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The article presents a kinetic model describing the lead vapor oxidation in the vapor bubble volume to produce lead oxide and hydrogen with their subsequent dissolution in the lead melt volume. The model is implemented in the approximation of homogeneous distribution of reagents and oxidation reaction products in the bubble volume. An analytical solution for stationary oxidation conditions is obtained. It is shown that vapor bubbles in the lead melt volume are a sort of chemical "microreactors" producing lead oxide and hydrogen, which subsequently dissolve in the melt volume. However, such hydrogen generation mechanism does not pose any threat for the primary coolant circuit of fast lead cooled reactors in terms of hydrogen accumulation and explosion hazard in view of essentially low intensity of the hydrogen generation source. The article presents the results of water to hydrogen conversion assessments carried out with the use of a homogeneous kinetic model for interaction of water vapor with lead vapor in the vapor bubble volume. The model incorporates mechanisms governing lead evaporation into the bubble volume, oxidation of lead vapor as it interacts with water vapor in the bubble volume, and dissolution of reaction products in the lead melt surrounding the bubble. One more important result of equilibrium thermodynamic computations is connected with a possible change in the composition of iron oxides in the melt after the injection of water from the steam generator leak into the melt. The ingress of water into the lead melt may cause a change in the composition of iron oxides, thereby increasing the fraction of hematite and decreasing the fraction of magnetite. This may entail a change in the composition of the protective oxide film on the structural steel surface to make it more brittle. [ABSTRACT FROM AUTHOR]

Abstract In the present work, a glass system with developed composition consisting of B2O3, ZnO, Na2O and Fe2O3 samples has been investigated. Glass samples were prepared using the melt quenching method and the density of the system was measured using Archimedes’ principle. Spectroscopic analysis using a gamma source and a high-purity germanium detector at four energies of 0.0595, 0.6617, 1.173, and 1.333 MeV emitted from Am-241, Cs-137, and Co-60 were used to determine the attenuation parameters of present glass composites. The sample containing 45 B2O3 + 10 Na2O + 40 ZnO + 5 Fe2O3 (coded BNZF-4) had the highest mass attenuation coefficient (MAC) value at all the energies discussed compared to the other composites. Whoever, the BNZF-1 sample had the lowest value at all ranges of energies. The transmission factors (TF, %) of the manufactured samples were calculated, at 0.0595 MeV (TF, %) values are 32.6429 and 6.4612 for samples BNZF-1 and BNZF-4, respectively. The statistical results demonstrated significantly better to increase the ZnO concentration in the sample, where the percentage of zinc oxide inside the prepared glass samples has the following direction BNZF -4 > BNZF -3 > BNZF -2 > BNZF -1. The significance of this study is that transparent, environmentally harmless glass composites with relatively high density have been prepared that can be used as shielding materials against gamma rays, especially at low energies.

This work demonstrates a new sol-gel approach for synthesizing PbO2-doped zirconia using zircon mineral precursors. The streamlined methodology enables straightforward fabrication of the doped zirconia composites. Comprehensive materials characterization was performed using XRD, SEM, and TEM techniques to analyze the crystal structure, microstructure, and morphology. Quantitative analysis of the XRD data provided insights into the nanoscale crystallite sizes achieved, along with their relationship to lattice imperfections. Furthermore, the gamma-ray shielding capacity for the PbO2-doped zirconia samples was estimated by the Monte Carlo simulation, which proves an increase in the gamma ray shielding properties by raising the Pb concentration. The linear attenuation coefficient increased between 0.467 and 0.499 cm−1 (at 0.662 MeV) by increasing the Pb content between 11 and 21 wt%. By increasing the Pb content to 21 wt%, the synthesized composites' lead equivalent thickness reaches 2.49 cm. The radiation shielding properties for the synthesized composites revealed a remarkable performance against low and intermediate γ-ray photons, with radiation shielding capacity of 37.3 % and 21.4 % at 0.662 MeV and 2.506 MeV, respectively. As a result, the developed composites can be employed as an alternative shielding material in hospitals and radioactive zones.

Experimental investigation and thermodynamic modeling of the phase equilibria in the (PbO)-NiO-ZnO-SiO 2 system has been undertaken to characterize Ni behavior in high-Zn slags. Phase equilibria data at 790–1700 °C were obtained through equilibration of synthetic mixtures in sealed silica ampoules or Pt-Ir / Au foils, rapid quenching, and electron probe X-ray microanalysis. Phase equilibria and liquidus isotherms of the NiO-ZnO-SiO 2 system in the tridymite/cristobalite SiO 2 , monoxide (Ni,Zn)O, zincite (Zn,Ni)O, olivine (Ni,Zn) 2 SiO 4 and willemite (Zn,Ni) 2 SiO 4 phase fields were measured and the extent of the 2-liquid immiscibility gap over cristobalite was determined. Additional solid solutions: larsenite Pb(Zn,Ni)SiO 4 and melilite Pb 2 (Zn,Ni)Si 2 O 7 were measured in the PbO-NiO-ZnO-SiO 2 system. It was found that NiO partially substitute ZnO in larsenite and melilite and may form a complete range of solubility in barysilite Pb 8 (Zn,Ni)Si 6 O 21. New data were used for developing a thermodynamic database to describe the Pb/Cu-containing complex system for characterizing Ni behavior in Zn-containing slags. [ABSTRACT FROM AUTHOR]

Melt quenching method was used to prepare a glass series composed of 5MgO-20PbO-10SiO2-(65-x)B2O3-xBaO, (x = 10, 15, 20 and 25 mol%), with the resulting glasses' capacity for radiation shielding explored through Phy-X software. The mass attenuation coefficients (MAC) were examined in the 0.122–1.485 MeV energy range, with 0.122 MeV the resulting maximum value and a 1.557–1.611 cm2/g variation. At the low energy range, a clear relationship between the MAC and the energy emerged, with 0.054 cm2/g at 0.122 MeV representing the MAC difference between the lowest and highest BaO-content glasses. Conversely, at the high energy range, the influence of BaO on the MAC diminished considerably, whereby the MAC difference between the two glasses was a mere 0.001. We evaluated the prepared glasses' linear attenuation coefficients (LAC), finding a direct relation between the LAC and glass density. At 0.245 MeV, the LAC values were 1.425, 1.486, 1.546, and 1.607 cm−1 at the respective densities of 4.275, 4.438, 4.601, and 4.764 cm−1. According to the LAC results, the glass with the composition of 5MgO-20PbO-40 B2O3-10SiO2-25BaO has the more desirable shielding properties. We observed a decrease in the TF with increasing the amount of BaO in the prepared glasses. This observation implies that BaO has an important role in enhancing the glasses' radiation shielding ability. [ABSTRACT FROM AUTHOR]

The phase equilibria of the ZnO-"FeO 1..5 ", ZnO-"FeO 1.5 "-SiO 2 , PbO–ZnO-"FeO 1.5 " and PbO–ZnO-"FeO 1.5 "-SiO 2 slag systems in equilibrium with air or metallic lead/iron were studied as part of the investigation of the 19-component PbO–ZnO–Cu 2 O–FeO–Fe 2 O 3 –CaO–SiO 2 –Al 2 O 3 –MgO–S-(As, Sn, Sb, Bi, Ag, Au, Ni, Cr, Co as minor elements) slag/matte/metal/speiss/gas system, supporting the operation/development of existing and emerging pyrometallurgical processes. In the experimental part of the study, samples underwent high temperature equilibration followed by quenching, and the direct measurement of the lead, zinc, iron and silicon concentrations in the liquid slag, solid oxide, and metal phases by electron probe microanalysis (EPMA). The a) massicot (PbO), b) spinel ((Zn, Fe)Fe 2 O 4), c) zincite ((Zn,Fe)O 1+x , 2 polymorphs), d) lead ferrite (Pb 2+x Fe 2 O 5+x), e) plumboferrite (Pb 4 Fe 22-x Zn x O 37), f) magnetoplumbite (Pb(Fe 2 O 3 ,PbFeO 2 ,PbZnO 2)Fe 10 O 16), and g) W-ferrite (PbZn 2-x Fe 16+x O 27) primary phase fields of the PbO–ZnO-"FeO 1.5 " system in equilibrium with air were studied between 780 and 1300 °C. The ZnO-"FeO 1.5 ", ZnO-"FeO 1.5 "-SiO 2 and PbO–ZnO-"FeO 1.5 "-SiO 2 systems in equilibrium with air were studied up to 1745 °C, significantly improving the availability of information on the composition range of the high- and low-Fe zincite ((Zn,Fe)O 1+x) phases, and on the liquid slag composition at the boundaries of their primary phase fields. Lastly, the solubilities of iron in larsenite (Pb(Zn,Fe)SiO 4) and melilite (Pb 2 (Zn,Fe)Si 2 O 7) in equilibrium with air or metal were studied between 700 and 800 °C. The newly obtained and existing experimental data were used to develop a self-consistent set of thermodynamic parameters describing all phases in the system using the FactSage computer package. [ABSTRACT FROM AUTHOR]

Periodic nanostructures, including gratings, which have been widely used in the fields of photonics and plasmonics, are generally fabricated through electron beam lithography, photolithography, or laser-induced periodic surface structure (LIPSS) formation. Although photomasks or photoresists are not necessary for the preparation of LIPSSs, a laser is required as a coherent light source. Here, we propose a photoelectrochemical bottom-up approach to obtain semitransparent periodic nanostructures using an incoherent continuous light source. Lead oxide nanoband arrays are formed simply by irradiating linearly polarized light to a potential-controlled indium-tin oxide electrode in the presence of Pb2+ ions. The polarized light causes anisotropic growth of lead oxide parallel to the polarization direction, and interference between incident light and light scattered from the nanostructures gives rise to the periodicity. The pitch of the subwavelength scale can be controlled by the irradiation light wavelength. [ABSTRACT FROM AUTHOR]

An integrated experimental and thermodynamic modeling investigation of the phase equilibria in the PbO–NiO–SiO2 system in air and also in equilibrium with liquid metal has been undertaken to better characterize the chemical reactions taking place in the Ni‐containing Pb processing slags. New experimental phase equilibria data at 720°C–1740°C were obtained for this system using high‐temperature equilibration of synthetic mixtures with predetermined compositions in sealed silica ampoules or in Au/Pt–Ir foils, a rapid quenching technique, and electron probe x‐ray microanalysis of the equilibrated phase compositions. Phase equilibria and liquidus isotherms in the quartz/tridymite/cristobalite (SiO2), olivine (Ni2SiO4), monoxide (NiO), Ni‐barysilite (Pb8NiSi6O21), massicot (PbO), and di‐lead silicate (Pb2SiO4) primary phase fields were revealed and the extent of the high‐SiO2 two‐liquid immiscibility gap in equilibrium with cristobalite was determined. New experimental data were used in the development of a thermodynamic database describing this ternary system. Also, modeling revision of the NiO–SiO2 binary system was conducted, resulting in a smaller miscibility gap in ternary systems that was closer to the experimental results. [ABSTRACT FROM AUTHOR]

In this work, we reported the radiation-shielding properties of PbO-PbF2-B2O3-SiO2 glass systems. Using Phy-X software, we determined the mass and linear attenuation coefficients, and other related parameters to understand the radiation-shielding performance of these glasses. The mass attenuation coefficient (MAC) values for the glasses at 0.284 MeV range from 0.308 to 0.355 cm2/g, while at 1.333 MeV they are all around 0.055 cm2/g. The MAC results demonstrated that the attenuation capability of the glasses decreased when faced against higher energy photons, while they have better attenuation performing against lower energy radiation. Glass with a composition of 14PbO-42PbF2-14B2O3-30SiO2 possesses the highest MAC and LAC, which means that this glass has the greatest advantage over the other samples. We evaluated the percentage decrease in half value layer (HVL) between the glasses with 21 and 42 mol% of PbF2 and 42PbF2. At 0.284 MeV, the percentage decrease is equal to 24.8%, demonstrating a huge advantage in adding more PbF2 at low energies. As the photon energy increases to 1.333 MeV, the percentage decreases to 13.6%. We investigated the relation between the tenth value layer (TVL) of the glasses and their PbF2 to B2O3 ratio, and we found that the ratio varies from 0.6 to 3 cm. This indicated that raising the PbF2 content relative to the concentration of B2O3 leads to a glass with greater space efficiency. The mean free path (MFP) values for the glasses at 0.284 MeV are equal to 0.669, 0.587, 0.538, and 0.503 cm at 21, 28, 35, and 42 PbF2 mol%, respectively, [ABSTRACT FROM AUTHOR]

New glass samples were synthesized from the binary system LiF. PbO with different ratiosby the traditional melt-quenching technique. The corresponding glass-ceramics were formed by heat treating the prepared glasses. Differential Scanning Calorimetry (DSC), X-ray diffraction (XRD), Fourier transform infrared (FT-IR) and Transmission electron microscope (TEM) were employed to study the structure of the samples; while characterization of the glass and glass-ceramics were studied using photoluminescence (PL) spectral analysis, electrical, UV–Visible absorption, optical band gap and hardness measurements. The ability to form glass was increased with increase PbO content (1LiF:≥5PbO). Tetragonal and orthorhombic PbO, orthorhombic and monoclinic Pb 2 O 3 , α-PbF 2 and traces of both Li 4 PbO 4 , PbO 1.37 were crystallized under specific heat-treatment circumstances as identified by XRD analysis. The crystal size decreased with increasing the PbO content; it reaches ∼15 nm in case of 10 Pb. PL revealed concentration quenching in glass with 10 Pb, a red shift and enhancement of bands intensity were observed with decrease λ ex , increase heat-treatment temperature and increase PbO concentration. The UV–Visible absorption elucidated that the cutoff wavelength (λ) was shifted toward lower wavelength (blue shift) by increasing PbO content and the values of optical band gap energies recorded 2.69, 2.66 and 2.72 eV for LiF·5PbO, LiF·8PbO, and LiF·10PbO, respectively. The electrical properties recorded conductivity ∼1.2 × 10−6 S m−1 and dielectric constant ∼ 46.8. These characteristics suggests that, the prepared materials exhibited semiconducting and photoluminescence behavior nominated it to be utilized in solar cell applications. [ABSTRACT FROM AUTHOR]

In this study, we have reported the synthesis of both pure and bismuth‐doped lead oxide nanoparticles using solvothermal method. The synthesized nanomaterials were analyzed to assess their structure, crystallinity, phase, maximum absorption and band gap. The electrical characteristics of the fabricated nanostructures were evaluated using cyclic voltammetry (CV) and electron impedance spectroscopy (EIS). The maximum specific capacitance and energy density, 349.96 F/g and 95.27 Wh/g respectively, were attained at a scan rate of 200 mV/s in pure lead oxide. The synthesized pure lead oxide has displayed remarkable cyclic stability, retaining approximately 83 % of its performance even after undergoing 2000 cycles. The addition of bismuth to the lead oxide appeared to inhibit the electrochemical properties of lead oxide due to bismuth ion adsorption. This effect is directly concerned with the amount of dopant which predicted the increase in bismuth contents potentially suppressed the performance of the lead oxide. Our study provides insights into the possible uses of lead oxides in energy storage and conversion devices by revealing a previously unexplored method for optimizing their electrochemical characteristics. The understanding of oxide‐based materials in materials science and electrochemistry is expected to advance with the use of this novel technology. [ABSTRACT FROM AUTHOR]

A series of polyepoxide resins doped by lead oxide with low concentrations were fabricated in order to study the impacts of low PbO concentrations on the fabricated composites’ physical- and radiation-shielding properties. The epoxide resin was reinforced with the PbO compound with concentrations 0, 5, and 10 wt%. The density measurements affirmed that by elevating the PbO concentration between 0 and 10 wt%, the composites’ density increased from 1.103 to 1.185 g·cm−3. This low-density increase was echoed in the fabricated composites’ radiation-shielding properties, where the Monte Carlo simulation code affirmed a linear attenuation coefficient increase by factors of 230%, 218%, 24%, and 10%, respectively, at 59, 121, 356, and 662 keV. The half-value layer, mean free path, and transmission factor indicated a linear attenuation coefficient enhancement.

The current study describes the plant-mediated synthesis of lead oxide nanoparticles (LO) using a plant extract from Chinese Mahogany (CMPE). The invented nano-hybrid structure (CMPE@LO) has been used for the fast green (FG) dye degradation as well as bio-medical applications. The prepared nanoparticles were characterized using techniques like Fourier transform infrared spectrogram (FTIR), X-ray diffractometer (XRD), field emission scanning electron microscope (FESEM), high-resolution transmission electron microscope (HRTEM), and thermo-gravimetric analysis (TGA). The presence of Pb, O, and C components in the EDX spectrum verified the formation of the desired nanocomposite. The crystalline nature was confirmed by XRD measurements, which showed nanoparticles with a size of 22.56 nm. The FESEM study presents a rod-like, rough, and spongy surface for the removal of contaminants from a water system. The various operating parameters such as the effect of time, concentration of fast green, and photocatalyst amount were also studied and optimized for maximum removal. The kinetic study was investigated using a pseudo-first model having a good value of regression coefficient (R2). The antibacterial properties of the prepared nanoparticle against bacteria including Bacillus subtilis, Staphylococcus aureus, and Escherichia coli were also investigated. The synthesized CMPE@LO nanoparticles show a higher zone of inhibition as compared to inorganic or organic moiety. Hence, these findings present that the (CMPE@LO) nano-hybrid structure can be employed as a photocatalyst for fast green (FG) dye and antimicrobial agent against pathogenic bacteria. [ABSTRACT FROM AUTHOR]

This study examines the high-frequency-dependent characteristics of the PbO/SnO2 double-layer semiconductor (DLS) structures. Recently, researchers have been particularly interested in such structures in terms of their use in electrical and photovoltaic applications. A PbO/SnO2 double layer was successfully coated on a p-type Si substrate (100) wafer with a resistance of 10 Ω cm and a thickness of 280 μm. The Al Schottky (round dot) connections, which have a thickness of 124 nm and a diameter of 1.3 mm, were produced by thermal evaporation. The present study proposes to measure the conductance–voltage (G–V) and capacitance–voltage (C–V) values of the studied Al/PbO/SnO2/p-Si Schottky diode for the frequencies of 500 kHz, 800 kHz, and 1 MHz at a temperature of 300 K, which has been suggested for the first time in literature. Due to the presence of surface states (Nss), PbO/SnO2 double-layer, and series resistance Rs, the C–V and G–V plots show inversion, depletion, and accumulation zones depending on the strong frequency for each frequency tested. Based on the tested frequencies, the reverse-biased C2–V curves are used to compute the fundamental electrical characteristics of the Al/PbO/SnO2/p-Si structures, including the depletion layer (WD), Fermi energy level (EF), diffusion potential (VD), and thickness barrier height (⌀B). We also investigated the capacitance features and the energy density distribution of surface states (Nss) in the PbO/SnO2 double-layer structure by utilizing the measured values of G–V and C–V. The values of ⌀B, VD, and Nss were observed to be 0.54 0.34, and 3.19 10 12 eV–1 cm–2 at 500 kHz, while they were 0.88 0.68, and 1.96 eV–1 cm–2 at 800 kHz and 0.95, 0.75, and 1.47 eV–1 cm–2 at 1 MHz, respectively. It was discovered that the capacitance characteristics of the PbO/SnO2 double-layer structure were substantially dependent on the applied high frequencies. Furthermore, the C–V and G–V measurements revealed that the series resistance and the interface state density of the studied Al/PbO/SnO2/p-Si Schottky diode were critical parameters that significantly affect the electrical parameters offered by the PbO/SnO2 double-layer nanostructure. The results of the study reveal that the manufactured device exhibits outstanding electric characteristics and support the possibility of using DL thin films in electronic devices. [ABSTRACT FROM AUTHOR]

PbO NPs have been prepared by green synthesis. The diffraction patterns of a-PbO-NPs are shown by the XRD pattern, and the ß-PbO-NPs have proven the tetragonal and orthorhombic structure. PbO has an optical energy gap of 4.2 eV. The FT-IR observed bond at 676 cm-1 attributed to the existence of PbO stretch. Nanoparticals with spherical and semi-spherical shapes are formed, as seen in the SEM image. The average particle size was under 100 nm. Fabrication and characterization of a high performance Ag/PbO/PSi/pSi/Ag heterojunction photodetector. The photodetector's responsivity was 0.7 A/W at 850 nm. The maximum detectivity and quantum efficiency spectra 1.009 ×1013 at 850 nm and 3×10² at 200nm which indicates that PbO NPs made using this technique have a good chance of being used to create porous silicon photodetectors with high performance heterojunctions. [ABSTRACT FROM AUTHOR]

The phase equilibria of the PbO–ZnO-"CuO 0.5 "- SiO 2 system were studied as part of the investigation of the 19-component PbO–ZnO–Cu 2 O–FeO–Fe 2 O 3 –CaO–SiO 2 –Al 2 O 3 –MgO–S-(As, Sn, Sb, Bi, Ag, Au, Ni, Cr, Co as minor elements) slag/matte/metal/speiss/gas system in support of the development and optimization of pyrometallurgical processes. In the experimental study, samples were equilibrated at high temperatures, then quenched, and the lead, zinc, copper and silicon concentration in the phases were directly measured by electron probe X-ray microanalysis (EPMA). The cristobalite (SiO 2) primary phase field of the PbO–SiO 2 system was experimentally studied between 1575 and 1717 °C. The massicot (PbO), zincite ((Zn,Cu)O), cuprite (Cu 2 O), copper plumbite (Cu 2 PbO 2) and Pb 2 SiO 4 primary phase fields of the PbO-"CuO 0.5 "-SiO 2 , PbO–ZnO-"CuO 0.5 " and PbO–ZnO–SiO 2 systems were studied between 664 and 1100 °C. The cuprite (Cu 2 O), willemite ((Zn,Cu) 2 SiO 4), larsenite (PbZnSiO 4) and melilite (Pb 2 ZnSi 2 O 4) secondary phase fields of the PbO–ZnO-"CuO 0.5 "-SiO 2 system in equilibrium with metal and tridymite/quartz (SiO 2) or zincite ((Zn,Cu)O) were studied between 745 and 1100 °C. The zincite ((Zn,Cu)O), tenorite ((Cu,Zn)O) and willemite ((Zn,Cu) 2 SiO 4) solid solutions in equilibrium with air or pure O 2 at 1 atm were studied between 900 and 1100 °C. Using the FactSage thermodynamic calculation software, a self-consistent set of parameters based on the Modified Quasichemical Model (MQM) were developed to describe the newly obtained and existing experimental data. [ABSTRACT FROM AUTHOR]

In this study, the lead oxide has been successfully synthesized using oxidizing agents (NH4)2S2O8 and applied to decolorize the Remazole Black B (RBB) solution. Lead oxide was synthesized by the batch method through the mechanism of reduction-oxidation and characterized using SEM-EDX and XRD. Decolorizing RBB solution was performed using a modified Fenton method. This study aims to determine the optimum performance of RBB decolorization from lead oxide. The results showed that the crystal formed contains Pb and O. Pb oxide obtained was α-PBO2 with the orthorhombic crystal system. Based on characterization, the lead oxide obtained has a surface morphology of coral flowers-like. Synthesis utilizing equilibrium composition (1:2) and a drying temperature of 100°C yielded Pb oxide, which has a better potential as a modifier in RBB decolorization with a decolorization percentage of 80.07%. The process was then carried out for advanced synthesis less and excess of molar variations. The ratio of lead oxide: NaOH (1:4) showed optimum performance in decolorizing RBB with a decolorization percentage of 80.07 %.

[Display omitted] • Spray pyrolysis is used for lead-acid battery recycling for the first time. • Low-impurity PbO@C is prepared from the recovered lead acetate solution. • Recovered PbO@C shows better electrochemical performance than commercial PbO. • Computational fluid dynamics (CFD) is used for study of spray pyrolysis mechanisms. • The cell made from PbO@C runs 295 charging/discharging cycles (100%DOD). A one-step spray pyrolysis process is investigated for the first time in the field of spent lead-acid batteries (LABs) recycling. The spent lead paste that derived from spent LAB is desulfurized and then leached to generate the lead acetate (Pb(Ac) 2) solution, which is then sprayed directly into a tube furnace to prepare the lead oxide (PbO) product by pyrolysis. The low-impurity lead oxide product (9 mg/kg Fe and 1 mg/kg Ba) is obtained under the optimized conditions (the temperature of 700 °C, the pumping rate of 50 L/h, and the spray rate of 0.5 mL/min). The major crystalline phases of the synthesized products are identified to be α-PbO and β-PbO. In the spray pyrolysis process, Pb(Ac) 2 droplets are sequentially transformed into various intermediate products: H 2 O(g)@Pb(Ac) 2 solution, Pb(Ac) 2 crystals@PbO, and the final PbO@C product. Owning its carbon skeleton structure, the recovered PbO@C product (carbon content of 0.14%) shows better performance than the commercial ball-milled lead oxide powder in battery tests, with higher initial capacity and better cycling stability. This study could provide a strategy for the short-route recovery of spent LABs. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Synthesis of nanoparticles (NPs) for many different uses requires the development of environmentally friendly synthesis protocols. In this article, we present a simple and environmentally friendly method to synthesize lead oxide (PbO) NPs from the plant material of the Mangifera indica. Analytical techniques such as spectroscopy, X-ray diffraction, and microscopy were used to characterize the synthesized PbO NPs, and their photo-electrocatalytic and antifungal properties were also evaluated. H2O2 was used to investigate the efficacy of removing methylene blue dye. At a range of pH values, H2O2 was used to study the role of hydroxyl radicals in the breakdown of methylene blue dye. Methylene blue dyes are more easily eliminated due to increased generation of the *OH radical during removal. Dye degradation was also significantly affected by the aqueous medium’s pH. Additionally, the electrocatalytic properties of the PbO NPs adapted electrode were studied in CH3COONa aqueous solution using cyclic voltammetry. Excellent electrocatalytic properties of the PbO NPs are shown by the unity of the anodic and cathodic peaks of the modified electrode in comparison to the stranded electrode. Aspergillus flavus, Aspergillus niger, and Candida glabrata were some fungi tested with the PbO NPs. Against A. flavus (40%) and A. niger (50%), and C. glabrata (75%), the PbO NPs display an excellent inhibition zone. Finally, PbO NPs were used in antioxidant studies with the powerful antioxidant 2, 2 diphenyl-1-picrylhydrazyl (DPPH). This study presents a simple and environmentally friendly method for synthesizing PbO NPs with multiple uses, including photo-electrocatalytic and antimicrobial activity.

In the paper, results of thermogravimetric study on reaction between lead oxide and lead sulphide, both loose and agglomerated samples. The research results showed that the reaction of lead sulphide with lead oxide is possible at temperatures exceeding 850 oC. Comparing the influence of the reaction temperature on the course of the TG curve and the percentage weight loss of the samples, it was found that the percentage weight loss of the samples increased with the increase of the temperature. This effect was observed both for samples introduced in loose form, as well as for the agglomerated one.

[Display omitted] • Novel nanoparticles, 18C6-FeMOF@Bi 2 O 3 @TiO 2 NPs, were synthesised using titanium dioxide, lead oxide, and iron crown ether. • Characterisation techniques included UV–visible spectroscopy, FTIR, TEM, EDX, XRD, and mapping. • 18C6-FeMOF@Bi 2 O 3 @TiO 2 NPs effectively catalysed the synthesis of 2-phenyl-1H-benzo[d]imidazole with high yield in a short time. • 18C6-FeMOF@Pb 2 O 3 @TiO 2 NPs demonstrated excellent recyclability, maintaining effectiveness over six cycles. • The synthesised compounds exhibited good to moderate antibacterial activity against gram-positive and gram-negative bacteria, compared to the standard drug Ofloxacin , as measured by the zone of inhibition. This study explores the synthesis and application of a novel composite material, 18C6-FeMOF@Pb 2 O 3 @TiO 2 NPs, leveraging their unique physicochemical properties for catalysis and antibacterial activity. The successful production of these nanoparticles was confirmed through FT-IR, SEM, and XRD characterisation techniques. The 18C6-FeMOF@Pb 2 O 3 @TiO 2 NPs demonstrated remarkable efficiency in the one-step synthesis of 2-phenyl-1H-benzo[d]imidazole, achieving high yields under mild conditions and excellent recyclability over six cycles. Additionally, the in vitro antibacterial activity of five newly synthesised substituted 2-phenyl-1H-benzo[d]imidazole derivatives was evaluated against GM + VE and GM − VE bacteria, with results indicating satisfactory to excellent effectiveness compared to the standard antibiotic Ofloxacin. This research highlights the potential of 18C6-FeMOF@Pb 2 O 3 @TiO 2 NPs in both catalytic and therapeutic applications. [ABSTRACT FROM AUTHOR]

• Twelve HSC mixes synthesized with varying PbO and GD percentages, plus a hybrid 5 % PbO+7% GD. • Advanced analysis (XRF, XRD, TEM, EDX) and simulations evaluated microstructure, composition, and radiation shielding. • PbO delayed setting and improved workability of concrete, while GD accelerated setting but reduced workability. • 2% PbO increased compressive strength, while 5% PbO reduced it by 8.57%. The hybrid mix improved radiation shielding. • GD replacement at 7% increased compressive strength by 19.1%, highlighting its beneficial pozzolanic activity. This paper evaluates the influence of bulk lead oxide (PbO) and granodiorite (GD) powders, individually and in combination at optimal replacement ratios, on the setting time, workability, compressive strength, and radiation attenuation properties of high-strength concrete (HSC). Twelve HSC mixes were prepared: a control mix, five mixes containing varying percentages of PbO, five mixes containing varying percentages of GD, and one hybrid mix combining 5 % PbO and 7 % GD. The optimal replacement ratio 7 % with GD powder increased the compressive strength of the concrete by 19.1 %. A comprehensive microstructural and compositional analysis of XBL/G-concrete was conducted employing X-ray Fluorescence (XRF), X-ray Diffraction analysis (XRD), Transmission Electron Microscopy (TEM) and Energy Dispersive X-ray (EDX) techniques. Radiation shielding effectiveness was evaluated using Phy-X software and Monte Carlo-5 simulations (MCS), focusing on γ-rays and fast neutrons. 2 % replacement of PbO enhanced the compressive strength of the concrete. However, increasing the PbO content to 5 % resulted in an 8.57 % reduction in strength compared to the control mix. The hybrid concrete mix of 5 % PbO and 7 % GD demonstrated superior radiation shielding capabilities in terms of linear/mass attenuation, with a 3.12 % increase in compressive strength relative to the control sample. The combined concrete sample of 5 % PbO and 7 % GD were higher than the samples mixed with GD and lower than the samples mixed with PbO of concentrations 3, 4, and 5 % in terms of the linear/mass attenuation. The linear attenuation's order of the XBL/G-concrete samples was: 1BG < 3BG < 5BG < 7BG < 9BG < 1BL < 2BL < 5BLG7 < 3BL < 4BL < 5BL. Also, the mixed concretes of 5 % PbO and 7 % GD demonstrated a superior from fast neutron shielding capabilities. The tested XBL/G-concrete samples provide adequate protection against γ-rays and fast neutrons for nuclear and medical facilities shield radiation. [ABSTRACT FROM AUTHOR]

Lead oxide (PbO) bulk and nanoparticles of two different sizes (A = 78 nm and B = 54 nm) are incorporated separately into the polystyrene matrix at various concentrations (0, 10, 15, 25, and 35 %) using roll mill mixing and compressing molding techniques. The X-ray narrow-spectrum series (N-series / ISO 4037-1) is then used to investigate the radiation attenuation capability of the novel polymer composite PS/PbO, as well as the effect of varying PbO particle sizes on shielding performance. The filler dispersion and chemical elemental analysis of the synthesized composite are investigated using scanning electron microscopy and energy-dispersive X-ray spectroscopy. To determine the mass attenuation coefficients μm, samples with various thicknesses of the synthesized composite are examined using a range of X-ray energies, and the experimental data are compared to theoretical values from NIST databases (XCOM and FFAST). The results indicate that either increasing the filler weight percentage or, decreasing the filler particle size, enhanced the attenuation parameters throughout all energies. The composite containing the smallest nanosize of PbO exhibited the maximum radiation shielding efficacy among all combinations and therefore, might be used to develop low-cost and lightweight X-ray shields.

Traditional pyrometallurgical recovery of spent lead-acid batteries (LABs) requires a temperature higher than 1000 °C, with accompanying hard-to-collect wastes such as lead dust and sulfur oxides. Against this background, sodium carbonate (Na2CO3) was proposed as a low-cost, safe, and non-toxic reagent for recycling the high-risk environmental elements lead (Pb) and sulfur (S), in spent LAB lead paste, enabling the one-step conservation of multi-component Pb species, including lead sulfate (PbSO4), metallic lead (Pb), and lead dioxide (PbO2), to lead oxide (PbO) and sodium sulfate (Na2SO4). The possible reaction pathways of Pb and S species in vacuum roasting was confirmed by Gibbs free energy reaction with an estimated average activation energy of 272.5 kJ/mol. The insoluble PbO in the reaction product (PbO/Na2SO4/Na2CO3) can be recycled by vacuum filtration, while Na2CO3 and Na2SO4 were separated using a carbonation method. Life cycle assessment revealed that for recycling 1.0 t of spent LABs, the vacuum roasting can reduce the carbon footprint −2.1 × 103 kg CO2 eq, promoting global decarbonization. The designed route is highlighted with waste-free production and is outlined by the twelve principles of green chemistry, showing its great engineering application potential for spent LAB recycling.

Thin films of lead sulfide (PbS) are being extensively used for the fabrication of optoelectronic devices for commercial and military applications. In the present work, PbS films were fabricated onto a soda lime glass substrate by using an electron beam (e-beam) evaporation technique at a substrate temperature of 300 °C. Samples were annealed in an open atmosphere at a temperature range of 200–450 °C for 2 h. The deposited films were characterized for structural, optical, and electrical properties. Structural properties of PbS have been studied by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS), and Rutherford backscattering spectrometry (RBS). The results of XRD showed that the PbS thin film was crystalline in nature at room temperature with cubic crystal structure (galena) and preferential (111) and orientation (022). The morphology of the thin films was studied by FESEM, which also showed uniform and continuous deposition without any peel-off and patches. EDS analysis was performed to confirm the presence of lead and sulfur in as-deposited and annealed films. The thickness of the PbS film was found to be 172 nm, which is slightly greater than the intended thickness of 150 nm, determined by RBS. Ultraviolet-Visible-Near-Infrared (UV-Vis-NIR) spectroscopy revealed the maximum transmittance of ~25% for as-deposited films, with an increase of 74% in annealed films. The band gap of PbS was found in the range of 2.12–2.78 eV for as-deposited and annealed films. Hall measurement confirmed the carriers are p-type in nature. Carrier concentration, mobility of the carriers, conductivity, and sheet resistance are directly determined by Hall-effect measurement. The as-deposited sample showed a conductivity of 5.45 × 10−4 S/m, which gradually reduced to 1.21 × 10−5 S/m due to the composite nature of films (lead sulfide along with lead oxide). Furthermore, the present work also reflects the control of properties by controlling the amount of PbO present in the PbS films which are suitable for various applications (such as IR sensors). [ABSTRACT FROM AUTHOR]

The harmless disposal of lead paste in the spent lead-acid batteries (LABs) remains an enormous challenge in traditional pyrometallurgical recycling. Here, we introduced a hydrometallurgical method for the recycling of the spent LABs' waste to obtain the β -PbO as a novel zinc ion batteries (ZIBs) active material. The obtained β -PbO exhibits ultra-flat charge/discharge voltage platforms (0.21 mV/(mAh g−1)) and stable specific capacity. During the charge/discharge, the β -PbO spontaneously triggers the formation of (ZnSO 4)[Zn(OH) 2 ] 3 ·5H 2 O (ZHS) micro-sheets as a surface passivation layer. Moreover, the ex-situ X-ray spectra reveal that the reversible phase transformation occurs between PbSO 4 and Pb with the assistance of ZHS by adjusting the PH value on the electrode-electrolyte interface. The synergistic two-phase-reaction mechanism generates ultra-flat voltage platforms upon the charge/discharge. This "energy-saving and environment-friendly" recycling route eliminates the major source of emission of pollution particulates/gases compared to the traditional pyrometallurgical recycling, while at the same time replacing energy-consuming and environmentally detrimental processes of synthesis of current ZIBs cathodes. [ABSTRACT FROM AUTHOR]

Background. The creation of effective compositions of glasses and special materials based on local raw materials is topical. A comprehensive study of the relevant local raw materials is needed. Purpose. To study the composition, physical and chemical properties of recycled fiberglass and the possibility of obtaining transparent glass. Methodology. Modern physical-chemical and traditional methods of glass technology are used. Originality. It has been experimentally proven that the PbO-SiO2 system consists of 70%PbO+30%SiO2 and 80%PbO+20%SiO2. The possibility of obtaining glass on the basis of the obtained mixture of optimal composition is shown; Findings. An alternative composition of 80% PbO + 20% SiO2 proved to be suitable for lowtemperature firing to obtain transparent glass, it was obtained with a high refractive index. [ABSTRACT FROM AUTHOR]

The search for shielding materials against ionizing radiation is very important due to the harmful effect that these radiations cause on human health and the environment. In this work, new ceramic composites of ErBa 2 Cu 3 O x /lead oxide (ErBaCuO/PbO) instead of pure lead are proposed and prepared to serve as promising alternative materials for gamma radiation protection. X-ray diffraction was used to examine the structural properties of the prepared ceramic composites. The analysis showed that all composites have an orthorhombic structure with Pmmm symmetry. The addition of PbO induced distortion of the crystal structure of the ErBCO system. The structural parameters including lattice constants and unit cell volume showed a great variability with the addition of PbO. The physical properties including the density and porosity of the prepared ceramic composites were also determined. It was found that the density values increased from 4510 kg/m3 for 0 wt% to 4640, 4750, 4800 kg/m3 for 2, 5, and 10 wt%, respectively, while the porosity reduced with increasing the PbO content. The Monte Carlo simulation was used to estimate the linear attenuation coefficients of the as-prepared ceramics at different energies of gamma-ray photons ranging from 0.059 to 1.408 MeV. Other shielding parameters were computed, including half-value thickness, transmission factor, and radiation protection efficiency. The results showed an improvement in radiation protection efficiency and a decrease in the transmission factor values with increasing the concentration of PbO. For example, the half-value thickness reduced from 1.949 to 1.832 cm while the radiation protection efficiency increased from 29.93 to 31.51%, at gamma-ray energy of 0.662 MeV, once the concentration of PbO was increased from 0 to 10 wt %, respectively. [ABSTRACT FROM AUTHOR]

In order to improve the electrical efficiency of lead-acid batteries under partial state of charge, three additives for the negative active mass were synthesized by high-energy ball milling: (1) exfoliated graphite doped with nitrogen groups (GN) from urea and novel (2) ZnO/GN and (3) PbO/GN. The main variables of grinding medium, ball sizes and time were studied. All additives were characterized on Raman, X-ray diffraction (XRD) and scanning electron microscopy and pure, uniform composites of particle size <3 µm were demonstrably obtained. The optimized samples proceeded to electrochemical tests. Particularly, selected PbO/GN4-5 provided a 41% reduction in the current density for the H2 evolution reaction at the working potential on linear sweep voltammetry tests. The produced additives indicated high charge efficiency on the formation process of a 2 V, 36 Ah lead-acid cell. Cycle life performances of cells containing 0.50% (vs. LO) of selected GN4, PbO/GN4-5 and ZnO/GN4-5 surpassed that of commercial graphite, in 75, 328 and 752%, respectively. As a result, the produced additives represent a progress in enhancing commercial additives. The effects of these additives were further investigated after the teardown of the cells. The negative plate was pointed out to be the limiting factor and there is evidence that the additives provided a more uniform distribution and reduced the size of the PbSO4 crystals. [ABSTRACT FROM AUTHOR]

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Lead oxide (PbO) photoconductors are proposed as X-ray-to-charge transducers for the next generation of direct conversion digital X-ray detectors. Optimized PbO-based detectors have potential for utilization in high-energy and dynamic applications of medical X-ray imaging. Two polymorphs of PbO have been considered so far for imaging applications: polycrystalline lead oxide (poly-PbO) and amorphous lead oxide (a-PbO). Here, we provide the comparative analysis of two PbO-based single-pixel X-ray detector prototypes: one prototype employs only a layer of a-PbO as the photoconductor while the other has a combination of a-PbO and poly-PbO, forming a photoconductive bilayer structure of the same overall thickness as in the first prototype. We characterize the performance of these prototypes in terms of electron–hole creation energy (W±) and signal lag—major properties that define a material's suitability for low-dose real-time imaging. The results demonstrate that both X-ray photoconductive structures have an adequate temporal response suitable for real-time X-ray imaging, combined with high intrinsic sensitivity. These results are discussed in the context of structural and morphological properties of PbO to better understand the preparation–fabrication–property relationships of this material. [ABSTRACT FROM AUTHOR]

A validated method was described for the resolution of ternary mixture of copper β-resorcylate (CuR2), lead β-resorcylate (PbR2), and lead oxide in double base solid propellants (DB propellant) without prior separation steps in accordance with military guidelines. Two sets of determination conditions were developed. The first set was based on reaction of Cu (II) and Pb (II) with 4-(2-Pyridylazo) resorcinol reagent in alkaline media and using the mean centering (MC) of ratio spectra method for simultaneous determination of Cu (II) and Pb (II) by measuring the peak intensity at 485 and 555 nm in MC of ratio spectra profiles, respectively. In the second set, with hydrolysis of CuR2 and PbR2 in acetic acid medium, the released resorcylic acid was determined via complex formation of resorcylic acid with Fe (III) at 526 nm. The amounts of CuR2 and total lead can be determined by MC of ratio spectra method. So, according to the data obtained for the resorcylic acid and for the CuR2 plus total lead, the amounts of PbR2 and PbO were determined by applying stoichiometric equations. The calibration curves were linear over the concentration ranges of 0.1–0.9, 0.5–6, 10–130 μg mL−1, for Cu (II), Pb (II), and resorcylic acid, respectively. The method offers reliable approach for the determination of these compounds in DB propellants with acceptable recoveries from 99 to 105%, and RSD less than 3.0%. The method statistically compared based on t- and F-tests with obtained results by the ICP-AES. So, the method can be suggested as a routine method in military quality control laboratories. [ABSTRACT FROM AUTHOR]

The paper presents tests of lead oxidation in a Barton reactor with a capacity of 1200 kg PbO/h, divided into two series. The first series was carried out in conditions of high humidity of the air supplied to the reactor (59–61%), and the second series in conditions of low humidity (19–21%). The study used lead of various purity levels, the main impurities of which were bismuth and silver. The obtained results show that the use of air with a humidity of about 60% in the process allows us to obtain high-quality PbO and has a positive effect on processing parameters such as the amount of lead processed and the efficiency of the process. The mentioned processing parameters significantly influence the production cost of lead oxide. The effect of lead impurities on the process of lead oxidation and the quality of the obtained product was noticed. This dependence is especially visible in the case of the process efficiency, the amount of lead processed per time unit and the amount of formed scrap. The increase in the content of impurities adversely affects each of the parameters mentioned. Optimal parameters of lead oxide regarding the expected acid absorption at the level above 16 g H2SO4/100 g PbO and the degree of oxidation at the level of 75% were obtained for the air humidity of about 60% with the content of pollutants below 100 ppm. The paper presents data on the process parameters and the relationships between them, unpublished in the literature. [ABSTRACT FROM AUTHOR]

The current study aims to explain recent developments in the synthesis of Pb(II)-azido metal-organic coordination polymers. Coordination polymers are defined as hybrid materials encompassing metal-ion-based, organic linkers, vertices, and ligands, serving to link the vertices to 1D, 2D, or 3D periodic configurations. The coordination polymers have many applications and potential properties in many research fields, primarily dependent on particular host–guest interactions. Metal coordination polymers (CPs) and complexes have fascinating structural topologies. Therefore, they have found numerous applications in different areas over the past two decades. Azido-bridged complexes are inorganic coordination ligands with higher fascination that have been the subject of intense research because of their coordination adaptability and magnetic diversity. Several sonochemical methods have been developed to synthesize nanostructures. Researchers have recently been interested in using ultrasound in organic chemistry synthetics, since ultrasonic waves in liquids accelerate chemical reactions in heterogeneous and homogeneous systems. The sonochemical synthesis of lead–azide coordination compounds resulted from very fantastic morphologies, and some of these compounds are used as precursors for preparing nano lead oxide. The ultrasonic sonochemistry approach has been extensively applied in different research fields, such as medical imaging, biological cell disruption, thermoplastic welding, food processing, and waste treatment. CPs serve as appropriate precursors for preparing favorable materials at the nanoscale. Using these polymers as precursors is beneficial for preparing inorganic nanomaterials such as metal oxides. [ABSTRACT FROM AUTHOR]

The concrete is considered as an important radiation shielding material employed widely in nuclear reactors, particle accelerators, laboratory hot cells and other different radiation sources. The present research is dedicated to the shielding properties study of the ordinary concrete reinforced with different weight fractions of lead oxide micro/nano particles. Lead oxide particles were fabricated by chemical synthesis method and their properties including the average size, morphological structure, functional groups and thermal properties were characterized by XRD, FESEM-EDS, FTIR and TGA analysis. The gamma ray mass attenuation coefficient of concrete composites has been calculated and measured by means of the Monte Carlo simulation and experimental methods. The simulation process was based on the use of MCNP Monte Carlo code where the mass attenuation coefficient (μ/ρ) has been calculated as a function of different particle sizes and filler weight fractions. The simulation results showed that the employment of the lead oxide filler particles enhances the mass attenuation coefficient of the ordinary concrete, drastically. On the other hand, there are approximately no differences between micro and nano sized particles. The mass attenuation coefficient was increased by increasing the weight fraction of nanoparticles. However, a semi-saturation effect was observed at concentrations more than 10 wt%. The experimental process was based on the fabrication of concrete slabs filled by different weight fractions of nano lead oxide particles. The mass attenuation coefficients of these slabs were determined at different gamma ray energies using 22Na, 137Cs and 60Co sources and NaI (Tl) scintillation detector. The experimental results showed that the HVL parameter of the ordinary concrete reinforced with 5 wt% of nano PbO particles was reduced by 64% at 511 keV and 48% at 1332 keV. Reasonable agreement was obtained between simulation and experimental results and showed that the employment of nano PbO particles is more efficient at low gamma energies up to 1Mev. The proposed concrete is less toxic and could be prepared in block form instead of toxic lead blocks.

• A series of glass samples fabricated with the (60-x)B2O3-20PbO-20BaO-xZnO glass composition formula (where x has been increased from 0, 5, 10, 15, to 20 mol.%) • The melt-quenching-annealing process was employed in the synthesis of the glass system. • The fabricated sample density was enhanced by 17.6 %, enriching the ZnO concentration to 20 mol%. • The linear attenuation coefficient enhanced by 20.20 %, 16.98 %, and 17.59 % at gamma-ray energy of 0.059 MeV, 0.662 MeV, and 2.506 MeV, respectively, with raising the ZnO concentration from 0 to 20 mol.%. In the present work, a newly produced PbO-BaO-B 2 O 3 glass system's mechanical, physical, and radiation absorption capabilities were studied to determine the effectivity of B 2 O 3 substitution by ZnO. The melt-quench process produced the glasses utilized in the present investigation. The melting point used was 1000 °C, and the temperature at which they were annealed was 400 °C. The experimental measurement of the density for manufactured glass samples was conducted using Archimedes' theory. It was observed that all density values of the fabricated glasses were raised when the concentration of ZnO was increased from 0 to 20 mol.%. Based on the model proposed by Makishima and Mackenzie from Young, bulk, shear, and longitudinal moduli, it was observed that there was a decrease as the concentration of ZnO was increased in the manufactured glasses. Microhardness was found to be reduced from 4.692 GPa to 4.218 GPa, while the Poisson ratio was found to be decreased from 0.234 to 0.229 when the percentage of ZnO was raised from 0 to 20 mol.%. In contrast, the assessment of radiation shielding qualities through the utilization of Monte Carlo software simulation demonstrates an augmentation in the radiation absorption capability of the manufactured glass samples due to the exchange between B 2 O 3 and ZnO compounds. We used the MCNP5 code to study the radiation shielding properties in a wide energy range of 0.03–2.605 MeV. The linear attenuation coefficient LAC of the produced glass samples increased from 0.315 cm−1 to 0.369 cm−1 when the ZnO concentrations were enriched from 0 to 20 mol.%, respectively. [ABSTRACT FROM AUTHOR]

In the paper, results of thermogravimetric study on reaction between lead oxide and lead sulphide, both loose and agglomerated samples. The research results showed that the reaction of lead sulphide with lead oxide is possible at temperatures exceeding 850 oC. Comparing the influence of the reaction temperature on the course of the TG curve and the percentage weight loss of the samples, it was found that the percentage weight loss of the samples increased with the increase of the temperature. This effect was observed both for samples introduced in loose form, as well as for the agglomerated one. [ABSTRACT FROM AUTHOR]

The present work aims to fabricate new inexpensive epoxy-based composites with a concentration described by the formula (90 − x)epoxy + 10Sb2O3 + xPbO, where x = 5, 10, 15, and 20 wt%. The impacts of the substitution of epoxy by PbO on the composite density and radiation shielding properties of the fabricated composites were studied. The density of the fabricated composites varied between 1.30 and 1.49 g·cm−3, enriching the PbO concentration. Utilizing the narrow beam transmission method, the linear attenuation coefficient (LAC) of the fabricated composites was measured using the NaI (Tl) detector as well as radioactive sources Am-241 and Cs-137. The LAC increased by 84% and 18% at gamma-ray energy of 0.059 and 0.662 MeV, when the PbO concentration raised between 5 and 20 wt%, respectively. Then the transmission rate and half-value layer of the fabricated composites were reduced by raising the PbO concentration. Therefore, the fabricated composite has good shielding properties in the low gamma-ray energy interval to be suitable for medical applications and low radioactive waste container constructions.

In this paper, the crystalline phase change of the oxide lead (PbO) particles during thermal annealing was studied; the process was carried out from 150 °C to 750 °C and monitored by thermal and spectroscopic techniques. The synthesis was carried out using chemical precipitation under atmospheric conditions. Scanning electron microscopy (SEM) micrograph of PbO particles revealed platelet-like morphology. The chemical stoichiometry was obtained by energy-dispersive X-ray spectroscopy, an increased in oxygen concentration was found as annealed temperature increased. An increase in thermal diffusivity was recorded up to 19.36 × 10–4 cm2·s−1 in a range 450 °C to 650 °C associated to transformation of the crystalline phase tetragonal–PbO to orthorhombic–PbO. The vibration bands of oxide-metallic bonds were revealed by FTIR spectroscopy. The high crystalline quality of PbO was demonstrated by X-ray diffraction. For PbO tetragonal structures the mean diameter of nanocrystals was 42 nm and for orthorhombic was 53 nm, with bandgap of ~ 3.15 and ~ 2.55 eV, respectively. [ABSTRACT FROM AUTHOR]