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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.

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.

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 %.

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.

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.

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.

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.

Reduction melting methods to remove Pb from lead silicate glasses such as cathode ray tube funnel glass have been extensively studied. In this paper, reduction melting of a model lead glass was conducted using printed circuit board as reductant. Model lead silicate glass, viscosity reducing agent (Na2CO3), and printed circuit board were mixed and melted at 1473 K. Metal phase mainly composed of Pb was formed and settled in the melting glass residue. With increasing printed circuit board addition, the amount of metal phase increased and the concentrations of PbO remained in the glass residue decreased, indicating that addition of printed circuit board is effective to remove Pb from the Pb glass. By EDS analysis, it was confirmed that Cu, Ni and Sn are contained in the metal phase, indicating that metals in printed circuit board are recovered with Pb.

The purpose of this study was to select and propose an applicable method for extracting lead from sphalerite concentrate direct leaching residue. A large number of experiments were conducted to extract lead from sphalerite concentrate direct leaching residue by hydrochloric acid and sodium chloride solution as leachates. The main optimum parameters were determined, such as a liquid-solid ratio of 17.5-1, a reaction temperature of 85°C, an initial hydrochloric acid concentration of 1.3 mol/L, an initial sodium chloride concentration of 300 g/L, and a reaction time of 60 min. Ninety-five percent of the zinc, 96.0% of the iron, and 93.7% of the lead were extracted into leachate at the optimum conditions. The lead in the leachate was in the form of [PbCl4]2-. After the leachate was purified to remove impurities, it was converted into lead oxalate by sodium oxalate as a precipitant. Finally, lead oxalate was decomposed to obtain lead oxide powders via a high-temperature calcination process.

As part of the presented work, tests were carried out to check the possibility of replacing of conventional reducers used in the lead pyrometallurgical processes by cheaper, but equally effective substitutes. For research of lead oxide reduction, the following fine-grained carbonaceous materials were used, ie anthracite dust and coal flotation concentrate, as well as traditional used coke breeze for comparison. The obtained test results indicate a similar ability to reduce the lead oxide of all studied carbonaceous materials.

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.

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.

The paper presents the results of a study of relaxation of the dielectric permittivities in constant electric fields upon switching the polarization of thin films of lead zirconate-titanate, crystallized at different annealing temperatures. It is shown that the relaxation processes are characterized by at least three relaxation times which depend on the crystallization temperature. It is shown that the relaxation processes depend on the localization of lead oxide in the bulk of the film.

An experimental and theoretical study of the formation processes of "impurity" phase inclusions in ferroelectric oxides is carried out via example of polycrystalline lead zirconate-titanate (PZT) films. A feature of these compositions is relatively high volatility of lead oxides, which can lead to deficiency of these components in the composition of the ferroelectric film formed during high-temperature crystallization. To avoid lead losses, some excess is added to the solution in the process of synthesis. Experimental samples of PZT films are obtained using sol-gel method with different contents of lead oxide, the crystallization of the ferroelectric phase of the films is carried out in air at 600 °C. In the films, the inclusions of lead oxide impurity phase are found, and the size distribution of these inclusions are obtained. Model concepts are presented and a system of equations is proposed describing the dispersed inclusions formation kinetics of new phases of different stoichiometric composition at the interfaces in polycrystalline films of multicomponent ferroelectric oxides due to bulk diffusion and grain-boundary segregation. Comparison of the experimental data with the theoretical model gives qualitative agreement. The approach generality makes it possible to extend the model to other systems of multicomponent ferroelectric polycrystalline materials.

The photoconductor layer is an important component of direct conversion flat panel X-ray imagers (FPXI); thus, it should be carefully selected to meet the requirements for the X-ray imaging detector, and its properties should be clearly understood to develop the most optimal detector design. Currently, amorphous selenium (a-Se) is the only photoconductor utilized in commercial direct conversion FPXIs for low-energy mammographic imaging, but it is not practically feasible for higher-energy diagnostic imaging. Amorphous lead oxide (a-PbO) photoconductor is considered as a replacement to a-Se in radiography, fluoroscopy, and tomosynthesis applications. In this work, we investigated the X-ray sensitivity of a-PbO, one of the most important parameters for X-ray photoconductors, and examined the underlying mechanisms responsible for charge generation and recombination. The X-ray sensitivity in terms of electron–hole pair creation energy, W±, was measured in a range of electric fields, X-ray energies, and exposure levels. W± decreases with the electric field and X-ray energy, saturating at 18–31 eV/ehp, depending on the energy of X-rays, but increases with the exposure rate. The peculiar dependencies of W± on these parameters lead to a conclusion that, at electric fields relevant to detector operation (~10 V/μm), the columnar recombination and the bulk recombination mechanisms interplay in the a-PbO photoconductor.

Abstract Background Lead is well known environmental pollutant, which can cause toxic effects in multiple organ systems. However, the influence of lead oxide nanoparticles, frequently emitted to the environment by high temperature technological processes, is still concealed. Therefore, we investigate lead oxide nanoparticle distribution through the body upon their entry into lungs and determine the microscopic and ultramicroscopic changes caused by the nanoparticles in primary and secondary target organs. Methods Adult female mice (ICR strain) were continuously exposed to lead oxide nanoparticles (PbO-NPs) with an average concentration approximately 106 particles/cm3 for 6 weeks (24 h/day, 7 days/week). At the end of the exposure period, lung, brain, liver, kidney, spleen, and blood were collected for chemical, histological, immunohistochemical and electron microscopic analyses. Results Lead content was found to be the highest in the kidney and lungs, followed by the liver and spleen; the smallest content of lead was found in brain. Nanoparticles were located in all analysed tissues and their highest number was found in the lung and liver. Kidney, spleen and brain contained lower number of nanoparticles, being about the same in all three organs. Lungs of animals exposed to lead oxide nanoparticles exhibited hyperaemia, small areas of atelectasis, alveolar emphysema, focal acute catarrhal bronchiolitis and also haemostasis with presence of siderophages in some animals. Nanoparticles were located in phagosomes or formed clusters within cytoplasmic vesicles. In the liver, lead oxide nanoparticle exposure caused hepatic remodeling with enlargement and hydropic degeneration of hepatocytes, centrilobular hypertrophy of hepatocytes with karyomegaly, areas of hepatic necrosis, occasional periportal inflammation, and extensive accumulation of lipid droplets. Nanoparticles were accumulated within mitochondria and peroxisomes forming aggregates enveloped by an electron-dense mitochondrial matrix. Only in some kidney samples, we observed areas of inflammatory infiltrates around renal corpuscles, tubules or vessels in the cortex. Lead oxide nanoparticles were dispersed in the cytoplasm, but not within cell organelles. There were no significant morphological changes in the spleen as a secondary target organ. Thus, pathological changes correlated with the amount of nanoparticles found in cells rather than with the concentration of lead in a given organ. Conclusions Sub-chronic exposure to lead oxide nanoparticles has profound negative effects at both cellular and tissue levels. Notably, the fate and arrangement of lead oxide nanoparticles were dependent on the type of organs.

The Pb oxide and Ru oxide films with various compositions were prepared by reactive sputtering using mixed gas of Ar and O2, and those anodic polarization properties were investigated in a 150 g L-1 H2SO4 solution at 303–333 K. When O2 amount of the Ar-O2 mixed gas was 25 vol.% or more, the product thin films were identified as mixed phase of α-PbO2 and β-PbO2 for the reactive sputtering of Pb target. On the other hand, the products were single phase of RuO2 for the reactive sputtering of Ru target at the same O2 amount of the mixed gas. The anode potential of the metallic Pb thin film was equal to that of the PbO2 thin film at the current density of 10 mA cm-2 or more. So, it can be judged that the surface of the Pb-based alloy anode was covered with the PbO2 at 60 mA cm-2, which is a typical current density during the operation of zinc electrowinning, and the oxygen evolution overpotential of the PbO2 determined the bath voltage of the electrowinning. Moreover, the anodic polarization measurement showed that the anode potential of the RuO2 at 60 mA cm-2 was about 560 mV lower than that of the PbO2. Therefore, the remarkable decrease of the anode potential for the Pb-based powder rolling anode, in which the RuO2 powders were dispersed in the Pb substrate, was probably due to an extremely low oxygen evolution overpotential of the RuO2 in itself.

Stress corrosion cracking (SCC) behaviors of Alloy 690 were studied in lead-containing aqueous alkaline solutions using the slow strain rate tension (SSRT) tests in 0.1M and 2.5M NaOH with and without PbO at 315°C. The side and fracture surfaces of the alloy were then examined using scanning electron microscopy after the SSRT test. Microstructure and composition of the surface oxide layer were analyzed by using a field emission transmission electron microscopy, equipped with an energy dispersive X-ray spectroscopy. Even though Alloy 690 was almost immune to SCC in 0.1M NaOH solution, irrespective of PbO addition, the SCC resistance of Alloy 690 decreased in a 2.5M NaOH solution and further decreased by the addition of PbO. Based on thermodynamic stability and solubility of oxide, high Cr of 30wt% in the Alloy 690 is favorable to SCC in mild alkaline and acidic solutions whereas the SCC resistance of high Cr Alloy 690 is weakened drastically in the strong alkaline solution where the oxide is not stable any longer and solubility is too high to form a passive oxide locally.

In this work a systematic investigation was carried out of the surface characterization and electrocatalytic activity of Ti/Ir0.3Ti(0.7-x)Pb x O2-coated electrodes (0

The reaction of oxidative coupling of methane (OCM) over PbO/SiO2 catalysts was studied in a flow reactor at 1050 K. The reaction mixture of CH4 and 02, diluted with He, was introduced directly into the reactor, or saturated with steam. Individual reactions of ethane, ethylene and carbon monoxide, in the presence or absence of oxygen, with or without the catalyst, were also investigated. After adding steam to the gas phase, methane conversion and selectivity toward C2 hydrocarbons increased. Ethane dehydrogenation to ethylene occurs through thermal cracking during the OCM reaction. The main source of CO In the OCM reaction is the oxidation of C2H4 in the gas phase. The CO2 formation in the OCM reaction occurs mainly from oxidation of adsorbed CO on the catalyst.

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