Using a melt-cooling process with the host glass,Dy_(2)O_(3)(1 wt%,2 wt%,3 wt%,and 4 wt%) doped tellurite glasses were produced.A(65-x)TeO_(2)-20B_(2)O_(3)-10Al_(2)O_(3)-SGeO_(2)-xDy_(2)O_(3) glass system was analyzed...Using a melt-cooling process with the host glass,Dy_(2)O_(3)(1 wt%,2 wt%,3 wt%,and 4 wt%) doped tellurite glasses were produced.A(65-x)TeO_(2)-20B_(2)O_(3)-10Al_(2)O_(3)-SGeO_(2)-xDy_(2)O_(3) glass system was analyzed by Xray diffraction.The patterns have a hump at 2θ=27°-29° and no sharp peaks,indicating that all the glass samples are amorphous.The Vickers microhardness determines how resistant a glass is to persistent deformation produced by a harder substance.Differential scanning calorimetry(DSC) at 300-550℃ was used to evaluate the thermal properties of the Dy_x glass samples.The glass transition temperature T_g(small endothermic peak),start crystallization temperature T_x and crystallization temperature T_c can all be seen on the DSC thermogram(exothermic peaks).The UV-Vis transmittance and absorption spectra were measured.The optical data show that the values of E_d^(ir),E_g^(Ind) and E_U decrease as the amount of Dy_(2)O_(3)increases,indicating a narrowing of the tails due to localized states in the forbidden gap.A concentration quenching event occurs when Dy^(3+) concentrations are above a certain threshold(1%).The addition of Dy_(2)O_(3) increases glass density,while the addition of other Dy(Ⅲ) oxides increases sample density.The radiation shielding values change as a consequence of density fluctuation.The sample with the highest amount of Dy_(2)O_(3)(Dy_(4)) has stronger radiation shielding characteristics;hence,it is superior in terms of shielding outcomes at all energy levels.Such Dy_x samples can be used in various forms of ionizing radiation shielding.展开更多
This research aims to study the impact of yttrium oxide on the radiation protection features of polyvinyl alcohol(PVA) for gamma shielding applications.The yttrium oxide(Y_(2)O_(3)) was instilled through the PVA matri...This research aims to study the impact of yttrium oxide on the radiation protection features of polyvinyl alcohol(PVA) for gamma shielding applications.The yttrium oxide(Y_(2)O_(3)) was instilled through the PVA matrix by different contents(x=0.1 wt%,0,3 wt%,0,7 wt%,0,9 wt%),The morphology of the prepared PVA/Y_(2)O_(3)composites was characterized using scanning electron microscopy(SEM).The samples were investigated using absorption edge,transmittance spectra and dielectric properties.The transmittance and the bandgap energy decrease as the Y2O3content increases while there is an increase in ε’ and ε" as well as the ac conductivity with the content increment of Y_(2)O_(3)till 0.7 wt%.The te mperature dependence of the dc conductivity was measured for all samples in the range of 260-460 K,and it increases with the temperature increasing.To correlate the electrical characteristics of the PVA/Y_(2)O_(3)composites with their structure and evaluate electrical properties with the help of equivalent circuit matching with the experimentally electrical response in the impedance spectrum,the radiation protection properties were also investigated to get the radiation shielding performance of these PVA/Y_(2)O_(3)composite films with varying Y_(2)O(3)content.The linear attenuation coefficient(μ),half value layer(T_(0.5)),and mass attenuation coefficient(μm) were measured.According to all obtained data,PVA/Y_(2)O_(3)composite films with various percentages(0.1 wt%,0.3 wt%,0.7 wt%,0.9 wt%) can be used as a radiation shielding material.展开更多
Background In recent years,the preparation of transparent glass in the visible region has led to the development of radiation shielding materials with measuring structure and optical properties.Also,the study on the i...Background In recent years,the preparation of transparent glass in the visible region has led to the development of radiation shielding materials with measuring structure and optical properties.Also,the study on the interaction of neutron radiation with matter is important in the field of radiation protection.Purpose Preparation of transparent calcium and bismuth borate oxide glasses containing Nb^(5+)ions can be used as a neutron radiation shield and determine refractive index with different methods for this glass.Methods Niobium bismuth borate glasses with composition 60B_(2)O_(3)–20CaO–(20−x)Bi_(2)O_(3)–xNb_(2)O_(5),where(x is in mol%,0≤x≤10),have been prepared using conventional melt-quenching technique;the structure of each sample was studied by XRD,FTIR,and UV spectra chart analysis.Results XRD and FTIR showed that all glass samples were highly homogeneous and had structured with short-rangeorder/amorphous solids.The refractive index of each sample was estimated by charts of UV–Vis and FTIR,in addition to an empirical method,and we obtained values very close to each other.The refractive index values are relatively high,so this glass can be used in nonlinear studies as well as luminescence characterization.The macroscopic fast neutron removal cross sections(R/ρ)have calculated,for all samples,and the highest value was in sample containing 2.5%niobium pentoxide.Conclusion Bismuth borate glass containing a few niobium pentoxide can be used as a protective shield of neutrons.展开更多
Background Radiation protection and detection have been a main interest for researchers.The prepared glass samples were subjected to experimental investigations to evaluate their mechanical and attenuation properties....Background Radiation protection and detection have been a main interest for researchers.The prepared glass samples were subjected to experimental investigations to evaluate their mechanical and attenuation properties.As a consequence,the values of the mass attenuation coefficient,total electronic cross section,the effective atomic number and an effective electron number were determined and utilized to assess the shielding effectiveness of the investigated glass samples.The mass attenuation coefficients of these samples were calculated theoretically using WinXcom program.Purpose Preparation of glass of borate with zinc and barium can withstand shock,heat and corrosion to be used as a radiation shield.Methods Glass samples were prepared by melt quenching technique.Density and molar volume measurements were obtained by applying the Archimedes principle.The hardness was measured by using a microhardness tester(Leco AMH 100,USA)for sample indentation.The thermal behavior of the glass samples was investigated by differential scanning calorimetry(DSC).Also,by using a scintillator detector(1.5″×1.5″NaI(Tl))exposed to ^(232)Th,^(137)Cs and ^(60)Co gamma ray sources with accuracy range 0.12%.Results The investigated glasses have relatively good gamma ray attenuation properties,water resistance ability and thermal stability with increasing barium oxide.So,they can be used in containers for keeping radioactive waste and radioactive sources.Conclusion The changes in the molar volume and density show approximately opposite linear trends.Also,μm is dependent on the chemical compositions of glass samples and energy of gamma rays.Good agreement between the experimentally obtained mass attenuation coefficient values and the corresponding theoretical predictions based on the known WinXcom program was observed.Additionally,the effect of gamma irradiation on this glass is minor because its impact on the hardness values and dissolution rate is extremely small.展开更多
文摘Using a melt-cooling process with the host glass,Dy_(2)O_(3)(1 wt%,2 wt%,3 wt%,and 4 wt%) doped tellurite glasses were produced.A(65-x)TeO_(2)-20B_(2)O_(3)-10Al_(2)O_(3)-SGeO_(2)-xDy_(2)O_(3) glass system was analyzed by Xray diffraction.The patterns have a hump at 2θ=27°-29° and no sharp peaks,indicating that all the glass samples are amorphous.The Vickers microhardness determines how resistant a glass is to persistent deformation produced by a harder substance.Differential scanning calorimetry(DSC) at 300-550℃ was used to evaluate the thermal properties of the Dy_x glass samples.The glass transition temperature T_g(small endothermic peak),start crystallization temperature T_x and crystallization temperature T_c can all be seen on the DSC thermogram(exothermic peaks).The UV-Vis transmittance and absorption spectra were measured.The optical data show that the values of E_d^(ir),E_g^(Ind) and E_U decrease as the amount of Dy_(2)O_(3)increases,indicating a narrowing of the tails due to localized states in the forbidden gap.A concentration quenching event occurs when Dy^(3+) concentrations are above a certain threshold(1%).The addition of Dy_(2)O_(3) increases glass density,while the addition of other Dy(Ⅲ) oxides increases sample density.The radiation shielding values change as a consequence of density fluctuation.The sample with the highest amount of Dy_(2)O_(3)(Dy_(4)) has stronger radiation shielding characteristics;hence,it is superior in terms of shielding outcomes at all energy levels.Such Dy_x samples can be used in various forms of ionizing radiation shielding.
基金funded by the Deanship of Scientific Research at Princess Nourah bint Abdulrahman University,through the Research Funding Program (FRP-1443-26)。
文摘This research aims to study the impact of yttrium oxide on the radiation protection features of polyvinyl alcohol(PVA) for gamma shielding applications.The yttrium oxide(Y_(2)O_(3)) was instilled through the PVA matrix by different contents(x=0.1 wt%,0,3 wt%,0,7 wt%,0,9 wt%),The morphology of the prepared PVA/Y_(2)O_(3)composites was characterized using scanning electron microscopy(SEM).The samples were investigated using absorption edge,transmittance spectra and dielectric properties.The transmittance and the bandgap energy decrease as the Y2O3content increases while there is an increase in ε’ and ε" as well as the ac conductivity with the content increment of Y_(2)O_(3)till 0.7 wt%.The te mperature dependence of the dc conductivity was measured for all samples in the range of 260-460 K,and it increases with the temperature increasing.To correlate the electrical characteristics of the PVA/Y_(2)O_(3)composites with their structure and evaluate electrical properties with the help of equivalent circuit matching with the experimentally electrical response in the impedance spectrum,the radiation protection properties were also investigated to get the radiation shielding performance of these PVA/Y_(2)O_(3)composite films with varying Y_(2)O(3)content.The linear attenuation coefficient(μ),half value layer(T_(0.5)),and mass attenuation coefficient(μm) were measured.According to all obtained data,PVA/Y_(2)O_(3)composite films with various percentages(0.1 wt%,0.3 wt%,0.7 wt%,0.9 wt%) can be used as a radiation shielding material.
文摘Background In recent years,the preparation of transparent glass in the visible region has led to the development of radiation shielding materials with measuring structure and optical properties.Also,the study on the interaction of neutron radiation with matter is important in the field of radiation protection.Purpose Preparation of transparent calcium and bismuth borate oxide glasses containing Nb^(5+)ions can be used as a neutron radiation shield and determine refractive index with different methods for this glass.Methods Niobium bismuth borate glasses with composition 60B_(2)O_(3)–20CaO–(20−x)Bi_(2)O_(3)–xNb_(2)O_(5),where(x is in mol%,0≤x≤10),have been prepared using conventional melt-quenching technique;the structure of each sample was studied by XRD,FTIR,and UV spectra chart analysis.Results XRD and FTIR showed that all glass samples were highly homogeneous and had structured with short-rangeorder/amorphous solids.The refractive index of each sample was estimated by charts of UV–Vis and FTIR,in addition to an empirical method,and we obtained values very close to each other.The refractive index values are relatively high,so this glass can be used in nonlinear studies as well as luminescence characterization.The macroscopic fast neutron removal cross sections(R/ρ)have calculated,for all samples,and the highest value was in sample containing 2.5%niobium pentoxide.Conclusion Bismuth borate glass containing a few niobium pentoxide can be used as a protective shield of neutrons.
文摘Background Radiation protection and detection have been a main interest for researchers.The prepared glass samples were subjected to experimental investigations to evaluate their mechanical and attenuation properties.As a consequence,the values of the mass attenuation coefficient,total electronic cross section,the effective atomic number and an effective electron number were determined and utilized to assess the shielding effectiveness of the investigated glass samples.The mass attenuation coefficients of these samples were calculated theoretically using WinXcom program.Purpose Preparation of glass of borate with zinc and barium can withstand shock,heat and corrosion to be used as a radiation shield.Methods Glass samples were prepared by melt quenching technique.Density and molar volume measurements were obtained by applying the Archimedes principle.The hardness was measured by using a microhardness tester(Leco AMH 100,USA)for sample indentation.The thermal behavior of the glass samples was investigated by differential scanning calorimetry(DSC).Also,by using a scintillator detector(1.5″×1.5″NaI(Tl))exposed to ^(232)Th,^(137)Cs and ^(60)Co gamma ray sources with accuracy range 0.12%.Results The investigated glasses have relatively good gamma ray attenuation properties,water resistance ability and thermal stability with increasing barium oxide.So,they can be used in containers for keeping radioactive waste and radioactive sources.Conclusion The changes in the molar volume and density show approximately opposite linear trends.Also,μm is dependent on the chemical compositions of glass samples and energy of gamma rays.Good agreement between the experimentally obtained mass attenuation coefficient values and the corresponding theoretical predictions based on the known WinXcom program was observed.Additionally,the effect of gamma irradiation on this glass is minor because its impact on the hardness values and dissolution rate is extremely small.
