Article
Environmental Sciences
Dhinesh Sugumaran, William H. Blake, Geoffrey E. Millward, Zulkifli Yusop, Abdull Rahim Mohd Yusoff, Nur Athirah Mohamad, Anand Nainar, Kogila Vani Annammala
Summary: Pristine tropical river systems are facing increasing pressure from economic resource development such as forestry and mining. The Lebir catchment in north eastern Malaysia is undergoing development due to unregulated tree felling and mining. Research suggests that contaminants are being transported by major rivers and contaminating riverine floodplains, highlighting the need for a more integrated approach to maintain the environmental quality of these fragile aquatic systems.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2023)
Article
Environmental Sciences
Cristiano Cigagna, Daniel Marcos Bonotto, Antonio F. Monteiro Camargo
Summary: The study of sedimentation rate in five cores from the Itanhaem watershed in the state of Sao Paulo, Brazil, using the lead-210 radioisotope revealed a historical variation in sedimentation rate. The waters and sediments of the rivers were analyzed to support geochronological analysis results and associate sediments with possible source areas. The study found a longitudinal salinity gradient in the downstream river courses, with a predominance of certain ions in the waters and silica as the predominant constituent in the sediment cores, inversely related to organic matter presence.
ENVIRONMENTAL MONITORING AND ASSESSMENT
(2021)
Article
Engineering, Environmental
H. N. Hunter, C. J. B. Gowing, A. L. Marriott, J. H. Lacey, S. Dowell, M. J. Watts
Summary: This communication presents a validation approach using varve counting to improve the accuracy of Pb-210 measurement data and generate more precise chronologies. This is crucial for predicting environmental changes such as sedimentation rates, climate change, pollution pathways, and land degradation.
ENVIRONMENTAL GEOCHEMISTRY AND HEALTH
(2023)
Article
Environmental Sciences
Sonam Priyadarshini Rout, Sivaprakasam Vasudevan
Summary: The pristine Himalayan Wetlands are facing endangerment due to increased sedimentation rate and anthropogenic encroachment. Human interference has resulted in faster sedimentation in recent years.
ENVIRONMENTAL MONITORING AND ASSESSMENT
(2022)
Article
Environmental Sciences
Krishna Kumar Singh, Sivaprakasam Vasudevan
Summary: This study presents initial information on the sedimentation rate estimation for Lake Pykara. It utilized Cs-137 and Pb-210(ex) analysis to establish a chronological sequence of sediment core, determining an average sedimentation rate of 0.71 cm year(-1) and estimated the age of the lake to be around 514.08 years to 521.43 years.
ENVIRONMENTAL MONITORING AND ASSESSMENT
(2021)
Article
Engineering, Civil
Hui Bai, Yan Chen, Yonggui Wang, Zhen Song, Hongjin Tong, Yao Wei, Qing Yu, Ziyi Xu, Shuihua Yang
Summary: The study developed a water pollution sources apportionment and contribution rates analysis method based on a one-dimensional model, finding that urban living point sources contributed most to COD and NH4+-N pollution, while agricultural sources were the main pollution source of TP. Contribution rates change along with precipitation variability in different seasons and water periods, encouraging the tracing of environmental responsibility subjects.
JOURNAL OF HYDROLOGY
(2021)
Article
Meteorology & Atmospheric Sciences
Weslley de Brito Gomesa, Prakki Satyamurty, Francis Wagner Silva Correia, Sin Chan Chou, Leonardo Alves Vergasta, Andre de Arruda Lyra
Summary: This study used the Eta Regional Model for dynamic downscaling at a 30-day scale and found that the ensemble mean had good skill and reproduced the seasonal and spatial distribution of hydrological variables. Members using the Betts-Miller-Janjic relaxation technique performed the best.
ATMOSPHERIC RESEARCH
(2022)
Article
Geosciences, Multidisciplinary
Jose Reinaldo Cardoso Nery, Daniel Marcos Bonotto
Summary: This study evaluates the sedimentation rates in the Amazon River mouth by analyzing the activity profiles of excess 210Pb in sediment cores. The Geoaccumulation Index (Igeo) calculated from chemical data indicates that the environment is practically unpolluted despite mining activities. The apparent sediment mass accumulation rates are consistent with previous studies.
JOURNAL OF SOUTH AMERICAN EARTH SCIENCES
(2022)
Article
Computer Science, Interdisciplinary Applications
Lizandra Broseghini Foeger, Diogo Costa Buarque, Paulo Rogenes Monteiro Pontes, Hugo de Oliveira Fagundes, Fernando Mainardi Fan
Summary: This study compares the results generated by different flow routing approaches in large-scale erosion and sediment transport models and evaluates the sediment characteristics. The simulation with the inertial approach shows similar results to other methods and has simpler preprocessing and numerical features.
ENVIRONMENTAL MODELLING & SOFTWARE
(2022)
Article
Environmental Sciences
Melissa S. Barbosa, Dario P. Carvalho, Waleska Gravena, Ronaldo de Almeida, Marilia H. Mussy, Eduardo A. Sousa, Igor B. B. Holanda, Izidro F. de Sousa-Filho, Wanderley R. Bastos
Summary: The study evaluated the exposure of river dolphins in the Amazon to methylmercury (MeHg) and total mercury (THg), with findings showing significantly higher THg and MeHg concentrations in adult dolphins compared to calves, while no significant differences were observed between genders at different sampling locations. The mercury exposure in dolphins is derived from the consumption of fish species with different feeding habits.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2021)
Review
Environmental Sciences
J. M. Abril-Hernandez
Summary: This study comprehensively reviews the existing mathematical models based on the 210Pb method and evaluates their performance. The PLUM model was found to not produce reliable chronologies in any of the studied cores, while the CRS model is too sensitive to accurate estimation of total inventory. The CFCS model with least squares fitting and the x-CF models performed the best under common sedimentary conditions.
JOURNAL OF ENVIRONMENTAL RADIOACTIVITY
(2023)
Article
Water Resources
Leonardo Alves Vergasta, Francis Wagner Silva Correia, Prakki Satyamurty, Sin Chan Chou, Andre de Arruda Lyra, Weslley de Brito Gomes, Ayan Fleischmann, F. Papa
Summary: This study evaluates the performance of a regional climate model (Eta) and a large-scale hydrological model (MGB) in representing hydroclimatic variables in the Madeira River basin. The results show that the Eta model underestimates (overestimates) precipitation during the rainy (dry) season. The MGB model simulates hydrological processes satisfactorily, though it has limitations in timing floods and their removal in different discharge regimes.
HYDROLOGICAL SCIENCES JOURNAL
(2023)
Article
Environmental Sciences
Balamurugan Palani, Sivaprakasam Vasudevan, Thirunavukkarasu Ramkumar, Selvaganapathi Rajendiran, Sathyamoorthy Gunasekaran
Summary: This study used natural and anthropogenic radiometric dating techniques to determine sedimentation rates and the age of Kodaikanal Lake. The findings show that the sedimentation rate of the lake is 0.51 cm/year with a core age of 86 years. The study also analyzed the sediment composition and grain size.
ENVIRONMENTAL EARTH SCIENCES
(2023)
Article
Chemistry, Analytical
D. M. Bonotto, T. P. P. Sabaris, D. C. Bicudo, C. E. M. Bicudo, L. Fontana
Summary: The Constant Flux: Constant Sedimentation (CF:CS) and Constant Rate of Supply (CRS) models were applied to a Pb-210 dataset from two sediment profiles (GUA-T1 and GUA-T2) sampled at Guarapiranga reservoir in Sao Paulo, Brazil. The CF:CS model yielded sedimentation rates of 9.3-12.3 and 30 mg.cm(-2)yr(-1) for GUA-T1 and GUA-T2 profiles, respectively, showing better chronological performance compared to the CRS model in the study area and allowing successful estimation of phosphorus fluxes in the reservoir.
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
(2022)
Article
Environmental Sciences
J. M. Abril-Hernandez
Summary: The Pb-210-based method is used to determine the absolute age of recent sediments on the centennial scale. The CSAR model captures the sedimentation rate and provides reliable chronologies and paleorecords of A(o), which are useful for tracking past changes in sedimentary conditions.
JOURNAL OF ENVIRONMENTAL RADIOACTIVITY
(2023)
Article
Chemistry, Inorganic & Nuclear
R. Galea, K. Moore
Summary: In this study, the solution of 225Ac was standardized using the TDCR method. The counting efficiencies were calculated to be approximately 500% for the NRC TDCR system. The relative uncertainty for the activity concentration was determined to be 0.25%. The measured half-life of 225Ac was found to be consistent with previous measurements.
APPLIED RADIATION AND ISOTOPES
(2024)
Article
Chemistry, Inorganic & Nuclear
N. C. Ramirez, S. M. Collins
Summary: In this paper, the authors determined the half-life of 68Ga using ionisation chambers measurements and HPGe gamma-ray spectrometry. They reviewed the current literature and identified possible causes of inconsistency within the dataset. The findings suggest that addressing these issues could lead to a significant improvement in future evaluations of the half-life.
APPLIED RADIATION AND ISOTOPES
(2024)
Article
Chemistry, Inorganic & Nuclear
C. P. Mano, C. Chapelle, Der Mesrobian Kabakian, H. Paradis, O. Delaune, L. Patryl
Summary: CEA/DAM is developing new beta-gamma measurement systems to enhance the reliability of the Comprehensive Nuclear Test Ban Treaty's verification regime. A new spectral unmixing algorithm for full-spectrum analysis was tested to improve analysis methods for nuclear activities with low statistics.
APPLIED RADIATION AND ISOTOPES
(2024)
Article
Chemistry, Inorganic & Nuclear
Junyoung Lee, Geunsub Kim, Hyegang Chang, Sangmin Lee, Sung-Joon Ye
Summary: The study applied the convolution/superposition method to calculate the dose distribution of boron neutron capture therapy and compared it with the Monte Carlo method. The results showed that the C/S method has a fast calculation speed and reasonable accuracy.
APPLIED RADIATION AND ISOTOPES
(2024)
Article
Chemistry, Inorganic & Nuclear
Victor H. Elvira, Marie-Christine Lepy, Yves Menesguen, Stephanie Melhem
Summary: In this study, a cryogenic electrical-substitution radiometer was utilized for the primary calibration of monochromatic photon beams at a synchrotron facility, in order to determine the intrinsic efficiency and dead layer thickness of an HPGe detector. This calibration method allowed for the calculation of efficiency up to 55 keV, where the active thickness of the detector is not a determining factor. Geometrical efficiency was also determined through measurements of a radioactive source at various distances.
APPLIED RADIATION AND ISOTOPES
(2024)
Article
Chemistry, Inorganic & Nuclear
Ali Pashazadeh, Hamid Reza Baghani, Mostafa Robatjazi, Prajit Kadavil
Summary: This study investigated the effect of patch source geometric parameters on the depth dose distribution in skin tissue through Monte Carlo simulation. The results showed that increasing the source-to-skin distance, patch thickness, and patch diameter will reduce the depth dose distribution, with the source-to-skin distance having the most significant impact on dose gradient.
APPLIED RADIATION AND ISOTOPES
(2024)
Article
Chemistry, Inorganic & Nuclear
Yueli Song, Fengqun Zhou, Yajuan Hao, Xiaopeng Zhang, Pengfei Ji, Yong Li
Summary: In this study, the cross section values of the 109Ag(n,2n)108mAg reaction at different neutron energies were measured using the activation technique and off-line gamma-ray spectrometry. The results were compared with experimental data, evaluated data from libraries, and theoretical values to validate their accuracy.
APPLIED RADIATION AND ISOTOPES
(2024)
Article
Chemistry, Inorganic & Nuclear
Zhongkai Fan, Tao Hu, Xiangming Cai, Ruomei Xie, Haoxuan Li, Fengdi Qin, Shoukang Qiu, Yanliang Tan, Jian Shan
Summary: The high-precision measurement of Rn-220 is crucial for assessing and preventing thoron radiological hazards. By adding a ZnS(Ag)-coated clapboard, the issue of reduced Rn-220 concentrations due to decreased air pressure can be addressed, leading to improved detection efficiency. Experimental and simulation results provide valuable references for establishing the Rn-220 calibration factor.
APPLIED RADIATION AND ISOTOPES
(2024)
Article
Chemistry, Inorganic & Nuclear
R. Han, Z. Chen, Y. Nie, B. Liu, G. Tian, X. Zhang, F. Shi, H. Sun, Z. Zhang, Y. Ding, X. Ruan, J. Ren, S. Zhang
Summary: The leakage neutron spectra of Lead samples were measured using a TOF technique, and MCNP simulations with different nuclear data libraries showed that JENDL-5.0 and JEFF-3.3 libraries have better agreement with experimental data. Differences in spectra mainly stem from variations in neutron reaction channels across the libraries, with ENDF/B-VIII.0 and CENDL-3.2 libraries being overestimated in certain energy ranges.
APPLIED RADIATION AND ISOTOPES
(2024)
Article
Chemistry, Inorganic & Nuclear
Nissren Tamam, Maryam Al Huwayz, Z. A. Alrowaili, Norah Alwadai, Khadijah Mohammedsaleh Katubi, Mohammed S. Alqahtani, I. O. Olarinoye, M. S. Al-Buriahi
Summary: This study investigates the radiation shielding properties and radiation protection applications of borotellurite glasses. The results show that the addition of TeO2 can enhance the glass's ability to absorb photons and fast neutrons, and effectively suppress photon buildup. These glasses also exhibit exceptional gamma radiation and fast neutron moderating abilities, making them suitable for designing lead-free, transparent, and efficient radiation protection structures.
APPLIED RADIATION AND ISOTOPES
(2024)
Article
Chemistry, Inorganic & Nuclear
S. Chasapoglou, M. Kokkoris, R. Vlastou, M. Diakaki, V. Michalopoulou, A. Kalamara, G. Gkatis, A. Stamatopoulos, M. Axiotis, S. Harissopulos, A. Lagoyannis, M. I. Savva, T. Vasilopoulou, C. Lederer-Woods, N. Patronis, K. Kaperoni
Summary: This study investigated the accuracy and limitations of theoretical corrections in neutron-induced reactions on isotopically enriched Ge targets. Experimental cross-section measurements were conducted on several reactions using Ge-nat and isotopically enriched Ge targets. The results showed that the methodology using isotopically enriched targets provided accurate results without the need for theoretical corrections.
APPLIED RADIATION AND ISOTOPES
(2024)
Article
Chemistry, Inorganic & Nuclear
P. G. Konstantinidis, G. S. Polymeris, E. Tsoutsoumanos, G. Kitis
Summary: This study investigates an altered version of an existing protocol to study the mechanisms and phenomena of stimulated luminescence. The protocol allows for the examination of recombination mechanisms and trapping parameters of the traps, as well as the observation of potential transitions between two different states.
APPLIED RADIATION AND ISOTOPES
(2024)
Article
Chemistry, Inorganic & Nuclear
Quanzhi Yu
Summary: This study obtained the broad neutron spectrum of the Atmospheric Neutron Irradiation Spectrometer (ANIS) through Monte Carlo simulation and provided an analytic expression. By calculating the Single Error Rate (SER) and ratio, the reliability of the ANIS neutron spectrum was evaluated.
APPLIED RADIATION AND ISOTOPES
(2024)
Article
Chemistry, Inorganic & Nuclear
D. Glavic Cindro, M. Korun, T. Petrovic, B. Vodenik, B. Zorko
Summary: In gamma-ray spectrometric measurements, the decision threshold is determined by the observed value of the measurand. However, this dependence restricts its application to measurements with non-expressive indications. To address this issue, a recalculation of the decision thresholds based on the peak widths corresponding to expressive indications is proposed.
APPLIED RADIATION AND ISOTOPES
(2024)