Amount Of PbO Research Articles

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.

Determination of X-ray and gamma-ray shielding capabilities of recycled glass derived from deteriorated silica gel

We determined the radiation shielding properties for 10CaO–xPbO–(90-x) deteriorated silica gel (DSG) glass system (x = 20, 25, 30, 35, 40, and 45 mol.%). The mass attenuation coefficient (MAC) has been estimated at photon energies of 74.23, 97.12, 122, 662, 1173, and 1332 keV using a narrow beam X-ray attenuation and transmission experiment, the XCOM program, and a PHITS simulation. The obtained MAC values were applied to estimate the half value layer (HVL), mean free path (MFP), effective atomic number, and effective electron density. Results show that the MAC value of the studied glasses ranges between 0.0549 and 1.4415 cm2/g, increases with the amount of PbO, and decreases with increasing photon energy. The HVL and MFP values decrease with increasing PbO content and increase with increasing photon energy. The recycled glass, with the addition of PbO content (20–45 mol.%), exhibited excellent radiation shielding capabilities compared to standard barite and ferrite concretes and some glass systems. Moreover, the experimental radiation shielding parameters agree with the XCOM and PHITS values. This study suggests that this new waste-recycled glass is an effective and cost-saving candidate for X-ray and gamma-ray shielding applications.

Composition Classification of Korea Ancient Glasses by Using Raman Spectroscopy

In this study, investigated the possibility of quantitatively and qualitatively analyzing Korean ancient glasses via Raman Spectroscopy. We subjected four categories of Korean traditional glasses, namely, lead-BaO, lead, potash, and soda glasses (3, 3, 10, and 10 pieces, respectively), to this analytical technique. The results showed significant differences between the stretching and bending Raman vibration regions corresponding to these different Korean ancient glass types. Specifically, the stretching vibration regions corresponding to lead-BaO and lead glasses showed peaks at 1040 and 1000 cm-1, respectively; the stretching vibration region of normal glass appears at 1100 cm-1. The bending vibration regions corresponding to potash and soda glass showed Raman peaks at 490 and 560 cm-1, respectively. Furthermore, the Raman spectra of the lead and lead-BaO glasses showed red shifts, which depended on the amount of PbO present. Thus, our findings highlighted the possibility of quantitatively determining the amount of PbO, a major component of lead glasses, via Raman Spectroscopy.

Regulation of lead oxide on Cyaniding Behavior of chalcopyrite

During the cyanidation of gold‑copper ores and concentrates, the chalcopyrite significantly increases cyanide consumption. The effects of PbO on the chalcopyrite dissolution mechanisms were studied by SEM and XPS analyses during cyanation. A small amount of PbO could promote the dissolution of chalcopyrite, while more PbO would inhibit dissolution. When 0.5 g/L PbO was added, the main lead compound on the surface of chalcopyrite was PbS, which could enhance the electron transfer between cyanide and chalcopyrite, thus facilitating the dissolution of chalcopyrite. The amount of PbS precipitates increased in the leaching system when the amount of PbO was more than 0.5 g/L. This reduced prominently the free sulfide ions concentration in the solution. PbS would be oxidized to form thiocyanate and lead (II) ions when the concentration of sulfur ions decreased continuously in the solution. These lead (II) ions would react with OH– to form Pb(OH)2 precipitates, which attach to the surfaces of chalcopyrite and inhibit its dissolution in cyanide solutions. The developed method can not only improve the leaching rate of gold but also reduce the consumption of reagents.

2018-2019 Kazı Sezonlarında İznik Çini Fırınları Kazısı’nda Ele Geçen Baskı Dekorlu Seramiklerin ve Seçili Örnekler Üzerinden pXRF Cihazı ile Yapılan Analiz Sonuçlarının Değerlendirilmesi

Iznik reached the peak of its ceramic and tile production between the 14th- and 17th- centuries. Recent findings at the Iznik Tile Kilns Excavation carried out in the BHD coded excavation area in Iznik District center revealed that ceramics had been produced there using an impressed/moulded technique , which was widely used in non-Anatolian Islamic ceramic art. These types of ceramics, which are thought to have been intensively produced after Iznik passed into Ottoman administration in 1331, were classified into two main groups in terms of their forms and decorations. Moreover, during the 2019 excavation season, characterization studies were carried out using a portable XRF (pXRF) instrument on seven selected samples in order to determine the body, slip and glaze composition. The results showed that the sample without a slip contained calcium-rich clay (high calcium and high alumina). The analyses of the molding materials confirmed earlier studies which had determined that the paste used (the third type of paste) had been calcareous or calcium-rich clay. Moreover, the sample with slip contains a greater amount of quartz (55.4 wt%) than the sample without slip (44.2 wt%). Of interest is that the sherd which is covered with a turquoise glaze contains 24.6 wt% lead-oxide (PbO) and 6 wt% tin oxide (SnO2 ). This glaze composition may indicate that the artifact was produced in the earlier period of Iznik production, namely at the end of the 15th century. Another glazed mold from among the samples analysed does not contain any tin oxide and has a higher amount of PbO which indicates a later production date (17th- century). The pXRF measurement results suggest that the mold may have been produced in an earlier period, and then glazed later for decorative and/or technical purposes.

Lead oxide/carbon black composites prepared with a new pyrolysis-pickling method and their effects on the high-rate partial-state-of-charge performance of lead-acid batteries

A new pyrolysis-pickling method was developed to prepare various lead oxide (PbO)/carbon black (CB) composites as the additives in the negative plates of lead-acid batteries to improve their high-rate partial-state-of-charge (HRPSoC) performance. Compared with CB, the PbO/CB composites prepared by the pyrolysis-pickling method have higher content of alkaline surface functional groups (Calkaline) and less content of carboxyl surface functional groups (CCOOH) on CB particles which are still covered with small amount of PbO, meanwhile they have smaller BET surface area, but larger pore volume and average pore width. The hydrogen evolution process in the negative plates containing the PbO/CB composites is inhibited effectively due to the increased Calkaline on CB, while the redox processes (Pb↔PbSO4) in these negative plates are accelerated obviously owing to the changes in their microstructure. The PbO/CB composites can impede the growth of PbSO4 crystals and significantly increase the HRPSoC cycle life of the simulated test cells. In general, the PbO/CB composites with a lower PbO content may be the appropriate additives for the negative plate of lead-acid batteries.

Effect of Glass-Phase Design on the Dielectric Properties of PbO-SrO-Na2O-Nb2O5-SiO2 Glass–Ceramic

The effect of glass-phase design on the dielectric properties of PbO-BaO-Na2O-Nb2O5-SiO2 glass–ceramic has been investigated. The glass phase of 36Na NbO3-18(Pb0.6Sr0.4) Nb2O6-46SiO2 glass–ceramic was modified by addition of lead ions, which is expected to optimize the dielectric properties of the SiO2 glass, thus improving the performance of the glass–ceramic composite. Phase composition and dielectric behavior were systematically investigated. Dielectric properties varied as a function of the amount of PbO added. The dielectric constant increased from 515 to 648 when 10 mol.% lead ions (relative to the SiO2 glass) was added to the glass phase. Dielectric breakdown strength also increased slightly, from 5.1 to 7.8 kV/mm, suggesting glass-phase design could be an efficient way of optimizing the dielectric properties of glass–ceramic composites.

Glassy faience from the Hallstatt C period in Poland: a chemico-physical study

Beads and pin heads made of glassy faience, often decorated with true glass, discovered at seven different cemetery sites in Poland and dated chiefly to the Hallstatt C period (c. 750/700–600 BC), were examined by the LA-ICPMS and EPMA methods. The analysis involved 48 samples from 39 objects. The main objectives were: (i) to characterize the glassy faience in terms of the physical structure and chemical composition of the glass; (ii) to evaluate differences in the chemical composition of the glass forming the glassy faience; (iii) to examine the chemical composition of the true glass in the decoration on objects made of glassy faience. Glassy faience was found to be made of glass and numerous quartz grains, inclusions and gas bubbles. Manifest in the true glass of the decoration were numerous minor inclusions of the colorant, represented mostly by a compound of lead and antimony. Two groups of glass forming glassy faience were distinguished based on the differences in chemical composition: LMMK and LMGGF. The first is characterized by a moderate concentration of K2O (average 2.7%), high Al2O3, Fe2O3 and some trace elements (e.g. B and Ti). The second has a generally lower content, compared to LMMK, of K2O, Na2O, Al2O3, Fe2O3, B2O3 and TiO2, but higher PbO and Sb2O5. True glass LMG contained little K2O, Al2O3, B2O3 and TiO2, but a large amount of PbO and Sb2O5. All of the glasses had a low content of CaO and MgO. LMMK glass was melted using sand and a flux that could not be easily identified (plant ash?), whereas LMGGF and LMG glass used sand and natron. The glassy faience is usually blue and was colored with cobalt compounds. The yellow glass of the decoration was colored with lead antimonate.

Effect of excess PbO on the microstructures and electric field induced strain of Pb0.97La0.02(Zr0.63Sn0.26Ti0.11)O3 antiferroelectric ceramics

Microstructures and electrical properties of ( Pb 0.97 La 0.02)( Zr 0.63 Sn 0.26 Ti 0.11) O 3 (PLZST) antiferroelectric (AFE) ceramics with different PbO content were investigated in this study. X-ray diffraction analysis showed that with the increase of PbO amount, the stability of AFE phase reduced due to the decrease of lead vacancies. Besides, it was observed that the sintering properties could be improved by adding a small amount of PbO . Further, the electric field induced polarization and strain first increased, and then decreased with increasing PbO addition and they showed good frequency stability at low frequency. The maximum strain of 0.65% was obtained in the specimens with 8 mol% PbO content at the frequency 1 Hz. Both a high strain level and relatively good frequency stability in this composition can make a potential candidate for actuators applications over a wide-frequency working range.

Recording lead Mα line in rare-earth phosphates using a JEOL JXA-8100 microanalyser

Conditions of recording the Pb Mα line and the background in monazite age dating are studied on an example of simple synthetic rare-earth phosphates. By selecting cutoff thresholds, pulses were discriminated from the radiation superimposing on the analytical signal in the highest orders of reflection. The interfering lines are Y Lγ2,3, Th Mζ1, and Th Mζ2. High-aperture and standard spectrometers of the microanalyser do not ensure the complete resolution of Th radiation with the Pb Mα line, and its software allows the analyst to take into account the superposition of only one element. The contribution of interfering radiation is insignificant: the presence of 1% Y2O3 or ThO2 results in the overestimation of PbO by ∼0.009 and 0.002%, respectively. The nearest free regions for measuring background are at ±4.5 mm from the Pb Mα line. Using the background measured in the short-wave region systematically underestimates the amount of PbO by 0.098 wt %. Measurements on the other side lead to overestimation by 0.061%. Calculations of the average background value are more preferable and underestimate the results by approximately 0.019%. To decrease the error more, one should record a spectrum for the determination of its bremsstrahlung component under the lead line.

Influence of PbO and TiO2 additives on the microstructure development and magnetic properties of Ni–Zn soft ferrites

This paper focuses on the effect of PbO and TiO2 on the magnetic properties and microstructural development of Fe2Ni0.64Zn0.36O4 soft ferrite. Ferrite was added to these oxides, ranging from 0 to 3.2wt% in steps of 0.4wt%. The results showed that with increasing the amount of PbO up to a certain percentage, relative density, grain size and magnetic permeability increase and then decrease. This additive caused to increase DC-resistivity, power loss and decrease in magnetic permeability and saturation magnetization. TiO2 revealed no considerable effect on the grain growth and densification. In contrast this additive due to the doping of the high valent Ti4+ ions to the lattice affects the magnetic and electrical properties noticeably. TiO2 improved the loss properties (up to 1.2wt%) and magnetic permeability (up to 2.0wt%) but reduced the saturation magnetization, and DC-resistivity of ferrite.

The Effect of Excess PbO on Crystal Structure, Microstructure and Dielectric Properties of (Pb0.50Sr0.50)TiO3 Ceramics

Lead strontium titanate [(Pb50Sr50)TiO3; PST] ceramics were fabricated by the conventional solid state reaction method using calcination and sintering temperatures of 950°C and 1250°C. To prevent PbO evaporation during the firing processes, excess PbO was added to the samples in varying amounts from 0–10 wt.%. It was found that PST powders indexed in a tetragonal structure. Impurity phases were detected in the calcined powders which had excess PbO higher than 3 wt%. A pure perovskite phase was obtained from all ceramic samples. The lattice parameters a, c and the c/a ratio decreased with an increasing excess of PbO. The average particle size and the average grain size increased with the increase of PbO. The porous microstructure slightly decreased with an increasing amount of PbO, up to 1 wt.%, then slightly increased with higher excess PbO. The density can be improved by adding 1 wt.% of excess PbO. The dielectric constant increased from 7500 for the 0 wt.% sample to 8300 for the 1 wt%. This was followed by reductions for 3, 5 and 10wt.%. The Curie temperature and transition enthalpy slightly increased with an increase amount of PbO until 1 wt.%, then slightly decreased, for the higher excess PbO.

The influences of firing temperatures and excess PbO on the crystal structure and microstructure of (Pb0.25 Sr0.75)TiO3 ceramics

Polycrystalline samples of (Pb0.25Sr0.75)TiO3 (PST75) were prepared by the solid-state reaction method. The effects of firing temperatures and excess PbO on PST75 ceramics were investigated. The PST75 was calcined between 600 and 1000 °C for 3 h and the sintering temperature ranged between 1050 and 1250 °C for 2 h. The optimized calcination and sintering conditions were identified as 950 and 1250 °C, respectively. The lattice parameter c increased, while the lattice parameter a decreased with increased firing temperatures. The average particle size and average grain size increased with increased firing temperatures. After the addition of PbO—excess 0, 1, 3, 5, and 10 wt%—in the PST75 samples, the lattice parameter a decreased. The average particle size and the average grain size increased with the increase of PbO. The porous microstructure slightly decreased with an increasing amount of PbO—up to 3 wt%—then slightly increased with the higher excess PbO. The density was improved by adding 3 wt% of excess PbO. A low dielectric loss was observed from the 3 wt% excess PbO sample.

Magnetic and dielectric proprieties of multiferroic (1-x)Pb(Fe2/3W1/3)O3 -XPbTiO3 Ceramics prepared via a modified two-stage solid-state reaction

Multiferroic Pb(Fe2/3W1/3)O3-PbTiO3 (PFW-PT) ceramics were synthesized via a modified two-stage solid-state reaction. This method utilized Fe2WO6, prepared at a first-stage, which was subsequently reacted with a stoichiometric amount of PbO and TiO2 at the second stage. This procedure efficiently suppressed the formation of lead tungstates and leads to getting dense ceramics. Electric and dielectric properties of (1-x)Pb(Fe2/3W1/3)O3 -xPbTiO3 solid solutions were investigated as a function of the frequency and temperature. All samples present density higher than 96% of the theoretical one, low percentage of pyrochlore phase (<2%) and relatively high electrical resistivity (<1010 Ω.m). RF dielectric measurements over the temperature showed the presence of a peak, which is related to the ferro-paraelectric phase transition and conductive contributions (in the range 200-700 K), associated to a electronic hoping mechanism. The dielectric properties of the PFW shows a typical relaxor behaviour for x = 0 and 0.10 with frequency-dependent peak temperature (Tm), while the samples with higher PT-content undergo a 'normal' para-ferroelectric transition at the Curie temperature TC.The FE phase transition of PFW is shifted to higher temperatures by PbTiO3 (PT) additions and high resistivity are obtained for PT containing samples. Different types of magnetic activity dependent on composition and temperature were found.

Two-photon absorption in TeO2-PbO glasses excited at 532 and 590 nm

Degenerate two-photon absorption (TPA) in a binary glass with composition TeO2-PbO is reported. The TPA coefficient, α2, obtained with nanosecond laser pulses at 532 and 590 nm, increases when the relative amount of PbO is increased. The maximum TPA coefficient, α2= 12.6 cm/GW, is comparable to or larger than the values reported for crystalline semiconductors and other recently reported glasses.

PIEZOELECTRIC AND DIELECTRIC PROPERTIES OF LOW TEMPERATURE SINTERING PMN-PZN-PZT CERAMICS ACCORDING TO THE AMOUNT OF PbO

ABSTRACT In this study, in order to develop the composition ceramics for low loss multilayer piezoelectric actuator, Pb x [(Mn1/3Nb2/3)0.07(Zn1/3Nb2/3)0.06(Zr0.48Ti0.52)0.87]O3(abbreviated as PMN-PZN-PZT) ceramics were fabricated according to the amount of PbO, using two-stage calcinations method and conventional mixed oxide process. And also, their dielectric and piezoelectric properties were investigated. Excess PbO improved all the dielectric and piezoelectric characteristics due to the enhancement of sinterability. At the PbO of 1.00 mol and sintering temperature of 930°, the properties of specimen showed the optimum values of density = 7.79 g/cm3, εr = 1274, kp = 0.553, Qm = 1576, d33 = 318 pC/N, respectively for low loss multilayer piezoelectric actuator application.

PbO량에 따른 저온소결 PMN-PNN-PZT 세라믹스의 유전 및 압전특성

In this study, in order to develop multilayer ceramics vibrator for ultrasonic nozzle, PMN-PNN-PZT ceramics were fabricated using <TEX>$Li_{2}CO_{3}-Na_{2}_CO_{3}$</TEX> as sintering aids and their piezoelectric and dielectric characteristics were investigated according to the amount of PbO. With increasing PbO contents, secondary phases were increased and phase structure was changed from tetragonal structure to rhombohedral structure and also electromechanical coupling factor was linearly decreased. At the composition ceramics with the sintering temperature of <TEX>$870^{\circ}C$</TEX> and 1 mol% excess PbO, density, electromechanical coupling factor, dielectric constant, piezoelectric d constant and mechanical quality factor showed the optimum value of <TEX>$7.879\;g/cm^{3}$</TEX>, 0.55, 1149, 328 pC/N, 1224, respectively for multilayer ceramics vibrator application for ultrasonic nozzle.

Effect of lead content on the structure and piezoelectric properties of hard type lead titanate–zirconate ceramics

In the present investigation we studied the effect of lead content on a hard type ceramics starting from lack to excess PbO. Specimens of Pb x (Mn 0.017Sb 0.033Zr 0.48Ti 0.47)O 3 with 0.96 ≤ x ≤ 1.06 were prepared by conventional oxide mixing technique and sintered at temperatures between 1280 and 1350 °C. In samples with lower Pb concentration the pyrochlore phase appeared, while in those with higher Pb an excess of PbO phase was detected. These phases proved detrimental for the properties of sintered ceramics. The highest values of piezoelectric properties were observed only for samples with an excess lead of about 2% sintered at 1340 °C, indicating that it represents the optimum amount of PbO. For such samples, the density ρ was 7.77 g/cm 3, the remnant polarization P r was 37 μC/cm 3 the planar coupling coefficient k p was 0.57 and the charge constant d 33 was 340 pC/N.

Thermal and structural characterization of the vitreous samples in the SiO2 - PbO - Na2O system

Lead-containing glasses have been used from the ancient time. Recently, due to the possible application in optics, electronics, nuclear techniques, wastes inactivation. the interest in these types of glasses has been renewed. For lead waste inactivation, glasses with high amount of PbO in the composition are required, those exhibiting at the same time a high chemical and thermal stability. Thermal behavior of lead-silicate glasses was examined by differential thermal analysis (DTA). Infrared spectroscopy was used to investigate the structure of the glasses. The spectra were interpreted in terms of the structures of silicate group by comparison with the spectra of other silicate crystals. The DTA and infrared data were correlated with the chemical stability tests.

Synthesis and characterization of Pb–Bi bimetal nanoparticles by solution dispersion

In this paper, we report a new solution synthetic route to prepare Pb–Bi bimetal nanoparticles from bulk ingot that is different from conventional solution methods. The Pb–Bi nanoparticles were prepared by dispersing directly melt Pb–Bi ingot in a suitable solvent and characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and other techniques. Transmission electron microscopy shows that the Pb–Bi nanoparticles appear a spherical shape with an average diameter of 50 nm. X-ray diffraction studies show that the Pb–Bi nanoparticles contain crystalline Pb 7Bi 3, Bi and a little amount of PbO. Tribological results show that Pb–Bi nanoparticles as a lubricating additive show good antiwear properties. In addition, the formation mechanism of the Pb–Bi nanoparticles was also discussed.