Addition Of PbO Research Articles

Myzus persicae resistance to neonicotinoids-unravelling the contribution of different mechanisms to phenotype.

Deciphering the mechanisms underlying insecticide resistance is key to devising appropriate strategies against this economically important trait. Myzus persicae, the green peach-potato aphid, is a major pest that has evolved resistance to many insecticide classes, including neonicotinoids. M. persicae resistance to neonicotinoids has previously been shown to result from two main mechanisms: metabolic resistance resulting from P450 overexpression and a targetsite mutation, R81T. However, their respective contribution to resistant phenotypes remains unclear. By combining extensive insecticide bioassays with and without addition of the synergist PBO, and gene copy number and expression quantification of two key P450 enzymes (CYP6CY3 and CYP6CY4) in a 23 clone collection, we, (i) confirmed that metabolic resistance is correlated with P450 expression level, up to a threshold, (ii) demonstrated that the R81T mutation, in the homozygous state and in combination with P450 overexpression, leads to high levels of resistance to neonicotinoids, and, (iii) showed that there is a synergistic interaction between the P450 and R81T mechanisms, and that this interaction has the strongest impact on the strength of resistance phenotypes. However, even though the R81T mutation has a great effect on the resistance phenotype, different R81T genotypes can exhibit variation in the level of resistance, explained only partially by P450 overexpression. To comprehend resistance phenotypes, it is important to take into account every mechanism at play, as well as the way these mechanisms interact. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Thermal degradation of polyvinyl chloride in the presence of lead oxide: A kinetic and mechanistic investigation

The elimination of toxic heavy metals from metallurgical wastes before its recycling to steel furnaces is essential. Lead oxide (PbO) is a major toxic heavy metal present in electric arc furnace dust (EAFD). The co-recycling of EAFD with Polyvinyl chloride (PVC) followed by water leaching allows the elimination of this material. Herein, an experimental and theoretical kinetic investigation was conducted on the thermal degradation of PVC in the presence of PbO. An inhibiting effect of PbO on the thermal degradation of PVC was observed; the onset PVC de-hydrochlorination temperature increased from 273 to 293 °C. PbO addition also increased the activation energy of PVC mass loss from 148 kJ/mol (PVC) to 173 kJ/mol (PbO-PVC) in the conversion window 5–45 %. The theoretical Density Function Theory (DFT) suggested that the intramolecular hydrogen transfer (IHT) to form H2O on PbO surface exhibited the highest energy barrier at 251.01 kJ/mol, which aligns with the experimental data. The kinetic parameters generated here can be utilised to calculate the appropriate holding temperature and time for the effective removal of PbO from waste EAFD using PVC as a chlorinating additive. This should contribute towards optimising process economics and efficiency.

SrO–ZnO–PbO–B2O3 glassy insights: Unveiling the structural and optical features for gamma ray shielding efficacy

The melt-quenching approach was utilised to synthesize amorphous SrO–ZnO–PbO–B2O3 glasses, with FTIR spectroscopy applied to the samples to reveal the various bonds' stretching and bending vibrations. With PbO introduced to the network, the UV–Vis absorption spectrum's absorption peak shifts towards the higher wavelength values, while Tauc plot analysis of the UV–Vis spectra reveals a 2.957–2.569 eV decrease in the band gap energy. The radiation shielding properties are examined via Phy-X program. The mass attenuation coefficient (MAC) has an inverse relation with the energy, which demonstrated the greater penetration ability of radiation that contains higher energy. In terms of the MAC values at low energies the results revealed a greater difference, while they are almost identical at higher energies. The linear attenuation coefficient (LAC) was evaluated and the chemical composition's influence discussed, with the LAC values in the order of SZPB1 <SZPB2 <SZPB3 <SZPB4. This confirms that the PbO addition leads to increased LAC values. The half value layer (HVL) decreases with increased concentration of PbO. This suggests that the higher the glass system's PbO content, the thinner the glass system needs to be to attenuate half of the incoming photons.

Studies on structural, optical, thermal and low energy shielding for gamma rays for the ZSBP glasses

By employing the melt-quenching technique, the ZnO–SrO–B2O3–PbO (ZSBP) glasses have been successfully fabricated. The derivative of Absorption Spectra Fitting (DASF) method was used to study the energy band gap (Eg) of the glasses which decreases from 3.57 eV to 3.39 eV. The structural properties have been studied using the Raman spectroscopy. The glass transition temperature (Tg) decreases with increase in concentration of the lead oxide. The current study examines the radiation shielding properties at 30.80–444 keV. The addition of PbO to the glasses resulted in a proportionate increase in the mass attenuation coefficient (MAC), suggesting a diminishing tendency in radiation transmission. At 30.80 keV, the MAC values are extremely high and range from 18.06 to 21.11 cm2/g. As density rises, the half value layer (HVL) decreases. In addition, the average HVL (HVL‾) decreases. The glass thickness required to reduce the radiation intensity to 90 %, 50 %, 25 %, and 10 % of its initial value is investigated at an energy of 35.80 keV. The T90 %, T50 %, T25 %, and T10 % values are 0.0020, 0.0132, 0.0264, and 0.0439 cm, respectively. The results suggest that a greater thickness of the radiation barrier is necessary to attain the necessary degree of attenuation.

Detailed investigations for mechanical and gamma-ray attenuation characteristics of B2O3-ZnO-BaO-TiO2 glasses doped with PbO

The effect of PbO addition with different concentrations on four synthesized zinc titanium borate glasses with the chemical formula xPbO-(75-x) B2O3-10ZnO-10BaO-5TiO2 (x = 30, 35, 40, and 45 mol%) was explored in this study. The partial PbO substitution for B2O3 increases the fabricated glasses' density by ≈ 20% from 5.31 to 6.37 g/cm3, respectively, with raising the PbO concentrations between 30 and 45 mol.%, respectively. Besides, the substitution mentioned above enhances the gamma-ray attenuation properties where the linear attenuation coefficient increased between 69.911 and 102.245 cm−1 (at 0.033 MeV), 0.341–0.415 cm−1 (at 1 MeV), and 0.200–0.262 cm−1 (at 10 MeV), increasing the PbO concentration between 30 and 45 mol.%, respectively. Simultaneously, increases in the PbO concentration within the fabricated glasses decrease the lead's equivalent thickness between 3.82 and 2.61 cm (at 0.033 MeV), 2.35–1.93 cm (at 1 MeV), and 2.81–2.14 cm (at 10 MeV). In contrast, substituting PbO for B2O3 compounds diminishes the fabricated glasses' mechanical properties, where the microhardness decreased by 13.5 % from 4.24 to 3.67 GPa. The lead equivalent thickness (Deq) values at 0.66 MeV were found equal to 2.410, 2.232, 2.078, and 1.945 cm, and at 1.112 MeV, these values were found equal to 2.222, 2.081, 1.956, and 1.829 cm for G1, G2, G3, and G4, respectively.

Overexpression of cytochrome P450 gene CYP6K1 is associated with pyrethroid resistance in German cockroaches (Blattodea: Ectobiidae) from California.

We investigated the expression of 4 cytochrome P450 genes (CYP4G19, CYP6J1, CYP6K1, and CYP4C21) in 4 field-collected strains (WM, RG386, CDR, and Ryan) of the German cockroach, Blattella germanica (L.), collected from California. The UCR susceptible strain was used as a comparison. Topical assays using a diagnostic dose (3× LD95) of deltamethrin revealed decreased sensitivity in all field-collected strains with mortality ranging from 0% to 58%, and the addition of PBO before deltamethrin treatment increased mortality to 52.5%-87.5%. Using qPCR to investigate the expression levels of CYP4G19, CYP4C21, CYP6J1, and CYP6K1, we found that only CYP6K1 was significantly overexpressed (2.1-5.8× higher) in all field-collected strains when compared to the UCR strain. Next, we investigated the role of the CYP6K1 gene by performing gene knockdown using RNAi. After dsCYP6K1 treatment, the expression levels of CYP6K1 in WM and Ryan strains were significantly reduced (P < 0.01) by 91%-94% vs. those treated with dsEGFP (control) on the third and sixth day posttreatment. RG386, CDR, and Ryan strains were more susceptible compared to their respective controls to topically applied deltamethrin 6 days after treatment with dsCYP6K1. This study provides evidence of the involvement of the P450 CYP6K1 gene in pyrethroid resistance in some populations of German cockroaches.

Effect of PbO on mechanical and radiations shielding properties of 70P2O3–5Al2O3–25Na2O glass system: A theoretical study

This study investigates the mechanical as well as shielding properties of 70P2O3–5Al2O3-(25-x)Na2O-xPbO, while using advanced MCNPX simulations code and Phy-X software. Advanced MCNPX coding simulation and online Phy-X software are used to compare the properties of three aluminum lead phosphate glasses named S1, S2 and S3 with PbO concentrations 0, 10, and 20 mol%, respectively. Various shielding parameters were calculated in the photon energy ranging from 0 to 15 MeV. These parameters include mass attenuation coefficient, effective atomic number, half-value layer, tenth-value layer, mean free path and linear attenuation coefficient. Our comparative analysis of the results from MCNPX and Phy-X in the case of mass attenuation coefficient indicates a high level of agreement, differing by less than 2% from each other. The half-value layer for S3 was found at 0.003 cm, 1.709 cm, and 5.984 cm at energies of 0.01 MeV, 0.5 MeV, and 15 MeV, respectively, while for S1 these values were found at 0.010 cm, 3.35 cm, and 13.96 cm in the same energy spectra. The results show that S3, with 20% PbO, is more likely to attenuate the gamma and X-ray photons; due to their minimum values of tenth value layer, half value layer, mean free path, and greater mass attenuation coefficient, effective atomic number as compared to S1 (undoped) and S2 (10% doped with PbO). The mass attenuation coefficient for S3 was found between 67.95 cm2/g to 0.030 cm2/g, while for undoped S1, these values varied between 27.64 cm2/g to 0.021 cm2/g in the energy range of 0–15 MeV. Furthermore, the Makishima-Mackenzie model is utilized to evaluate the mechanical behavior of our glass samples, influenced by factors such as energy of dissociation and packing density related to components of oxide. The mechanical features encompass various moduli, Poisson's coefficient and microhardness. The introduction of PbO in glass samples S2 and S3 increased all these properties, excluding Poisson's coefficient which decreases with the addition of PbO. Our findings provide valuable insights into the shielding and mechanical parameters of these glasses, suggesting probable applications in fields such as optics and nuclear physics.

Low‐temperature sintering Sm‐doped PMN–PZ–PT multilayer ceramic actuator with high strain and temperature stability

AbstractMultilayer ceramic actuators find extensive utility in applications requiring precise displacement control or force output, due to their advantages of high precision control, rapid response, low driving voltage, low power consumption, and so on. For practical applications, there is a need for high‐performance multilayer ceramic actuators (MLAs) that combine cost‐effectiveness, efficiency, and temperature stability. In this work, 1.5 mol%Sm‐doped 0.25 Pb(Mg1/3Nb2/3)O3–0.36PbZrO3–0.39PbTiO3 piezoelectric ceramics with PbO–CuO as sintering aid were fabricated. The addition of PbO–CuO significantly reduced the sintering temperature by 300°C, while having minimal impact on the piezoelectric properties. The optimized sintering condition, achieved at a low sintering temperature of 950°C with the introduction of a tiny 0.4 wt% sintering aid, yields impressive piezoelectric strain coefficient d33* = 690 pm/V. This substantiates the viability of employing low‐cost Ag/Pd (90/10) as inner electrode, which can be co‐fired with ceramic layer to fabricate MLA. This innovation enables a remarkable displacement of 1 µm at a low driving voltage of 200 V across a 9‐layers piezoelectric actuator, accompanied by high‐temperature stability, exhibiting &lt;20% variation over the temperature range of 30–250°C. These results underscore a great potential for high‐performance piezoelectric actuators over a broad temperature range.

BaO, ZnO, B2O3, PbO, and SiC effects on phosphorescent afterglow damping and thermal stability of SrAl2O4 base pigments at industrial glazes

Phosphorescent glazes are usually used in direction signs of emergency routes. That is why afterglow damping and thermal stability of phosphorescent pigments are the most decisive factors of phosphorescent glazes. This study aims to choose a suitable glaze to enhance the time and intensity of the afterglow. For this reason, the effects of BaO, ZnO, B2O3, and PbO additives on the afterglow intensity and lifetime of reference industrial glaze containing SrAl2O4 phosphorescent material were investigated. 5, 7, 10, 15, and 20 %wt SrAl2O4 phosphorescence powder was mixed with base industrial glaze to recognize the optimum component. Samples were fired at 1040 °C for 40 min in the same conditions and then were analyzed by photoluminescence spectroscopy. Results showed that increasing the SrAl2O4 proportion increased samples afterglow damping time, and 10 %wt SrAl2O4 was chosen as the optimum amount. Also, BaO is more efficient for increasing the intensity and afterglow lifetime. Moreover, 0.02, 0.03, 0.05, and 0.1 %wt SiC were added to the reference industrial glaze containing 10 %wt SrAl2O4 to investigate the reduction firing conditions on the glaze afterglow. Increasing the SiC ratio up to 0.02 %wt increased the afterglow lifetime from 5 ± 0.4 to 27 ± 1.7 min, but the afterglow intensity was decreased. Despite this, adding 0.03, 0.05, and 0.1 %wt SiC darkened the glaze and reduced the intensity and afterglow lifetime. The sample containing 0.1 %wt SiC did not melt properly, and this sample did not have any afterglow. Furthermore, the temperature required for firing affects the afterglow of the samples. On the other hand, to investigate the effect of temperature, the base industrial glaze containing 10 %wt SrAl2O4 was fired at 1040, 1120, and 1140 °C to determine thermal stability. The sample fired at 1140 °C had almost no phosphorescent afterglow. Also, dilatometry tests at the temperature of 600 °C and hot-stage microscope analysis were performed to determine the linear coefficient of thermal expansion and the melting point of the samples, respectively. The results showed the linear coefficient of thermal expansion of the industrial glaze with 10 %wt SrAl2O4 was 73.3 × 10−7 1/°C, and it could be changed between 58.5 × 10−7 1/°C by adding 10 %wt B2O3 to 73.5 × 10−7 1/°C by adding 10 %wt BaO. The melting point of the pure industrial glaze was 1130 °C, and adding 10 %wt, SrAl2O4 decreased it to 1076 °C. Also, by adding 10 %wt BaO, ZnO, B2O3, and PbO to phosphorescent glaze, melting point was obtained 1128 °C, 1020 °C, 1030 °C, and 974 °C respectively. The same sample with 0.02 %wt SiC melted at 1154 °C.

Comprehensive study of optical, thermal, and gamma-ray shielding properties of Bi2O3–ZnO–PbO–B2O3 glasses

Abstract The Bi2O3–ZnO–PbO–B2O3 (BiZPB) glasses are prepared using the melt-quenching technique. As the concentration of lead oxide increases, the band gap energy (E g) decreases from 2.864 to 2.671 eV. The BiZPB glasses exhibit remarkable stability under thermal stress, as indicated by the thermogravimetric analysis graph, with only a marginal 0.5% loss in their initial mass. The decrease in the glass transition temperature (T g) of BiZPB glasses, with an increase in the PbO concentration, can be attributed to the specific influence of PbO on the glass structure and properties. The radiation shielding performance for the prepared glasses is evaluated using Phy-X software. The transmission factor (TF) for the 10B2O3–10ZnO–40PbO–40B2O3 glass sample is almost zero at 0.122 MeV, which means that this glass sample can attenuate almost all the photons with an energy of 0.122 MeV, whereas the TF values for this sample with thicknesses of 0.5 and 1 cm are 88 and 77%, respectively., it can be observed from the TF values that the prepared glasses have good attenuation performance against low energy (0.122, 0.245, and 0.344 MeV), while they have weak shielding performance against high energy radiation. The addition of PbO causes a reduction in TF, which means that the addition of an extra amount of PbO into the glasses results in an enhancement in the radiation shielding competence of the samples. The average half-value layer ( HVL ̅ \bar{{\rm{HVL}}} ) is also calculated. The results demonstrated that HVL ̅ \bar{{\rm{HVL}}} is at its lowest between 0.248 and 0.411 MeV, ranging between 0.396 and 0.513 cm.

Stable two-dimensional tin-based perovskites for warm-white light emitters

Two-dimensional (2D) Sn-based organic-inorganic hybrid perovskites are useful materials for white light emitters due to their super high fluorescence efficiency and higher stability when compared to their three-dimensional (3D) counterparts. Herein, 2D Ruddlesden-Popper (RP) perovskites (BA)2Sn(Br1-x Ix)4 (BA = n-butylammonium, x: 0–1) were prepared and regulated using halogen doping. As iodine content increased, the band gap of (BA)2Sn(Br1-xIx)4 was finely regulated from 2.35 eV to 2.0 eV, thereby tuning the photoluminescence from yellow to red with relatively high PLQY exceeding 40 %. The use of small amounts of Pb2+ to stabilize Sn2+ through the addition of PbO in the precursor solution resulted in high air- and photo stable (BA)2Pb0.1Sn0.9(Br–I)4 phosphors with bright yellow to red light. The mixture with (BA)2PbBr4 (blue light phosphor) followed by excitement by UV LED chips (285 nm) resulted in cold and warm white Sn–Br–I perovskite LEDs. The CIE coordinates and correlated color temperature (CCT) indicated Br0.4I0.6 LED as an ideal warm-white emitter with suitable CIE (0.352, 0.330) and CCT (4376.3 K). The prepared white LEDs showed high photo and air stability without significant luminescence decay (<5 % relative) under continuous UV light excitation over 200 min and exposure to air for 3 months.

High transparency of PbO–BaO–Fe2O3–SrO–B2O3 glasses with improved radiation shielding properties

This study investigated the role of PbO and BaO on the optical and radiation shielding properties of PbO–Fe2O3–SrO–B2O3–BaO glass systems. Optical studies indicate that the prepared glass samples are transparent within the visible spectrum; the transparency increases marginally with increasing PbO/BaO concentrations. Furthermore, by increasing the PbO/BaO ratio, the BO4 units increase (BO3 units decrease), and the density values increase. In addition, the optical band gaps widen, and linear and nonlinear refractive indices decrease. The reductions in nonbridging oxygen were responsible for the increased band gaps and decreased refractive index behavior. Moreover, the ionizing radiation shielding studies showed improved behavior with additional PbO additives. Also, the HVL values of the present glass samples are comparatively lower than the HVL of some standard ionizing radiation shielding materials. Finally, the combination of effective radiation shielding properties and high transparency makes the current glass samples good candidates in the ionizing radiation shielding field.

An exploration of the physical, optical, mechanical, and radiation shielding properties of PbO–MgO–ZnO–B2O3 glasses

Abstract This study presents the results of an investigation into the physical, optical, and mechanical characteristics of glasses prepared from a mixture of ZnO, MgO, B2O3, and PbO. It was found that increasing the concentration of PbO in the glasses led to an increase in both the density (ρ) and molar mass (M). The addition of PbO also affected the packing arrangement of oxygen atoms in the glass network, resulting in changes to the oxygen molar volume (V o) and oxygen packing density. Furthermore, the investigation found that the optical basicity (Ʌ th) of the glass elevated with increasing PbO concentration. Finally, the behavior of the average electronegativity (χav) and electronic polarizability ( α o − 2 {\alpha }_{{\rm{o}}}^{-2} ) with respect to the concentration of PbO in the glasses is discussed, whereby the addition of PbO affected the glasses’ mechanical characteristics as follows: (i) the addition of PbO increased the complexity of the glass network by enhancing the average cross-link density ( n c ̅ \bar{{n}_{{\rm{c}}}} ) and the number of bonds per unit volume of the glasses (n b); (ii) the glasses’ Young’s modulus (E), bulk modulus (B), and shear modulus (G) declined as the mol percent of the PbO increased; (iii) the longitudinal modulus (L) reduced but remained greater than G; (iv) the glass network cross-linking reduced the Poisson ratio (σ); (v) the glasses’ fractal bond connectivity (d) values indicated a three-dimensional network; and (vi) lead oxide hardened the glass, suggesting that a stronger structure manifests. These findings collectively demonstrate that PbO improves the rigidity and interconnectivity of glass. The gamma radiation-shielding characteristics of the glasses were evaluated using the Phy-X software in the 0.015–15 MeV energy range. The radiation-shielding properties of the studied glasses can be compared with other materials by introducing a new parameter known as the radiation coefficient ratio (R). It is observed that Q4 glass sample had superior shielding performance.

Newly-formulated zinc-bismuth-barium-sodium-silicate glass system with lead oxide addition: Probing radiation shielding characteristics via triple methodology

In recent times, glass materials appear to be strong candidates for radiation protection applications. In this study, a zinc-bismuth-barium-sodium-silicate (ZBBSS) glass system with a formulation of 10ZnO – 20Bi2O3– 5BaO – 15Na2O – (50-x) SiO2– xPbO, x: 0, 5, 15 and 25 wt% was synthesized. The traditional melting technique (1325–1375 °C) enabled the synthesis of four different glass samples coded ZBBSS1 to ZBBSS4. Following synthesis, Archimedes' principle, XRD, FTIR, UV-Vis, and DSC techniques showed physical, structural, optical, and thermal property alterations as a function of PbO inclusion, while the triple methodology (experimental, theoretical, and simulation) revealed radiation attenuation aspects in a broader sense. According to the findings, ZBBSS1 had density of 3.1107 g/cm3 while the other samples had density values of 3.2285, 3.6053, and 4.0158 g/cm3 in respective order. The clear existence of non-crystalline structure for the ZBBSS glass series was reported. Similar vibrational modes were found for ZBBSS glass systems, and -OH, Si-OH, Si-O-Si, and Pb-O-Pb bonding types were assigned to peak formations. For determination of thermal properties, it was observed that Tg became lower, from 520.6 to 392.4 °C, in parallel to the increment in the PbO doping rate. Additionally, an increase in the PbO doping rate hindered the transmission phenomenon based on UV-Vis spectra. Gamma absorption coefficients were measured at six energies with four sources using the gamma spectroscopic system. The measured values were compared with the FLUKA code and Phy-X software. Experimental LAC values of 0.2463, 0.2729, 0.3064, and 0.3618 cm−1 were measured using a Cs-137 source for the ZBBSS glass series, respectively. The variation in the values obtained with the triple methodology overlapped with each other for all energies. Among the prepared glasses, the best LAC and MAC, thinnest HVL, lowest MFP and TF were determined for ZBBSS4 glass sample with maximum PbO content. From the results obtained, it is concluded that the addition of PbO is a useful way to improve the gamma attenuation capacity, and among the glasses examined, ZBBSS4 had superior protection against gamma rays.

Improvement in the superconducting properties of YBa2Cu3O7-d material via PbO addition

Improvement in the superconducting properties of YBa2Cu3O7-d material via PbO addition

Microstructure, electronic transitions and UV transparency of K2O–B2O3–Sm2O3 glass via PbO additives

Samarium-doped borate glass is widely used in solid-state devices due to their suitable refractive index and appealing spectral characteristics. Here, we used the melt quenching technique and characterized the microstructure, optical absorption, electronic transitions and non-linear optical parameters of K2O-borate glass doped with a constant amount of Sm2O3 (1.8 mol %) and different amounts of PbO (0, 5, 10, 15 and 20 mol %), primarily using Fourier-transform Infrared (FTIR) and optical absorbance. FTIR results confirmed the strong influence of PbO on the glass internal structure. Further, inspecting the optical absorption, we found the following results. The optical absorption bands at 401, 475, 935, 1073, 1226, 1369, 1468, 1528, and 1942 nm are recognized to Sm3+ cation's electronic transitions from 6H5/2 (ground state) to 6P3/2, 4I11/2, 6F11/2, 6F9/2, 6F7/2, 6F5/2, 6F3/2, 6H15/2 and 6H13/2 states respectively. Furthermore, for the PbO-free glass sample, an absorption band we observed at ∼220 nm in the UVC-domain. Moreover, this PbO-free glass sample is transparent in the rest of the UV-regions. A broad absorption band starts to appear with increasing the PbO concentrations in the glass system. The broadening of this band increased with further PbO additions. This band was attributed to Pb2+ cations with 6s2 species that absorb sturdily in the UV-domain. More, the glass sample doped with the highest PbO concentrations (20 mol %) can be considered a UVA transparent material, blocking UVC and UVB. Also, we found the values of Urbach energy, non-linear refractive index, third-order non-linear susceptibility, and refractive index increased for additional PbO contents, which is attributed to the increased disorder in the glass matrix. Furthermore, the results propose that the PbO-free glass sample can be used as UV-transparent material in optical applications. On the other hand, the glass sample that contains the highest PbO concentrations (20 mol %) can be used as a glass filter in some optical applications that permit UVA to pass and block UVC and UVB radiations.

Electrical properties of tin oxide based varistors with PbO addition in humid air

In order to decrease the humidity sensitivity of SnO2–Co3O4–Nb2O5–Cr2O3 varistor ceramics, lead oxide was added and the electric characteristics of synthesized materials with the PbO concentration of 0, 0.1, 0.5, 0.7, 1 and 2 mol.% in the air with relative humidity of 10–86% were investigated. All tested samples have non-linear current–voltage characteristics with large values of the nonlinearity coefficient of 38–51. The optimal concentration of PbO addition in ceramics is 0.5–0.7 mol.%. The addition of such quantity of lead oxide to the ceramics leads to the decrease of the breakdown electric field up to 4390 V/cm and the humidity sensitivity coefficient up to 172. The increase of the PbO concentration provides the increase of the electrical conductivity of samples at low fields. The barrier mechanism of electrical conductivity of the studied ceramics is proved by the obtained values of potential barrier heights of 0.85–0.90 еV on the SnO2 crystallite boundaries.

Exploring the impact of PbO/CdO composition on the structural, optical, and gamma ray shielding properties of dense PbO–TeO2–CdO glasses

Through the melt-quenching process, thick, transparent, and light yellow PbO–TeO2–CdO glasses were fabricated, with sample densities ranging from 5.576 to 6.082 g/cm3. X-ray diffraction (XRD) spectra showed that the material was amorphous, while Fourier transform infrared (FTIR) spectra demonstrated multiple bond stretching modes and vibrational frequencies. With an increase in the mol% of PbO concentration, the derivative of absorption spectra fitting (DASF) method showed a reduction in the bandgap energies to 3.520 eV, 3.457 eV, 3.433 eV, and 3.394 eV for Pb70, Pb72.5, Pb75, and Pb77.5, respectively. For the Pb70 and Pb77.5 glasses, the transmission factor (TF) decreased with thickness. The Pb77.5 glass had the highest radiation protection efficiency (RPE), with an RPE range of 66–70% for a thickness of 1.25 cm. Moreover, the addition of PbO improved the transparency, density, and gamma-ray shielding abilities of the glasses.

Impact of lead oxide on the structure, optical, and radiation shielding properties of potassium borate glass doped with samarium ions

In this work, the radiation shielding ability and the high transparency of glasses are combined. Glass systems with the formula xPbO-(79-x)B2O3 + 19.2 K2O+ 1.8Sm2O3 with x = 0, 5, 10, 15, and 20 mol% were prepared using the melt-quenching method. Also, the optical transmittance was examined in wavelengths between 200 nm and 800 nm. An increase in average density was observed with further PbO additions. In detail, the density values increased from 2.361 to 3.027 g/cm3 with further PbO additions. The optical transmittance of these glasses indicates that all glass samples have good transparency. In detail, the PbO-free glass sample exhibits the maximum transmittance, around 73 %, in the wavelength range of 500–600 nm. While the transmittance of the glass sample containing 20 mol% of PbO is 60–62 % in the 500–600 nm wavelength range. The optical band gap (Eg) values of these glasses were obtained using the absorption spectrum fitting (ASF) method. The Eg values showed decreasing behavior with PbO additions. Also, the radiation shielding parameters are much higher than some common and standard glasses and materials used to block radiation. Based on these findings, the present glasses are good candidates for use as shielding materials in the radiation shielding field.

Giant piezoelectric properties of the [110]-oriented PZT-5H single crystals grown by solid state crystal growth

An ultrahigh piezoelectric performance (d33 ∼ 1800 pC N−1 and ∼ 2400 pm V−1 at 3 kV cm−1, k33 ∼ 87%) is achieved in the [110]-oriented PZT-5H single crystals grown using the solid state crystal growth method with excess PbO addition.