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1.
2.
《Ceramics International》2023,49(19):30915-30923
B2O3-MnO2-CdO ternary oxide glasses with amorphous properties were synthesised using the melt-quenching method. Structural and physical property analyses showed that the amount of non-bridging oxygen and the system stiffness increases, and the oxide network filling is more tightly packed as cadmium oxide (CdO) gradually replaces manganese Oxide (MnO2) in the glass. The radiation-shielding performance of the B2O3-MnO2-CdO glasses was evaluated using the shielding parameters calculated by the MCNPX simulation and the Phy-X program. Glasses with 40% and 50% CdO loading exhibited an average specific lead equivalent (PbE) of 0.241 and 0.294 mmPb/mm in the medical X-ray diagnostic area at 0.03–0.08 MeV; thus, they could fully meet the specific PbE requirements for application as "protection devices against diagnostic medical X-radiation". Furthermore, their photon attenuation capability is superior to that of various commercial shielding glasses in fast-neutron nuclear applications at 1°–103 MeV. In addition, compared to the borate glass systems studied in the literature, B2O3-MnO2-CdO glasses have fast neutron removal cross-sections of 0.125 cm−1 at a smaller density of 3.9043–4.8135 g/cm3, making them potentially excellent fast neutron absorbers.  相似文献   

3.
《Ceramics International》2020,46(10):16452-16458
This paper focuses on the effect of Bi2O3 content (up to 80 mol%) on mechanical features and radiation shielding characteristics of boro-tellurite glasses within TeO2–B2O3–Bi2O3 system. The basic mechanical parameters such as oxygen molar volume, packing density, hardness, and elastic moduli were studied based on Makishima–Mackenzie's theory. The shielding studies of the TeO2–B2O3–Bi2O3 glasses included gamma, electron and neutron radiations. The newly developed Phy-X/PSD program and Geant4 simulation were used to calculate the shielding parameters such as mass attenuation coefficient (μ/ρ), tenth value layer (TVL), mean free path (MFP), stopping power (ψe)), removal cross section (RCS), CSDA range, effective atomic number (Zeff), and half value layer (HVL). The concentration of Bi2O3 content had a significant effect on the gamma shielding competence of the investigated glasses. Form the results of gamma shielding studies, the highest μ/ρ (99.845 cm2/g) occurred at 0.015 MeV for TBB80 and the lowest μ/ρ (0.039 m2/g) occurred at 4 MeV for TBB40. The maximum values of Zeff for gamma interaction occurred at 0.02 MeV and they were 77.26, 78.81, 79.94, 80.80, and 81.48 for TBB40, TBB50, TBB50, TBB60, TBB70, and TBB80, respectively. The gamma shielding features of the investigated glasses were compared with those of various ordinary concretes, and Pb-free, Pb-based, and commercial glasses. The Bi2O3 content had also a considerable influence on the electron shielding competence of the tested glasses. The maximum values of Zeff for electron interaction occurred at 14 MeV and they were 44.58, 47.72, 50.41, 52.75, and 53.73 for TBB40, TBB50, TBB50, TBB60, TBB70, and TBB80, respectively. The results revealed that the bismuth boro-tellurite glasses could be useful for the shielding against gamma, electron, and neutron radiations, wherein the Bi2O3 content can be balanced according to the type and energy of radiation.  相似文献   

4.
To observe direct effect of samarium (III) oxide reinforcement on physical, thermal, optical, structural and nuclear radiation attenuation properties, a broad-range experimental and numerical investigations were performed with a group of novel borotellurite glasses. FTIR spectra of powdered samples were taken at 250-4000 cm-1. The transmittance and absorption characteristics, optical band gaps, and Urbach energies were measured. The glass transition temperatures, crystallization temperatures and melting temperature values of the samples were determined. Nuclear radiation shielding properties have been determined for gamma-ray, neutrons and heavy charged particles. The lowest transmittance and highest absorbance were reported for the TBVS1.5 sample with highest Sm2O3 additive. In addition, obtained results from the nuclear radiation shielding calculations have showed that TBVS1.5 sample has superior nuclear radiation shielding properties against gamma-ray, neutron and heavy charged particles. The increasing Sm2O3 additive has visibly improved the nuclear radiation attenuation properties by keeping other material properties within usable limits.  相似文献   

5.
The impact of rare-earth oxide (La2O3) on the structural, mechanical and optical properties of cobalt-doped heavy metal borate glassy system is studied. XRD assured the amorphous nature of the prepared samples. The density and average boron-boron separation were found to increase with La2O3 content, thereby enforcing the compactness of the glass network. FT-IR analysis revealed the growth of NBO's ratio due to the gradual conversion of the tetrahedral (BO4) to trigonal (BO3) units with the development of a certain boroxol group (B3O6) fraction. A noticeable enhancement of the elasticity properties, such as the elastic, bulk, and Young's moduli, as well as the microhardness, was confirmed by measuring the ultrasound velocities within prepared samples. The absorption and photoluminescence emission spectra showed a progressive enhancement of Co3+/Co2+ ions in the tetrahedral and/or octahedral positions with La2O3 content. The ligand field strength and Racah parameters were estimated, in which the ionicity nature between Co2+ ions and the nearby ligands is inferred from the nephelauxetic effect. Absorption edge analysis, here performed through Tauc's model, showed a decrease in the band gap and a rise in Urbach energy; the values of each, together with the metallization parameter, reflect the semiconducting character of the prepared samples. The dispersion of the refractive index was determined using the Wemple-DiDomenico single oscillator model and compared to the optical gap energy. Additionally, the nonlinear optical coefficients, here determined within the lower energy spectral range using a third-order nonlinear susceptibility, exhibited progressively increasing value, suggesting a possible integration of the current system in potential nonlinear optical applications. Furthermore, the absorption and photoluminescence spectral tunability here offered through La2O3 additives qualifies the current glasses as optically active materials for many possible applications in multifunctional optical devices operating in visible and near-infrared spectral regimes.  相似文献   

6.
This study is focused on investigating the role of bismuth oxide (Bi2O3) nanoparticles to improve structural, optical, electrical, and mechanical properties of low-density polyethylene (LDPE). For this purpose, Bi2O3 nanoparticles were synthesized by using the solvothermal method and examined by transmission electron microscopes (TEM), x-ray diffraction (XRD), Fourier transformed infrared (FTIR) spectroscopy, and ultraviolet–visible (UV–Vis) light absorption methods. LDPE-based nanocomposites were prepared by changing the nanoparticle additive ratio in the composite from 0% to 2% by weight. The composites were analyzed in the context of their FTIR spectra, atomic force microscope (AFM) images, UV–Vis light absorption spectra, stress–strain curves, and energy storage abilities. While the AFM findings indicate a smoother surface for the composites, the optical band gap analysis reveals a slightly decreased direct optical band gap energy. The analyses based on dielectric spectroscopy also highlight the LDPE/0.5% n-Bi2O3 composite in terms of the best energy storage capability. Additionally, the highest Young's modulus, toughness, stress at break, and percentage of strain at break were also recorded for the LDPE/0.5% n-Bi2O3 composite. In this context, the LDPE/0.5% n-Bi2O3 composite with improved dielectric and mechanical properties can be suggested as a new promising LDPE-based nanocomposite with better properties for industrial purposes.  相似文献   

7.
Herein, a traditional melt quenching method was utilized to synthesize glasses with a nominal chemical composition (80-x)TeO2-xB2O3–5ZnO–5Li2O3–10Bi2O3: 30≤ x ≤ 80 mol%). The produced sample was coded as TBBZL30 to TBBZL80. X-ray diffraction (XRD) has been employed to test the amorphous nature of the synthesized samples. In the range of 200–500 nm wavelength, UV–Vis spectra for the glasses have been performed. Optical energy gaps (Egap) have been determined based on the absorption measurements. With the help of (Egap), refractive index (n), molar polarizability (αM), metallization criterion (MCri.), molar refractivity (RM), static dielectric constant (εSta.), optical dielectric constant (εOpt.), reflection loss (RL) and optical transmission (TOpt.) have been calculated. For the fabricated boro-tellurite glasses, Phy-X/PSD was used to report some shielding factors for several energies between 15 keV and 15 MeV. The maximum attenuation for all samples took place at 15 keV and the mass attenuation coefficient varied between 52.309 and 57.084 cm2/g. The linear attenuation coefficient (LAC) results demonstrated that TBBZL80 has the highest attenuation than the rest of samples which is due to high content of TeO2 (containing 80 mol% of TeO2) whereas TBBZL30 has the lowest attenuation. The LAC for the fabricated samples varied between 230.160 and 351.064 cm-1 at 15 keV. The minimum effective atomic number (EAN) occurred between 0.8 and 4 MeV and varied between 15.16 and 17.35 for TBBZL30 and 25.10–28.33 for TBBZL80. The addition of TeO2 was found to enhance the EAN and improved shielding properties for the tested TBBZL glass systems.  相似文献   

8.
Glasses in the 30La2O3-40TiO2-30Nb2O5 system are known to have excellent optical properties such as refractive indices over 2.25 and wide transmittance within the visible to mid-infrared (MIR) region. However, titanoniobate glasses also tend to crystallize easily, significantly limiting their applications in optical glasses due to processing challenges. Therefore, the 30La2O3-40TiO2-(30−x) Nb2O5-xAl2O3 (LTNA) glass system was successfully synthesized using a aerodynamic containerless technique, which improves glass thermal stability and expands the glass-forming region. The effects of Al2O3 on the structure, thermal, and optical properties of base composition glasses were investigated by XRD, DSC, NMR, Raman spectroscopy, and optical measurements. DSC results indicated that as the content of Al2O3 increased, the thermal stability of the glasses and glass-forming ability increased, as the 30La2O3-40TiO2-25Nb2O5-5Al2O3 (Nb-Al-5) glass obtained the highest ΔT value (103.5°C). Structural analysis indicates that the proportion of [AlO4] units increases gradually and participates in the glass network structure to increase connectivity, promoting more oxygen to become bridging oxygen and form [AlO4] tetrahedral linkages to [TiO5] and [NbO6] groups. The refractive index values of amorphous glasses remained above 2.1 upon Al2O3 substitution, and a transmittance exceeding 65% in the visible and mid-infrared range. The crystallization activation energies of 30La2O3-40TiO2-30Nb2O5 (Nb-Al-0) and Nb-Al-5 glasses were calculated to be 611.7 and 561.4 kJ/mol, and the Avrami parameters are 5.28 and 4.96, respectively. These results are useful to design new optical glass with good thermal stability, high refractive index and low wavelength dispersion for optical applications such as lenses, endoscopes, mini size lasers, and optical couplers.  相似文献   

9.
10.
In this study, a series of Bi2O3 reinforced bariumtelluroborate (TBX) glasses with the nominal composition 20TeO2 + (50-x)B2O3 + 29.5BaO + xBi2O3 + 0.5Er2O3 (where x=0,5,10,15 and 20 in wt%) were manufactured using traditional melt-quenching method. The structural and compositional studies were performed by using XRD and FTIR spectra. In general, the glass matrix consists of the trigonal-planar and tetrahedral units of borates, tellurate and tellurite groups of tellurites, and the non-bridging oxygen (nBO). In addition to that, BiO3 and BiO6 groups are present in top-order glasses. The gamma-ray shielding (γ-RS) ability was evaluated through the vital parameters like the mass-attenuation coefficient (MAC), mean free-path (MFP), half-value layer (HVL), and effective atomic-number (Zeff). TB20 glass is happened to be the best candidate by giving the highest value for MAC and the lowest MFP and HVL, owing to its large density, 6.922 g/cm3. The fast neutron-removal cross-section (∑R) is assessed to investigate the neutron shielding capacity of TBX glasses. The γ-rays shielding properties of TBX glasses were observed better than some ordinary shields such as barite-concrete and commercial shielding glasses developed by SCHOTT Company.  相似文献   

11.
《Ceramics International》2020,46(15):23357-23368
Impacts of lead and bismuth oxides insertion on a novel glass system of P2O5, B2O3, Li2O, Al2O3 according the formula 25B2O3–25P2O5–10Li2O–5Al2O3–5ZnO-xPbO+ (30-x)Bi2O3, x = 5,10, 15, 20, 25 mol%. The mass attenuation coefficient (μm = μ/ρ) simulated between 0.015 and 15 MeV using MCNP and calculated theoretically using Phy-X/PSD program. Based on the simulated μm, other significant parameters such as linear attenuation coefficient (LAC), half and tenth value layer (HVL, TVL), mean free path (MFP), and effective atomic number (Zeff) were calculated for fabricated glasses. The G-P fitting methods were used to calculate the exposure and energy absorption buildup factors (EBF and EABF) for fabricated glasses. Furthermore, fast neutron removal cross sections (ΣR) were calculated theoretically for fabricated glasses. The prepared glasses were effective shielding material which can reduce fast neutrons as well as gamma rays.  相似文献   

12.
《Ceramics International》2022,48(9):12829-12837
A melt quenching method was applied to fabricate a series of bismuth lithium borate glasses with a chemical composition of 65(B2O5) + 20(Bi2O3) + (15 ? x)(Li2O) + x(Nd2O3), where x = 0, 1, 2, 3, and 4 mol%. The structural changes in the fabricate glasses were studied via the Fourier transform infrared spectroscopy (FT-IR). The FT-IR spectra of the manufactured glasses indicated the transformation of the structural unit BO4. The mechanical properties of the produced glasses were evaluated via the ultrasonic measurement (longitudinal and shear velocities) and the Makishima–Mackenzie modulus calculations. Furthermore, the role of Nd2O3 in improving mechanical properties was studied theoretically and experimentally and results showed that ultrasonic velocities and elastic moduli decreased with increasing the Nd2O3 content. The Young's modulus decreased from 68.47 to 50.61 GPa as the Nd2O3 content increased from 0 to 4 mol%, respectively. The gamma ray shielding properties of the studied glass samples were evaluated using the Monte Carlo simulations between 0.223 and 2.506 MeV. The simulated data showed that the fabricated glass without Nd2O3 has the highest linear attenuation coefficient, which varied between 0.210 and 0.212 cm?1 for photons with energies ranging from 0.2234 to 2.506 MeV.  相似文献   

13.
《Ceramics International》2020,46(13):21120-21127
Radiation is used in a variety of different fields, and thus protection from its hazardous effects become a popular subject for researchers. For this purpose, in the present study, waste soda-lime-silica glasses as SiO2–Na2O–CaO–Bi2O3 and SiO2–Na2O–CaO–Sb2O3 were investigated for X-rays photon characteristics in the energies of 0.01–0.1 MeV via WinXCom program, and the results were compared with the experimental findings obtained at 0.04 MeV. Waste packaging glass was evaluated by adding varying amounts (0.005, 0.05, and 0.5 percentages) of Bi2O3 and Sb2O3. Seven different glass batches were prepared by following the procedures of precisely weighing the relevant amounts to obtain 10 g specimen in total, homogeneously mixing the respective contents, and thoroughly melting in an Au–Pt crucible via conventional electrical furnace at 1250 °C for 4 h. The linear attenuation coefficient (LAC) for glass specimens were experienced at 0.04 MeV, and it was found out that increasing contents of both oxides increased the LAC implying that a decrease in X-ray transmission occurred. From the point of WinXCom calculations, the LAC and mass attenuation coefficient (MAC) increased while half value layer (HVL) and mean free path (MFP) thicknesses decreased as the oxide substances increased in the glass specimens. That is, Sb2O3 addition provided higher X-rays attenuation characteristics in comparison to Bi2O3 additive. Further, the experimental data at 0.04 MeV were compared with WinXCom calculations, and it was figured out that the data were parallel for each other, but the correlation coefficient (R2) was found as 0.15 which means that the values were in loose agreement.  相似文献   

14.
《Ceramics International》2022,48(2):2124-2137
In a bid to expand the amount of information available on glass systems and their potential applications for radiation shielding design, glass samples with the compositions (30-x)SrO-xAl2O3–68B2O3–2V2O5(x = 5, 7.5, 10, 12.5&15 mol %) coded as SABV0 - 4 were prepared by the melt-quenching technique and analyzed for their optical, structural, physical, and radiation shielding features. The glassy (amorphous) nature of the SABV glass samples was affirmed by broad peaks of X-ray diffraction spectra. Calculated values of density and molar volume shown opposite behavior and the variation of these values were discussed as structural modifications in the glass matrix. From recorded optical absorption spectra optical band gap energy (Eg)-indirect transition, Urbach energy and optical basicity were estimated. FTIR spectra were recorded for all the samples in the range 400 cm?1 to 4000 cm?1. The FTIR absorbance spectra unveiled the SABV network structure mainly incorporating of BO3 and BO4 units. Raman spectroscopy is achieved to detect the structural changes and at higher wavenumber, B–O stretching modes in [BO3] observed with one or two NBO's. The results of ESR spectra of glasses have indicated the highly covalent environment of vanadium ions. Analysis of the photon shielding parameters of the glasses which were obtained primarily from FLUKA Monte Carlo simulations and XCOM computations revealed photon energy and glass chemical composition dependence. The mass attenuation coefficient and effective atomic number ranged from 0.2668 to 0.3385 cm2g-1 and 12.98–15.93 accordingly as the weight fraction of Sr increased from 16.06 to 26.72% in the glasses. Generally, photon shielding ability of the SABV glasses follows the trend: SABV0 > SABV1 > SABV2 > SABV3 > SABV4. The thermal neutron total cross section follows the same trend with values fluctuating between 71.9553 and 80.6268 cm?1. However, SABV1 showed superior fast neutron moderating capacity among the glasses. The present SABV glasses showed outstanding photon shielding ability compared to common shields. The prepared glasses are thus suitable candidates for radiation protection applications.  相似文献   

15.
16.
In this work, the effect of gradual addition of Al2O3 substituting SiO2 on the structural, thermal, and mechanical properties of SiO2–BaF2–K2O–GdF3–Sb2O3‐based oxyfluoride glasses have been studied. The X‐ray diffraction (XRD) patterns and differential scanning calorimetric (DSC) curves indicate that there is a distinct primary crystallization corresponding to BaGdF5 phase formation in the samples without (0AlG) and with 5 mol% substitution of Al2O3 (5AlG) while the sample with 10 mol% of Al2O3 (10AlG) does not show such crystallization event. Further, the activation energy (Ea) for fluoride crystal formation is higher for the 5AlG in comparison to the 0AlG glass as determined by Kissinger, Augis‐Bennett and Ozawa models. Fourier transform infrared (FTIR) and Raman spectroscopy analysis confirmed the structural modification with the gradual addition of Al2O3 in the glass matrix revealing dominant presence of AlO4 tetrahedral units in 10AlG sample unlike in 5AlG sample which exhibited the manifestation of AlO6 units. Such structural variation has further been substantiated from the estimated elastic properties like Young's modulus (E), shear modulus (G), bulk modulus (K), longitudinal modulus (L), and mean ultrasonic velocity (Um) by showing a decrease for 5AlG sample in comparison with 0AlG sample followed by subsequent increase for 10AlG sample.  相似文献   

17.
Engineering borate glass structure by simple compositional modification is essential to meet the particular demands from both industrial and photonic research communities. In this article, we demonstrate how the mixing of Li2O with Na2O, K2O, or Cs2O influences the relative abundance of 3- and 4-coordinated borons in the glass network, as exhibited by nuclear magnetic resonance (NMR) and Raman spectra. A systematic study is given of the alkali mixing effect on the glass properties including: glass transition temperature, microhardness, density, refractive index, and particularly the near-infrared photoluminescence properties (eg, bandwidth and lifetime) of Er3+ which has been barely studied in mixed alkali borate glasses. It is interesting to note that the glass transition temperature, refractive index and emission lifetime of Er3+ manifest mixed alkali effect, in sharp contrast with microhardness, density, and emission bandwidth which vary monotonically upon the alkali mixing. The possible causes for the differences are discussed in the light of the compositional dependence of boron species and nonbridging oxygen upon alkali mixing.  相似文献   

18.
彭兵兵  宦克为  肖楠  尹笑乾  杨继凯 《精细化工》2021,38(11):2299-2304,2311
以导电玻璃为基底采用水热法制备了WO3纳米片薄膜,再通过溶剂热法改变不同溶剂热反应时间(6、8和10 h)在WO3纳米片薄膜上生长Bi2WO6制备了WO3/Bi2WO6复合薄膜.利用XRD、SEM、UV-Vis、光电流、光电催化和交流阻抗对WO3/Bi2WO6复合薄膜的结构和光电性能进行表征与测定.结果表明,WO3纳米片薄膜的光电流密度为0.74 mA/cm2,对质量浓度为6.0 mg/L亚甲基蓝的光电催化效率为47.9%.不同WO3/Bi2WO6复合薄膜的光电化学性能均优于单一WO3纳米薄膜,且溶剂热反应时间为8 h的WO3/Bi2WO6复合薄膜具有最高的光电流密度(1.22 mA/cm2)和最优的光电催化效率(58.6%).WO3/Bi2WO6复合薄膜有效降低了复合薄膜内部电子阻抗,增加了有效光电化学反应位点,显著提升了光电化学性能.  相似文献   

19.
《Ceramics International》2017,43(14):11305-11311
The unconventional Heavy Metal Oxide Glasses (HMOG) are characterized by a low phonon energy, large infrared range transmission, high refractive index and nonlinear optical properties. Ternary glasses have been synthesized and studied in the Sb2O3– MoO3-ZnCl2 system. Further, the glass formation compositional limits are reported and some glass samples with the formula: (90-x)Sb2O3 -xMoO3–10 ZnCl2 (10 ≤ x ≤ 50, mole%) were elaborated. Thermal properties have been measured and indicating that the glass transition temperature decreases with increasing proportions of molybdenum oxide. The evolution of density, microhardness and elastic modulus has been studied as functions of parameter x and Raman spectra measurements have been shown the partial conversion of MoO6 octahedral units into MoO4 tetrahedral.  相似文献   

20.
La2O3–Ga2O3M2O5 (M = Nb or Ta) ternary glasses were fabricated using an aerodynamic levitation technique, and their glass‐forming regions and thermal and optical properties were investigated. Incorporation of adequate amounts of Nb2O5 and Ta2O5 drastically improved the thermal stabilities of the glasses against crystallization. Optical transmittance measurements revealed that all the glasses were transparent over a wide wavelength range from the ultraviolet to the mid‐infrared. The refractive indices of the glasses increased and the Abbe number decreased upon substituting Ga2O3 with Nb2O5, and the decrease in the Abbe number was significantly suppressed when Ta2O5 was incorporated into the glass. As a result, excellent compatibility between high refractive index and lower wavelength dispersion was realized in La2O3–Ga2O3–Ta2O5 glasses. Analysis based on the single‐oscillator Drude–Voigt model provided more systematical information and revealed that this compatibility was due to an increase in the electron density of the glass.  相似文献   

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