Atomic Electron Density Research Articles

Gamma radiation shielding properties for polymer composites reinforced with bismuth tungstate in different proportions

In this study, inorganic compound (Bi2(WO4)3) was added into the composite to improve the radiation shielding properties of polymer composite. A polymer matrix was prepared by combining unsaturated polyester resin with methyl ethyl ketone peroxide and cobalt octoate (6%), and Bi2(WO4)3 was added to this polymer matrix at different ratios as filling material. In order to investigate the gamma radiation attenuation properties of the obtained polymer composites, mass attenuation coefficients, radiation shielding efficiencies, radiation transmission factors, linear attenuation coefficients, half values layer, tenth values layer, mean free path values, effective atomic numbers and effective electron densities parameters were obtained. Experimental studies were carried out with the help of HPGe detector at 22 different energies emitted from 22Na, 54Mn, 57Co, 60Co, 133Ba, 137Cs, 152Eu and 241Am radioactive sources in the photon energy range of 59.5–1408.0 keV. Each obtained experimental result was compared with the theoretical results. It was observed that the sample encoded with BiWO20 is the best radiation shielding material among all studied composites (except 59.5 keV).

Clinical value of dual-energy CT for predicting occult metastasis in central neck lymph nodes of papillary thyroid carcinoma.

To predict the probability of occult lymph node metastasis (OLNM) in the central cervical by analyzing the dual-energy computed tomography (DECT) parameters derived from papillary thyroid carcinoma (PTC). Data were retrospectively collected from patients with pathologically confirmed PTC who underwent arterial and venous phases of enhanced DECT with concurrent central neck lymph node dissection (CLND). Three clinical features, three shape-related features, and twenty-six DECT-derived parameters were measured. The univariate and multivariate analyses were applied to select the relevant parameters and develop the nomogram. A total 140 cases with negative diagnosis of cervical central lymph node metastases by preoperative evaluation were included, among which 88 patients with metastasis (OLNM +) and 52 patients without metastasis (OLNM -) were finally confirmed by pathology.(1) Anteroposterior/transverse diameter ratio (A/T) derived from the PTC focus had significant difference between the OLNM + and OLNM - groups (p < 0.05). (2) In the arterial phase, iodine concentration (ICarterial), normalized iodine concentration (NICarterial), effective atomic number (Zeff-arterial), electron density (EDarterial), and slope of energy curve (karterial) from PTC focus showed significant difference (all p < 0.05) between the two groups. In the venous phase, only the CT value under the 40keV (HU40keVvenous) had differences (p < 0.05). (3) The nomogram was produced to predict the probability of OLNM, and the AUC, sensitivity, and specificity in the training and test cohort were 0.830, 75.0%, 76.9%, and 0.829, 65.9%, 84.6%, respectively. DECT parameters combined with shape-related feature derived from PTC might be used as predictors of OLNM in the central neck. Preoperative imaging evaluation combining shape-related features and dual-energy CT parameters could serve as a reference to discern occult lymph node metastasis in central neck during the surgically planning of papillary thyroid carcinoma. • Papillary thyroid carcinoma (PTC) patients may have occult lymph node metastasis (OLNM) in the central neck, which is extremely difficult to find by preoperative imaging examination. • Dual-energy CT quantitative evaluation has higher accuracy than conventional CT and can predicting OLNM in the central neck of PTC. • Dual-energy CT quantitative parameters and morphology of PTC can serve as a useful tool in predicting OLNM in the central neck, and as a guide for personalized treatment.

Accurate measurement of effective atomic number and electron density with X-ray attenuation coefficient spectrum

Energy spectra of X-ray attenuation coefficients, μ(E)s, are measured using a system comprising a laboratory X-ray source and a photon-counting-type detector with an accuracy of 3% or less. We propose a method to derive the electron density (ρe) and effective atomic number (Zeff) of an object from measured μ(E) values. The method is based on a simple approximation in which an atomic cross-section of attenuation is expressed by a linear equation of Z4 and experimental calibration using standard materials. The μ(E) values of aqueous ethanol and acetic acid aqueous solutions are measured to get the ρes and Zeffs. The proposed method yielded a ρe value with an accuracy of 1.4% despite the use of standard materials, whereas it yielded a Zeff value with an accuracy of 1.1% for standard materials whose values of Z are similar to that of the sample.

Response investigation of a new polymer gel dosimeter based on ammonium salt through MRI technique

Increasing the use of polymer gel dosimetry (PGD) in radiotherapy requires reducing its toxicity. The toxicity of the PGD components causes risks for the users as well as the environment. The aim of this study is to produce a new PGD called PAGBIT (Polymer, Amps ammonium salt, Gelatin, BIs, Thpc) based on the nontoxic monomer of 2-acrylamido-2-methylpropanesulfonic acid ammonium salt. Furthermore, this monomer is ecofriendly. The PAGBIT PGD was prepared in the laboratory in ambient conditions. PGDs were irradiated using a clinical accelerator with a dose range of 0–10 Gy. The incident photon energy and dose rate were 6-MV and 300 cGy/min, respectively. The irradiated PGDs were imaged using a 1.5T MRI scanner 9 times in a time range of 12–720 h post-irradiation. The maximum obtained sensitivity was 0.115 ± 0.005 Gy−1s−1 at 36 h post-irradiation time. The average sensitivity change as a function of post-irradiation time was 0.0017 Gy−1s−1h−1. However, the average sensitivity change as a function of scanning temperature was 0.0006 Gy−1s−1°C−1. Results showed that the differences of effective atomic number and electron density between PAGBIT and soft tissue were 2.3% and 0.3%, respectively. It was concluded that the PAGBIT is a low toxic, water equivalent PGD with noticeable temporal and temperature stabilities.

Response function and photon interaction of LaBr3:Ce and BGO scintillation detectors by Monte Carlo simulation

This work aims to investigate the response function and photon interaction of the LaBr3:Ce and BGO scintillation detectors using the FLUKA Monte Carlo simulation software. To improve the realism of detectors, the DETGEB card was used to activate the gaussian energy broadening (GEB) function. The GEB parameters of both detectors were obtained by fitting a nonlinear curve to the relation between FWHM and gamma-ray energy. The energy resolution (R), peak-to-Compton ratio (PCR), peak-to-total ratio (PTR), and full-energy peak efficiency (FEPE) of both detectors were investigated by simulation and experiment at different gamma-ray energy obtained from 133Ba, 137Cs, and 60Co sources. The simulated spectra of those radioisotopes were found to agree with the actual spectra. The results found that the R, PCR, and FEPE values of the LaBr3:Ce and BGO detectors tend to decrease as energy increases. Moreover, the total atomic cross-section (σt,a), effective atomic number (Zeff) and effective electron density (Neff) of both crystals was investigated by FLUKA and compared with the XCOM theoretical program covering an energy range of 15 keV to 15 MeV. The simulated results of the σt,a, Zeff, and Neff are in excellent agreement with the theoretical ones. The GEB parameters obtained from this study will improve the simulation performance of LaBr3:Ce and BGO detectors in investigating the gamma-ray response and shielding properties of materials.

Catalytic stannane–fluorine activation triggered by Pd → Sn–F interaction

The chemistry of σ-acceptor (Z-type) ligands has been attracting significant interest for some time, and the geometric and electronic structures featuring Z-type ligands have provided a profound understanding of their distinctive chemical bonds, chemical properties, and reactivities. We herein report that the coordination of Lewis acidic fluorostannane as Z-type ligands enhances their nucleophilicities, opening new opportunities for the development of Pd-catalyzed cross-coupling reaction of fluorostannanes as coupling reagents. Thanks to phosphine chelation, fluorostannane serves as a Lewis acid (Z-type ligand) toward Pd atom and withdraws electron density from the Pd center via the σ*(Sn–F) orbital. Thus, the strong and polar Sn–F bond is efficiently weakened via σ-donation from the Pd center. Accordingly, the F atom in fluorostannane was readily abstracted by even moderate Lewis acidic boranes, leading to the conversion of Z-type stannane to X-stannyl complexes. This key conversion enabled the catalytic arylation of fluorostannane for the first time.

An adaptive decomposition algorithm for quantitative spectral CT imaging

AbstractWith the development of photon counting detectors (PCDs), spectral CT achieves higher performance than in the past, thus has better application prospects. In this paper, an adaptive dual effect decomposition (ADED) algorithm is proposed to perform the quantitative estimation of effective atomic number and electron density. The algorithm is an empirical material identification algorithm that achieves calibration by combining polynomials on the projection data and constraining in the image domain. In addition, we also propose an innovative effective atomic number estimation model with an accurate physical model that adaptively adjusts the parameters according to the x‐ray energy and material type. The performance of the algorithm was verified by experiment and simulation in this paper. Compared to the conventional basis material decomposition algorithm, the proposed ADED algorithm reduces the relative error in the quantification of the effective atomic number from 4.5%–12.0% to 0.3%–4.5%. Overall, the results demonstrate that the proposed algorithm significantly improves the accuracy of quantifying the effective atomic number.

High accuracy interatomic potential model for binary collision approximation and its application into sputtering yield estimation for amorphous carbon

Although binary collision approximation (BCA) and molecular dynamics (MD) are well used for plasma-material interaction simulation, the atomic collision in the energy above 10 eV is often out of scope in general potential model for MD. For BCA, the Ziegler–Biersack–Littmark (ZBL) potential has been often employed for high energy collision. In the present work, as one of modernizations of BCA, more accurate potential model for high energy collision, which is named ReGenerated ZBL (ReGZ) potential, was proposed. The function from of the ReGZ potential was analytically derived from the spherical electron density of an independent atom. To evaluate the potential, sputtering yield and reflection coefficient were compared between the BCA simulations using the ReGZ potential and the ZBL potential. In addition, by also improving the surface binding energy by density functional theory, the sputtering yield using the ReGZ potential becomes consistent with existing results.

Towards the construction of an accurate kinetic energy density functional and its functional derivative through physics-informed neural networks

One of the primary obstacles in the development of orbital–free density functional theory is the lack of an accurate functional for the Kohn–Sham non-interacting kinetic energy, which, in addition to its accuracy, must also render a good approximation for its functional derivative. To address this critical issue, we propose the construction of a kinetic energy density functional throught physical- informed neural network, where the neural network’s loss function is designed to simultaneously reproduce the atom’s shell structures, and also, an analytically calculated functional derivative. As a proof-of-concept, we have tested the accuracy of the kinetic energy potential by optimizing electron densities for atoms from Li to Xe.

Features of Helium-Vacancy Complex Formation at the Zr/Nb Interface.

A first-principles study of the atomic structure and electron density distribution at the Zr/Nb interface under the influence of helium impurities and helium-vacancy complexes was performed using the optimised Vanderbilt pseudopotential method. For the determination of the preferred positions of the helium atom, the vacancy and the helium-vacancy complex at the interface, the formation energy of the Zr-Nb-He system has been calculated. The preferred positions of the helium atoms are in the first two atomic layers of Zr at the interface, where helium-vacancy complexes form. This leads to a noticeable increase in the size of the reduced electron density areas induced by vacancies in the first Zr layers at the interface. The formation of the helium-vacancy complex reduces the size of the reduced electron density areas in the third Zr and Nb layers as well as in the Zr and Nb bulk. Vacancies in the first niobium layer near the interface attract the nearest zirconium atoms and partially replenish the electron density. This may indicate a possible self-healing of this type of defect.

Constructing Mimic-Enzyme Catalyst: Polyoxometalates Regulating Carrier Dynamics of Metal–Organic Frameworks to Promote Photocatalytic Nitrogen Fixation

In nature, nitrogenase can achieve efficient environmental fixation of nitrogen (N2) molecules through π-backbonding mechanism, which inspires us to simulate the N2 fixation process of nitrogenase to overcome the bottleneck in existing artificial synthetic ammonia (NH3), so as to achieve efficient artificial conversion of N2 to NH3 under mild conditions. Herein, we highlight a strategy of constructing a mimic-enzyme catalyst for photocatalytic N2 fixation based on metal–organic frameworks (MOFs) and polyoxometalates (POMs) in which POMs can efficiently regulate carrier dynamics of MOFs to simulate the π-backbonding mechanism of nitrogenase. Oxygen-rich group POMs with strong electronegativity attract electrons from transition-metal atom in MOFs, thus reducing the 3d orbitals’ electron density of transition-metal atom and enhancing unoccupied d-orbitals in favor of adsorbing N2. Simultaneously, the photoexcited electrons in MOFs are efficiently transferred by POMs into the N–N π* antibonding system to activate N2 via π-backbonding mechanism. Taking MIL-88A (C12H6O13Fe) and PMo10V2 (H5PMo10V2O40) as an example, we have obtained a significantly enhanced NH3 production rate of 50.82 μmol g–1 h–1, which is enhanced by 6 times for MIL-88A and 14 times for PMo10V2. Our results make an important contribution to further guidance for artificial N2 fixation under mild conditions.

A quantitative analysis of spectral computed tomography characteristics of osseous metastases.

Spectral detector computed tomography (SDCT) is a recent advancement that enables elemental material decomposition which could improve the detection of osseous metastases in the oncologic patient. Sixteen patients who underwent oncologic staging SDCT as well as WBBS with Technetium-99 m hydroxydiphosphonate (Tc99m HDP) were included in this retrospective study. A total of 50 osseous metastases were identified and confirmed on bone scintigraphy. Quantitative ROI-based measurements of each lesion and a similar region of normal bone were performed, and the acquired spectral data were used for comparison. These parameters included effective atomic number (Zeff ), electron density (%EDW) and calcium suppression (HU). Receiver operating characteristic (ROC) analysis was performed. In comparison to normal bone, osseous metastases showed statistically significantly elevated values in effective atomic number, electron density and calcium suppression. ROC analysis demonstrated outstanding discrimination with area under the curve (AUC) values of 0.934 and 0.915 for effective atomic number and electron density, and excellent discrimination with an AUC value of 0.884 for calcium suppression. Threshold values of effective atomic number (Zeff ) >9.7, electron density >115% EDW and calcium suppression values >0 HU were demonstrated to be able to differentiate an osseous lesion from normal bone with a sensitivity of 82%, 82% and 84% and a specificity of 86%, 92% and 88% respectively. Spectral analysis of osseous metastases demonstrated significantly elevated values in effective atomic number, electron density and calcium suppression as compared to normal bone which would be useful adjunct quantitative parameters in CT imaging to increase diagnostic confidence.

Enhancing Electron Conductivity and Electron Density of Single Atom Based Core-Shell Nanoboxes for High Redox Activity in Lithium Sulfur Batteries.

Herein, an integrated structure of single Fe atom doped core-shell carbon nanoboxes wrapped by self-growing carbon nanotubes (CNTs) is designed. Within the nanoboxes, the single Fe atom doped hollow cores are bonded to the shells via the carbon needles, which act as the highways for the electron transport between cores and shells. Moreover, the single Fe atom doped nanobox shells is further wrapped and connected by self-growing carbon nanotubes. Simultaneously, the needles and carbon nanotubes act as the highways for electron transport, which can improve the overall electron conductivity and electron density within the nanoboxes. Finite element analysis verifies the unique structure including both internal and external connections realize the integration of active sites in nano scale, and results in significant increase in electron transfer and the catalytic performance of Fe-N4 sites in both Li2 Sn lithiation and Li2 S delithiation. The Li-S batteries with the double-shelled single atom catalyst delivered the specific capacity of 702.2 mAh g-1 after 550 cycles at 1.0 C. The regional structure design and evaluation method provide a new strategy for the further development of single atom catalysts for more electrochemical processes.

Radiation attenuation and photon trajectories behaviors of quadruple glass system: 60SiO2-35Pb3O4-(5-x)ZnO-xWO3

Ionizing radiation is becoming increasingly prevalent in various applications on Earth and in space. This study evaluates the radiation shielding performance of five quaternary glass systems with different chemical compositions of 60SiO2-35Pb3O4-(5-x)ZnO-xWO3 (0 ≤ x ≤ 5 mol%) using theoretical software and Monte Carlo simulations. The study calculates various shielding parameters, including attenuation coefficients, mean free path, half value layer, tenth value layer, effective atomic number, electron density, and build-up factors, for the photon energy range of 1 keV to 100 GeV. PZSW3 and PZSW5 show comparable attenuation coefficients at low and high energy levels, which are higher than the other selected samples. Additionally, PZSW5 has a neutron removal cross-section of 0.120 cm−1, slightly less than PZSW4’s 0.122 cm−1 and greater than the other three samples. On average, PZSW5 (60SiO2-35Pb3O4-5WO3) exhibits greater radiation attenuation than other samples and most of the compared 19 samples in terms of shielding parameters. The study also analyzes the trajectories of 105 photons in the system and finds that PZSW5 has the most effective radiation protection capability among the glass composites studied.

Coordination number engineering of Zn single-atom sites for enhanced transfer hydrogenation performance

Metal single-atom catalysts (SACs) have great potential to replace traditional nanoparticle catalysts in practical applications, however, the task-specific construction of SACs containing metal–nitrogen (M−N) moiety with tunable M−N coordination number remains a colossal challenging issue. Herein, we report a facile strategy to modulate the s-band of Zn by constructing N-coordinated Zn SACs (denoted as Zn–N–C–T, T stands for the pyrolysis temperature) with tunable nitrogen coordination number (denoted as Zn–Nx, x = 2, 3, and 4) and Zn loadings (ranging from 0.8 to 6.8% by weight) via a metal–organic framework-mediated pyrolysis method. The catalytic activity of Zn–N–C–T is found to be closely related to the coordination number of Zn single atomic sites for the transfer hydrogenation of nitroarene to arylamine, using hydrazine hydrate as a hydrogen source under environmental benign conditions, among which the under-coordinated Zn–N3 with defect and asymmetric electron distribution in Zn–N–C–1223 exhibits the best catalytic activity, followed by lower-coordinated Zn–N2 with defect in Zn–N–C–1273 and saturated coordination Zn–N4 in Zn–N–C–1123. Experimental results and theoretical analysis uncover that appropriately lowering the coordination number increases the electron density of Zn single atoms and simultaneously introduces H-acceptor sites, which cooperatively contribute to the enhancement of the performance for transfer hydrogenation.

LaMnxCo1‐xO3 (x=0, 0.25) Perovskites: Novel Nano Catalysts for Removal of Thiophene compounds in Fuels by Catalytic and Ultrasound‐assisted Oxidative Desulfurization

AbstractLaMnxCo1‐xO3 (x=0, 0.25) perovskites were developed as novel nanocatalysts for the desulfurization of thiophenes compounds by catalytic oxidative desulfurization (CODS) and ultrasound‐assisted oxidative desulfurization (UAOD). The perovskites were synthesized by the sol‐gel auto‐combustion method and characterized by X‐ray diffraction (XRD), temperature programmed reduction (TPR), Scanning electron microscopy (SEM) and BET surface area. The experiments were designed by the Box‐Behnken method of response surface methodology. The catalytic experiments were designed by response surface methodology (RSM). LaMn0.25Co0.75O3 despite having a lower surface area rather than LaCoO3 exhibited superior activity due to easy reducibility and high surface electron density approved by TPR. Pareto analysis indicated that the DBT concentration had the most effect on the CODS process. Ultrasound waves enhanced the activity of the catalysts via the formation of hot spots as an accelerating and de‐agglomerating agent in the UAOD process, leading the LaMn0.25Co0.75O3 to be reusable at least for 5 cycles. A mechanism for DBT oxidation was proposed by the formation of DBT sulfone. Due to steric hindrance and the electron density of the sulfur atoms in thiophene derivatives, the following order resulted in their desulfurization rate: DBT&gt;4‐MDBT&gt;BT. The study indicated that perovskites could be novel and promising nanocatalysts for the desulfurization of fuels.

Geometric Tuning of Single-Atom FeN4 Sites via Edge-Generation Enhances Multi-Enzymatic Properties.

Single-atom nanozymes (SAzymes) are considered promising alternatives to natural enzymes. The catalytic performance of SAzymes featuring homogeneous, well-defined active structures can be enhanced through elucidating structure-activity relationship and tailoring physicochemical properties. However, manipulating enzymatic properties through structural variation is an underdeveloped approach. Herein, the synthesis of edge-rich Fe single-atom nanozymes (FeNC-edge) via an H2 O2 -mediated edge generation is reported. By controlling the number of edge sites, the peroxidase (POD)- and oxidase (OXD)-like performance is significantly enhanced. The activity enhancement results from the presence of abundant edges, which provide new anchoring sites to mononuclear Fe. Experimental results combined with density functional theory (DFT) calculations reveal that FeN4 moieties in the edge sites display high electron density of Fe atoms and open N atoms. Finally, it is demonstrated that FeNC-edge nanozyme effectively inhibits tumor growth both in vitro and in vivo, suggesting that edge-tailoring is an efficient strategy for developing artificial enzymes as novel catalytic therapeutics.

Determination of Gamma Radiation Shielding Characteristics for Some Iron-Based Metallic Glasses

In this study, the gamma radiation shielding characteristics of metallic glasses having Fe81B13.5Si3.5C2, Fe79B16Si5, Fe78B13Si9 and Fe40Ni38B18Mo4 components and coded as FeBSiC, FeBSi1, FeBSi2 and FeNiBMo were investigated. In order to investigate, the mass attenuation coefficients for metallic glasses in the photon energies range of 0.060 to 2.614 MeV were calculated with the help of WinXCOM program and GEANT4 and FLUKA simulation codes. The linear attenuation coefficient, half and tenth value layers, mean free path, effective atomic number and electron density parameters were calculated with the help of the calculated mass attenuation coefficients. Variations of the calculated gamma radiation shielding parameters with photon energy were discussed. It was observed that mass and linear attenuation coefficients, effective atomic number and electron density parameters decreased with increasing photon energy, while half and tenth value layers and mean free path parameters increased with increasing photon energy. It has been observed that metallic glasses have better gamma shielding capabilities in the low photon energy region, and metallic glass coded as FeNiBMo has better gamma radiation shielding capacity than other studied metallic glasses.

Assessment of X-ray shielding properties of polystyrene incorporated with different nano-sizes of PbO.

PbO (lead oxide) particles with different sizes were incorporated into polystyrene (PS) with various weight fractions (0, 10, 15, 25, 35%). These novel PS/PbO nano-composites were produced by roll mill mixing and compressing molding techniques and then investigated for radiation attenuation of X-rays (N-series/ISO 4037) typically used in radiology. Properties of the PbO particles were studied by X-ray diffraction (XRD). Filler dispersion and elemental composition of the prepared nano-composites were characterized using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS), revealing better filler distribution and fewer agglomerations with smaller PbO particle size. Linear and mass attenuation coefficients (μ and μm), total molecular and atomic cross-sections (σmol and σatm), as well as effective atomic number and electron density (Zeff and Neff), were calculated for the energy range N40 to N200. The influence of PbO weight percentage on the enhancement of the shielding parameters of the nano-composites was expected; however, the effect of PbO particle size was surprising. Linear and mass attenuation coefficients for PS/PbO composites increased gradually with increasing PbO concentrations, and composites with a small size of nanoparticles showed best performance. In addition, increasing PbO concentration raised the effective atomic number Zeff of the composite. Hence, the electron density Neff increased, which provided a higher total interaction cross-section of X-rays with the composites. Maximum radiation shielding was observed for PS/PbO(B). It is concluded that this material might be used in developping low-cost and lightweight X-ray shielding to be used in radiology.

Assessment on gamma radiation shielding properties of molybdenum doped bricks

Gamma radiation permeability experiments were carried out by preparing a new type of brick mixture with Molybdenum (Mo, Z = 42) additives (0 (B0), 5 (B1), 10 (B2), 20 (B3), 30 (B4), 40 (B5), 50 (B6) %wt). The density of the bricks increased to 2.79 g/cm3 with increasing Mo content. The bricks were exposed to gamma rays with 81, 276, 303, 356 and 383 keV photon energies emitted from 133Ba radioactive source and the transmitted intensities were detected using the Canberra Ultra Ge detector. Gamma attenuation characteristics of the bricks were also calculated by mass attenuation coefficients, effective atomic numbers and electron densities using the EpiXS program as a function of gamma-ray energy. And also, the exposure and energy absorption buildup factors of bricks were determined at different mean-free paths and photon energies using EpiXS program. It was observed that as the density of the bricks increased, the radiation shielding properties also increased. The values of the mass attenuation coefficients at 81 keV for B0–B6 bricks were found to vary between 0.229 and 1.08 cm2/g. It was found that Zeff values were 13.3, 16.1, 17.4, 19.09, 22.5, 25.3 and 26.6 for B0, B1, B2, B3, B4, B5 and B6 samples at 81 keV, respectively. As can be seen from these results, B6 brick has the highest Zeff value. And also, the calculated results displayed that the lowest values of exposure buildup factors and energy absorption buildup factors are observed for the B6 brick. The B6 brick containing 50% Mo element has a higher mass attenuation coefficient and effective atomic number values than the other bricks. The values of exposure and energy absorption buildup factors of B6 brick were lower than the values of other investigated samples. The measured and calculated shielding values of the bricks were in close agreement. It has been seen that the shielding results of these new types of bricks, which are low in cost and easy to produce and use, are quite successful.