Combination of experimental and simulation methods for determination of effective atomic number by Rayleigh-Compton scattering technique
Le Hoang Minh, Van Thi Thu Trang, Tran Thien Thanh
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY 2025
Abstract:
This paper presents the gamma scattering technique to determine substance' component concentrations. The experimental and simulated R/C ratios of binary oxide samples (Fe2O3and SiO2) were measured. The concentration of each element were interpolated, with a bias relative less than 5% for the elements in the reference samples. The elements' experimental and theoretical Rayleigh-Compton ratio values had a robust relationship in the equation RexpR/C=1.03×RtheoR/C (n = 11; r = 0.99; p-value < 0.01). The Zeff interpolation results and the calculation results from the theoretical formulas have good agreement with an average difference of 5%.
More detail >>
Nguyen Anh TUAN and Chau Van TAO
Nuclear Technology & Radiation Protection: Year 2020, Vol. 35, No. 1, pp. 36-41
Abstract:
An electron beam from the UELR-10-15S2 accelerator (average energy of 9.92 ± 0.48 MeV) was applied to irradiate food and medical items at the Research and Development Center for Radiation Technology, Vietnam Atomic Energy Institute, Vietnam. The materials are under an electron beam window, such as irradiation products, conveyor, magnet and shielding mate- rial for the magnet coil, bombarded by electrons and generated X-ray (bremsstrahlung effect). In this article, X-ray conversion efficiency from polypropylene, aluminum, iron, and lead bombarded by an electron beam from the UELR-10-15S2 accelerator is measured by the film dosimeter and simulated by the MCNP4c2 code, and there is good agreement between the calculation and measurement results. The results show that X-ray conversion efficiency is the highest from lead (4.3 %), so the gamma - neutron reaction (Q-value of –6.74 MeV for 207Pb) has to be studied in food and medical items irradiated by a 10 MeV eelectron beam.
More detail >>
Nguyen Huu Quyet, Le Hong Khiem, Trinh Thi Thu My, Nguyen Thi Bao My, Marina Frontasieva, Inga Zinicovscaia, Nguyen An Son, Tran Thien Thanh, Le Dai Nam, Khuat Thi Hong, Nguyen Ngoc Mai, Trinh Dinh Trung, Duong Van Thang, Nguyen Thi Thuy Hang
Environmental Engineering and Management Journal
Abstract:
Atmospheric deposition of chemical elements in the Hanoi region has been investigated in this study based on moss biomonitoring. Twenty-seven Barbula indica moss samples were collected from the end of 2016 to the beginning of 2017, and the concentrations of 33 chemical elements in the samples were determined by instrumental neutron activation analysis. The results show that Hanoi’s air is highly polluted with Zn, Ba and Ta, and slightly polluted with Al, Cl, Sc, Ti, V, Cr, Mn, Fe, Ni, Co, As, Cd, Sb, La, Ce, Sm, Gd, Tb, Yb, Hf, Th and U. A determination of the possible pollution sources has been made for the analyzed elements; namely: coal and oil combustion are the main sources of V, Ni, Co and As; vehicle exhaust and non-exhaust sources, as well as industrial emissions, are the main sources of Mn, Co, Cd and Ba; construction dust is the source of Ca, Mg and Sb; various industries are the sources of Cr and Ni; the dust from cement kilns and ash from biomass burning is responsible for K and Cl; two-stroke motor vehicles, galvanizing factories and tire wear are the sources of Zn; and Br may be emitted from burning wastes.
Link of this article will be updated.
Benchmarking PHITS for radiation dose assessment from fly ash-blended concrete using MCNP6 and ResRad-Build
Lam Duy Nhat, Le Huu Loi, Le Quang Vuong, Vu Tuan Minh, Ho Van Doanh, Phan Long Ho, Tran Thien Thanh, Hoang Duc Tam
Applied Radiation and Isotopes, vol. 234, p. 112658, Apr. 2026
Abstract
In this study, the PHITS Monte Carlo code is applied for the first time to evaluate indoor radiation exposure associated with fly ash–blended concrete, and its performance is systematically benchmarked against the widely used ResRad-Build program and MCNP6 code. A reference room conforming to RP-112 dimensions (5 m × 4 m × 2.8 m) was modeled, and eight concrete mixtures containing 0–50% fly ash were investigated. The activity concentrations of 226Ra, 232Th, and 40K, along with material composition ratios and densities, were used as input parameters for simulations with PHITS, ResRad-Build, and MCNP6. The annual effective doses calculated using PHITS ranged from 0.378 to 0.489 mSv.y−1. The maximum relative deviations between PHITS and MCNP6 and between PHITS and ResRad-Build were 5.9% and 7.9%, respectively. PHITS exhibited the closest agreement with the reference dose estimate derived from measured activity concentrations, with a maximum relative deviation of 3.6%. These findings clearly demonstrate that PHITS is a highly reliable and effective tool for assessing indoor radiation exposure from building materials.
More details >>
Background subtraction using the SNIP method enhanced by the Levenberg–Marquardt algorithm
Anh Nhi Le, Thanh Tai Chau, Ngoc Ba Vu, Thien Thanh Tran, Le Hao Cong, Van Tao Chau
Nuclear Instruments and Methods in Physics Research Section a Accelerators Spectrometers Detectors and Associated Equipment, 171544 (2026)
Abstract
In this study, a practical refinement of the SNIP method is proposed for background subtraction in HPGe γ-ray spectra. A single filter width determined from the detector specifications is used in Gaussian convolution to obtain preliminary peak parameters, which are then refined using the Levenberg–Marquardt (LM) algorithm to provide more reliable peak widths for SNIP background subtraction. The resulting method, referred to as LMSNIP, is evaluated using the 154Eu spectra measured at 25 cm and 5 cm. The reconstructed backgrounds are directly compared with those obtained using the adaptive SNIP approach, while the resulting net peak areas are compared with Genie2K. For the 25 cm spectrum, LMSNIP and adaptive SNIP provide generally similar background estimates. Under the more demanding 5 cm condition, however, LMSNIP yields a smoother and more stable baseline and generally better agreement with Genie2K for most investigated peaks. Additional validation using the 133Ba spectrum measured at 5 cm further shows that LMSNIP remains effective for a reference spectrum with different low-energy characteristics. These results support the applicability of LMSNIP to background reconstruction and net peak-area determination under the investigated close-geometry conditions.
More detail >>.
