demonstrate spectral shaping of entangled photons with a six-channel microring-resonatorbased silicon photonic pulse shaper. Through precise calibration of thermal phase shifters in a microresonator-based pulse shaper, we demonstrate line-by-line phase control on a 3 GHz grid for two frequency-bin-entangled qudits, corresponding to Hilbert spaces of up to 6×6 (3×3) dimensions for shared (independent) signal-idler filters. The pulse shaper's fine spectral resolution enables control of nanosecond-scale temporal features, which are observed by direct coincidence detection of biphoton correlation functions that show excellent agreement with theory. This work marks, to our knowledge, the first demonstration of biphoton pulse shaping using an integrated spectral shaper and holds significant promise for applications in quantum information processing. Copyright © 2024, The Authors. All rights reserved.

关键词： Hilbert spaces

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