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Masekane MC, Msimanga M, Bogdanović Radović I, Madhuku M, Moloi SJ. Semi-empirical parameterization of HI/p L-shell X-ray production cross section ratios in Bi for Heavy Ion PIXE. Sci Rep 2023; 13:20942. [PMID: 38017034 PMCID: PMC10684581 DOI: 10.1038/s41598-023-48217-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Accepted: 11/23/2023] [Indexed: 11/30/2023] Open
Abstract
Quantitative analysis of materials from Heavy Ion PIXE spectra remains impeded by the lack of reliable X-ray production cross section (XPCS) data. Although efforts at experimental Heavy Ion induced XPCS measurements still continue, Multiple Ionisation (MI) effects, which are not fully described by theory, render simulations of heavy ion PIXE data unreliable for large Z1/Z2 collisions, especially at low energies. This is also exacerbated by the random selection of projectile-target combinations for measured and reported experimental data available to validate theory. This study explored heavy ion induced X-ray production cross section deviations from those induced by protons at the same ion velocity. This enabled evaluations of the degree to which cross sections are enhanced through MI effects, with the aim of predicting XPCS due to heavy ion impact. The evaluation was carried out through the scaling of experimental heavy ion to theoretical proton cross section ratios (R), which were then used for the interpolation of XPCS in the same target element for 'missing' projectiles within the range of evaluation. Here we present measurements of heavy ion induced total L-shell XPCS in Bi, carried out to determine HI/p MI induced deviations due to C, F, Cl and Ti projectiles at an ion velocity range of (0.2-1.0) MeV/nucleon.
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Affiliation(s)
- M C Masekane
- Department of Physics, University of South Africa, P Bag X90, Florida, 1710, South Africa.
- Department of Physics, University of Zagreb, Bijenićka C. 32, 10000, Zagreb, Croatia.
- Ruđer Bošković Institute, P.O. Box 1016, 10000, Zagreb, Croatia.
- iThemba LABS TAMS, National Research Foundation, P Bag 11, WITS, Johannesburg, 2050, South Africa.
| | - M Msimanga
- iThemba LABS TAMS, National Research Foundation, P Bag 11, WITS, Johannesburg, 2050, South Africa
- Physics Department, Tshwane University of Technology, P Bag X680, Pretoria, 0001, South Africa
| | | | - M Madhuku
- iThemba LABS TAMS, National Research Foundation, P Bag 11, WITS, Johannesburg, 2050, South Africa
| | - S J Moloi
- Department of Physics, University of South Africa, P Bag X90, Florida, 1710, South Africa
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Abdul Razak NE, Dee CF, Madhuku M, Ahmad I, Chang EY, Yu HW, Majlis BY, Berhanuddin DD. Role of Boron in Assisting the Super-Enhancement of Emissions from Carbon-Implanted Silicon. Materials (Basel) 2023; 16:2070. [PMID: 36903185 PMCID: PMC10004110 DOI: 10.3390/ma16052070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 01/25/2023] [Accepted: 02/08/2023] [Indexed: 06/18/2023]
Abstract
The super enhancement of silicon band edge luminescence when co-implanted with boron and carbon is reported. The role of boron in the band edge emissions in silicon was investigated by deliberately introducing defects into the lattice structures. We aimed to increase the light emission intensity from silicon by boron implantation, leading to the formation of dislocation loops between the lattice structures. The silicon samples were doped with a high concentration of carbon before boron implantation and then annealed at a high temperature to activate the dopants into substitutional lattice sites. Photoluminescence (PL) measurements were performed to observe the emissions at the near-infrared region. The temperatures were varied from 10 K to 100 K to study the effect of temperature on the peak luminescence intensity. Two main peaks could be seen at ~1112 and 1170 nm by observing the PL spectra. The intensities shown by both peaks in the samples incorporated with boron are significantly higher than those in pristine silicon samples, and the highest intensity in the former was 600 times greater than that in the latter. Transmission electron microscopy (TEM) was used to study the structure of post-implant and post-anneal silicon sample. The dislocation loops were observed in the sample. Through a technique compatible with mature silicon processing technology, the results of this study will greatly contribute to the development of all Si-based photonic systems and quantum technologies.
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Affiliation(s)
- Nurul Ellena Abdul Razak
- Institute of Microengineering and Nanoelectronics (IMEN), Universiti Kebangsaan Malaysia (UKM), Bangi 43600, Malaysia
| | - Chang Fu Dee
- Institute of Microengineering and Nanoelectronics (IMEN), Universiti Kebangsaan Malaysia (UKM), Bangi 43600, Malaysia
| | - Morgan Madhuku
- iThemba Laboratory for Accelerator Based Science (LABS), Johannesburg 2050, South Africa
| | - Ishaq Ahmad
- NPU-NCP Joint International Research Center on Advanced Nanomaterials and Defect Engineering, National Centre for Physics, Islamabad 44000, Pakistan
| | - Edward Yi Chang
- Department of Materials Science and Engineering, National Yang-Ming Chiao-Tung University, Hsinchu 30010, Taiwan
- Department of Electronic Engineering, International College of Semiconductor Technology, National Yang-Ming Chiao-Tung University, Hsinchu 30010, Taiwan
| | - Hung Wei Yu
- Department of Materials Science and Engineering, National Yang-Ming Chiao-Tung University, Hsinchu 30010, Taiwan
- Department of Electronic Engineering, International College of Semiconductor Technology, National Yang-Ming Chiao-Tung University, Hsinchu 30010, Taiwan
| | - Burhanuddin Yeop Majlis
- Institute of Microengineering and Nanoelectronics (IMEN), Universiti Kebangsaan Malaysia (UKM), Bangi 43600, Malaysia
| | - Dilla Duryha Berhanuddin
- Institute of Microengineering and Nanoelectronics (IMEN), Universiti Kebangsaan Malaysia (UKM), Bangi 43600, Malaysia
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Abdul Razak NE, Madhuku M, Ahmad I, Majlis BY, Chang FD, Berhanuddin DD. Structural and Photoluminescence Analysis on the Implantation of Carbon and Proton for the Creation of Damage-Assisted Emission in Silicon. SAINS MALAYS 2020. [DOI: 10.17576/jsm-2020-4912-06] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
We study the induced defects in the depth profiling of the silicon structure after being implanted with carbon and followed by high energy proton irradiation. It has been reported before that the formation of the optically active point-defect, specifically the G-centre is due to the implantation and irradiation of carbon and proton, respectively. It is crucial to quantify the diffusional broadening of the implanted ion profile especially for proton irradiation process so that the radiation damage evolution can be maximized at the point-defect formation region. Profiling analysis was carried out using computational Stopping and Range of Ions in Matter (SRIM) and Surrey University Sputter Profile Resolution from Energy Deposition (SUSPRE) simulation. The energies of carbon ions adopted for this investigation are 10, 20, 30, and 50 keV, while proton irradiation energy was kept at 2 MeV. Photoluminescence measurements on silicon implanted with carbon at different energies were carried out to study the interrelation between the numbers of vacancies produced during the damage event and the peak emission intensities.
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Masekane M, Moloi S, Madhuku M, Msimanga M. Measurement of 12Cq+ and 35Clq+ ion induced X-ray production cross sections in V, Zr and Sn metal oxide films at 0.1 MeV/u - 1.0 MeV/u energies. Radiat Phys Chem Oxf Engl 1993 2020. [DOI: 10.1016/j.radphyschem.2020.109083] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Singh K, Wamwangi D, Mathe B, Billing D, Madhuku M. Minimum lattice thermal conductivity of In 3SbTe 2 by surface Brillouin scattering. J Opt Soc Am A Opt Image Sci Vis 2020; 37:C132-C137. [PMID: 33175742 DOI: 10.1364/josaa.399149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 08/11/2020] [Indexed: 06/11/2023]
Abstract
Phase-change materials are chalcogenide alloys used for nonvolatile memory applications due to their rapid and reversible structural transformation. In3SbTe2 is a promising candidate that exhibits transitions dependent on thermal conductivity. The minimum lattice thermal conductivity of amorphous In3SbTe2 is investigated by surface acoustic propagation. In3SbTe2 thin films were deposited by radio frequency magnetron sputtering on (100) Si. Rutherford backscattering spectrometry and x-ray reflectivity were used to establish the elemental composition, deposition rate, and mass density. Using the Debye model, the thermal conductivity is extracted from fitted phase velocities measured by surface Brillouin scattering. The low thermal conductivity is revealed to be suitable for Joule heating.
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Kamunda C, Mathuthu M, Madhuku M. Health Risk Assessment of Heavy Metals in Soils from Witwatersrand Gold Mining Basin, South Africa. Int J Environ Res Public Health 2016; 13:E663. [PMID: 27376316 PMCID: PMC4962204 DOI: 10.3390/ijerph13070663] [Citation(s) in RCA: 184] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Revised: 05/26/2016] [Accepted: 06/28/2016] [Indexed: 12/01/2022]
Abstract
The study evaluates the health risk caused by heavy metals to the inhabitants of a gold mining area. In this study, 56 soil samples from five mine tailings and 17 from two mine villages were collected and analyzed for Asernic (As), Lead (Pb), Mercury (Hg), Cadmium (Cd), Chromium (Cr), Cobalt (Co), Nickel (Ni), Copper (Cu) and Zinc (Zn) using ICP-MS. Measured concentrations of these heavy metals were then used to calculate the health risk for adults and children. Their concentrations were such that Cr > Ni > As > Zn > Cu > Co > Pb > Hg > Cd, with As, Cr and Ni higher than permissible levels. For the adult population, the Hazard Index value for all pathways was found to be 2.13, making non-carcinogenic effects significant to the adult population. For children, the Hazard Index value was 43.80, a value >>1, which poses serious non-carcinogenic effect to children living in the gold mining area. The carcinogenic risk was found to be 1.7 × 10(-4) implying that 1 person in every 5882 adults may be affected. In addition, for children, in every 2725 individuals, 1 child may be affected (3.67 × 10(-4)). These carcinogenic risk values were both higher than acceptable values.
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Affiliation(s)
- Caspah Kamunda
- Center for Applied Radiation Science and Technology, North West University (Mafikeng), Private Bag X2046, Mmabatho 2735, South Africa.
| | - Manny Mathuthu
- Center for Applied Radiation Science and Technology, North West University (Mafikeng), Private Bag X2046, Mmabatho 2735, South Africa.
| | - Morgan Madhuku
- iThemba LABS, National Research Foundation, Private Bag X11, Wits 2050, South Africa.
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Mathuthu M, Kamunda C, Madhuku M. Modelling of Radiological Health Risks from Gold Mine Tailings in Wonderfonteinspruit Catchment Area, South Africa. Int J Environ Res Public Health 2016; 13:E570. [PMID: 27338424 PMCID: PMC4924027 DOI: 10.3390/ijerph13060570] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Revised: 05/27/2016] [Accepted: 06/03/2016] [Indexed: 11/16/2022]
Abstract
Mining is one of the major causes of elevation of naturally-occurring radionuclide material (NORM) concentrations on the Earth's surface. The aim of this study was to evaluate the human risk associated with exposure to NORMs in soils from mine tailings around a gold mine. A broad-energy germanium detector was used to measure activity concentrations of these NORMs in 66 soil samples (56 from five mine tailings and 10 from the control area). The RESidual RADioactivity (RESRAD) OFFSITE modeling program (version 3.1) was then used to estimate the radiation doses and the cancer morbidity risk of uranium-238 ((238)U), thorium-232 ((232)Th), and potassium-40 ((40)K) for a hypothetical resident scenario. According to RESRAD prediction, the maximum total effective dose equivalent (TEDE) during 100 years was found to be 0.0315 mSv/year at year 30, while the maximum total excess cancer morbidity risk for all the pathways was 3.04 × 10(-5) at year 15. The US Environmental Protection Agency considers acceptable for regulatory purposes a cancer risk in the range of 10(-6) to 10(-4). Therefore, results obtained from RESRAD OFFSITE code has shown that the health risk from gold mine tailings is within acceptable levels according to international standards.
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Affiliation(s)
- Manny Mathuthu
- Center for Applied Radiation Science and Technology, North West University (Mafikeng), P.Bag X2046, Mmabatho 2735, South Africa.
| | - Caspah Kamunda
- Center for Applied Radiation Science and Technology, North West University (Mafikeng), P.Bag X2046, Mmabatho 2735, South Africa.
| | - Morgan Madhuku
- iThemba LABS, National Research Foundation, Private Bag X11, WITS 2050, South Africa.
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Kamunda C, Mathuthu M, Madhuku M. An Assessment of Radiological Hazards from Gold Mine Tailings in the Province of Gauteng in South Africa. Int J Environ Res Public Health 2016; 13:E138. [PMID: 26797624 PMCID: PMC4730529 DOI: 10.3390/ijerph13010138] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Revised: 01/09/2016] [Accepted: 01/14/2016] [Indexed: 11/17/2022]
Abstract
Radiological hazards associated with exposure to Naturally Occurring Radionuclides Materials from gold mine tailings in the province of Gauteng in South Africa were evaluated. A comparison was made with soil samples from a control area. In this study, gamma spectroscopy was used to measure the activity concentrations of these radionuclides in 56 soil samples from the mine tailings and 10 soil samples from the control area. The average activity concentrations in Bq∙kg(-1) for Uranium-238, Thorium-232, and Potassium-40 from the mine tailings were found to be 785.3 ± 13.7, 43.9 ± 1.0 and 427.0 ± 13.1, respectively. On the other hand, the average activity concentrations in Bq∙kg(-1) for Uranium-238, Thorium-232, and Potassium-40 from the control area were found to be 17.0.1 ± 0.4, 22.2 ± 0.5 and 496.8 ± 15.2, respectively. Radiological hazard parameters calculated from these activity concentrations were higher than recommended safe limits. In particular, calculated average values for the external hazard (Hex) and the internal hazard (Hin) from the mine tailings were found to be 2.4 and 4.5. Both these values were higher than unity, posing a significant health risk to the population in the area.
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Affiliation(s)
- Caspah Kamunda
- Center for Applied Radiation Science and Tehnology, North West University (Mafikeng), P.Bag X2046, Mmabatho 2735, South Africa.
| | - Manny Mathuthu
- Center for Applied Radiation Science and Tehnology, North West University (Mafikeng), P.Bag X2046, Mmabatho 2735, South Africa.
| | - Morgan Madhuku
- iThemba LABS, National Research Foundation, Private Bag X11, WITS 2050, South Africa.
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Akram W, Madhuku M, Ahmad I, Xiaolin L, Zhang G, Yan L. Morphology, microstructure and chemical composition of single inhalable particles in Shanghai, China. Environ Monit Assess 2014; 186:8587-8598. [PMID: 25252792 DOI: 10.1007/s10661-014-4026-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Accepted: 08/25/2014] [Indexed: 06/03/2023]
Abstract
The morphology, microstructure, and chemical composition of a variety of particles emitted from coal-fired power plants, steel plants, and vehicle exhausts, which are possible sources of particulate matter (PM) in the atmosphere, were investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) and compared with particle samples collected from urban atmosphere to identify the best footprint or the suitable indicator relating the existence of studied particles and their possible emitters by the morphology, microstructure, and chemical composition of the particles. The investigation indicated that the particles from these three sources are different in morphology, microstructure, and chemical composition. Sphere aggregates were generally the most abundant components, with silicon and aluminum as major elements. The urban air particulate contained particles similar to those observed in the power plant, steel plant, and vehicle exhaust samples suggesting that all three sources are contributing to the pollution in the city.
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Affiliation(s)
- Waheed Akram
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, 201800, China
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