Three alkaline earth silicate phosphors: Sr2MgSi2O7∶Eu, Dy, Gd, Sr3MgSi2O8∶Eu, Dy, Gd and Sr2MgSi2O7∶Eu, Dy were prepared and their luminescent properties were investigated. The Photoluminescence (PL) measurements ...Three alkaline earth silicate phosphors: Sr2MgSi2O7∶Eu, Dy, Gd, Sr3MgSi2O8∶Eu, Dy, Gd and Sr2MgSi2O7∶Eu, Dy were prepared and their luminescent properties were investigated. The Photoluminescence (PL) measurements indicated that the phosphors gave a longer emitting phosphorescence phenomenon by comparing with those without Gd2O3 activator, in which a better afterglow characteristic was observed by adding Gd2O3 to the phosphors. While little influence on the structure of luminescent materials was observed via XRD spectra, and obvious emission wavelength shift was exhibited due to the differences in the structure parameters of the two hosts. The results revealed that the improvement was due to nonequivalent substitution to produce more e-traps, and energy transfer from Gd3+ to Dy3+, to boost the performance of Sr2MgSi2O7∶Eu, Dy phosphor. Role of Gd3+ co-doped into Sr2MgSi2O7∶Eu, Dy matrix and the possible long-lasting phosphorescence progress were discussed.展开更多
In this study,we fabricated poly(3-hydroxybutyrate-3-hydroxyvalerate)(PHBV)coatings doped with Gd^(3+)(1,5,and 10×10^(−4) mol/L)on Ti6Al4V alloy for the first time to promote soft tissue sealing around dental imp...In this study,we fabricated poly(3-hydroxybutyrate-3-hydroxyvalerate)(PHBV)coatings doped with Gd^(3+)(1,5,and 10×10^(−4) mol/L)on Ti6Al4V alloy for the first time to promote soft tissue sealing around dental implants.The corrosion resistance of Gd^(3+)-modified PHBV-coated Ti6Al4V was studied by electrochemical and immersion tests,respectively,whereas CCK-8 and RT-PCR evaluated the biocompatibility to human gingival fibroblasts(HGFs)and human umbilical vein endothelial cells(HUVECs).It was found that the Gd^(3+)-modified PHBV coating could enhance the corrosion resistance of Ti6Al4V.In vitro cell tests showed that PHBV coatings with and without Gd^(3+) addition could promote adhesion and proliferation of HGFs and HUVECs,showing a Gd^(3+) content-dependent manner.Moreover,it was found that the PDA-PHBV@1Gd showed the best proliferation to HGFs by up-regulating gene expressions of VINCULIN,ITGB1,and ITGA3,whereas the best response to HUVECs with the highest gene expression of eNOS and HIF-1αgenes was found in the PDA-PHBV@5Gd-coated group.展开更多
In this study,Gd^(3+)and Bi^(3+)ions act to redshift the emission band to orange region,and to enhance significantly the maximum emission of YAG:Ce^(3+).On account that size mismatch between the host and the doped Gd^...In this study,Gd^(3+)and Bi^(3+)ions act to redshift the emission band to orange region,and to enhance significantly the maximum emission of YAG:Ce^(3+).On account that size mismatch between the host and the doped Gd^(3+)ion,the crystal structure turns soft,and the emission spectra are not tuned from 540 to 570 nm but decreased the emission intensity.Accordingly,an effective way to increase emission intensity is to introduce Bi^(3+)ion into the YAG:Ce^(3+),Gd^(3+)phosphors.Experimental results show partial overlapping between the emission band of Bi^(3+)ion and the excitation band of Ce^(3+)ion,indicating that the energy transfer from Bi^(3+)to Ce^(3+)ions exists in the(Y_(1.94)Ce_(0.06)Gd)Al_(5)O_(12):Bi^(3+)phosphor.Bi^(3+)ion can serve as the activator to provide energy for Ce^(3+)ion via cross relaxation phenomenon.Therefore,the(Y_(1.94)Ce_(0.06)Gd)Al_(5)O_(12):Bi^(3+)phosphor could have potential applications in warm white LEDs.展开更多
γ-globulin is a globulin which possesses immune special characteristic. Steven et al. investigated the binding of Gd<sup>3+</sup> to non-immune rabbit immunoglobulin G and its fragments by measurements of...γ-globulin is a globulin which possesses immune special characteristic. Steven et al. investigated the binding of Gd<sup>3+</sup> to non-immune rabbit immunoglobulin G and its fragments by measurements of the enhancement of the solvent-water展开更多
In this study, a series of Gd^(3+)-doped mixed Ni-Cu-Zn ferrites with composition of Zn_(0.5)Ni_(0.3)Cu_(0.2)Fe_(2-x)Gd_(x)O_(4)(x = 0, 0.025, 0.05, 0.075, 0.1) was prepared using self-ignition sol-gel method. The pre...In this study, a series of Gd^(3+)-doped mixed Ni-Cu-Zn ferrites with composition of Zn_(0.5)Ni_(0.3)Cu_(0.2)Fe_(2-x)Gd_(x)O_(4)(x = 0, 0.025, 0.05, 0.075, 0.1) was prepared using self-ignition sol-gel method. The prepared nanoparticles with an average size ranging from 22 to 26 nm show a single-phase cubic structure belonging to the spinel matrix. A rise in the Gd^(3+)concentration leads to an increase in crystallite size and lattice parameter. In Fourier transform infrared spectra, two main absorption bands belonging to the spinel structure are observed. The high-frequency bands(v_(1)) represent the tetrahedral complex, while the lowfrequency bands(v_(2)) signify the octahedral complex. The optical bandgap of the nanoferrites is found within the range of 2.91 to 2.41 eV, depending on their size. The magnetic characteristics of the material,such as saturation magnetization and coercivity are significantly altered with the concentration of Gd^(3+)in the solution. Using Rhodamine B(RhB) as a model organic pollutant, an in-depth investigation of the photocatalytic activity of the compounds was carried out. The present outcomes show that adding an adequate amount of Gd^(3+)significantly enhances the number of hydroxyl radicals produced by the ferrite,in turn, increasing the photocatalytic activity of the material. Mechanism elucidated by scavenger studies reveals that ·OH and holes are the primary reactive radicals responsible for the degradation process.Prepared photocatalysts show an insignificant performance loss in five consecutive cycles. Thus, it is concluded that these photocatalysts are highly suitable for the remediation of dye-contaminated wastewater.展开更多
Cubic phase Tm^(3+)/Yb^(3+):Y_(2)O_(3) and Tm^(3+)/Yb^(3+)/Gd^(3+):Y_(2)O_(3) phosphors were prepared by low temperature combustion technique for upconversion emission in UV-visible range.The 980 nm excitation has gen...Cubic phase Tm^(3+)/Yb^(3+):Y_(2)O_(3) and Tm^(3+)/Yb^(3+)/Gd^(3+):Y_(2)O_(3) phosphors were prepared by low temperature combustion technique for upconversion emission in UV-visible range.The 980 nm excitation has generated UV emission at 314 nm in tridoped phosphor due to the energy transfer from Tm^(3+) to Gd^(3+)ion.Characteristic emission bands from Tm^(3+) are also observed in both the phosphors.Thermally coupled Stark sublevels ^(1)G_(4(a))(476 nm) and ^(1)G_(4(b))(488 nm) of Tm^(3+) ion were utilised for optical thermometry using fluorescent intensity ratio(FIR) method.The result shows that maximum absolute sensitivity in tridoped phosphor is observed to be 1.33 × 10^(-3) K^(-1) at 298 K.Moreover,temperature rise of phosphor at various pump power densities was also measured and it is estimated to achieve 407 K at the pump power density of 38.46 W/cm^(2).展开更多
基金the National Natural Science Foundation (20376009)the Liaoning Natural Science Foundation(20032129) of China
文摘Three alkaline earth silicate phosphors: Sr2MgSi2O7∶Eu, Dy, Gd, Sr3MgSi2O8∶Eu, Dy, Gd and Sr2MgSi2O7∶Eu, Dy were prepared and their luminescent properties were investigated. The Photoluminescence (PL) measurements indicated that the phosphors gave a longer emitting phosphorescence phenomenon by comparing with those without Gd2O3 activator, in which a better afterglow characteristic was observed by adding Gd2O3 to the phosphors. While little influence on the structure of luminescent materials was observed via XRD spectra, and obvious emission wavelength shift was exhibited due to the differences in the structure parameters of the two hosts. The results revealed that the improvement was due to nonequivalent substitution to produce more e-traps, and energy transfer from Gd3+ to Dy3+, to boost the performance of Sr2MgSi2O7∶Eu, Dy phosphor. Role of Gd3+ co-doped into Sr2MgSi2O7∶Eu, Dy matrix and the possible long-lasting phosphorescence progress were discussed.
基金financially supported by the National Natural Science Foundation of China(No.51801198)the Funds of Scientific and Technological Plan of Fujian Province(No.2020Y0083)+3 种基金the National Key Technologies Research and Development Program of China(2016YFC1100502)the Joint Funds of Scientific and Technological Innovation Program of Fujian Province(No.2017Y9059)the Natural Science Foundation of Fujian Province(No.201910027)the Funds of Scientific and Technological Plan of Fujian Province(No.2020L3026)。
文摘In this study,we fabricated poly(3-hydroxybutyrate-3-hydroxyvalerate)(PHBV)coatings doped with Gd^(3+)(1,5,and 10×10^(−4) mol/L)on Ti6Al4V alloy for the first time to promote soft tissue sealing around dental implants.The corrosion resistance of Gd^(3+)-modified PHBV-coated Ti6Al4V was studied by electrochemical and immersion tests,respectively,whereas CCK-8 and RT-PCR evaluated the biocompatibility to human gingival fibroblasts(HGFs)and human umbilical vein endothelial cells(HUVECs).It was found that the Gd^(3+)-modified PHBV coating could enhance the corrosion resistance of Ti6Al4V.In vitro cell tests showed that PHBV coatings with and without Gd^(3+) addition could promote adhesion and proliferation of HGFs and HUVECs,showing a Gd^(3+) content-dependent manner.Moreover,it was found that the PDA-PHBV@1Gd showed the best proliferation to HGFs by up-regulating gene expressions of VINCULIN,ITGB1,and ITGA3,whereas the best response to HUVECs with the highest gene expression of eNOS and HIF-1αgenes was found in the PDA-PHBV@5Gd-coated group.
文摘In this study,Gd^(3+)and Bi^(3+)ions act to redshift the emission band to orange region,and to enhance significantly the maximum emission of YAG:Ce^(3+).On account that size mismatch between the host and the doped Gd^(3+)ion,the crystal structure turns soft,and the emission spectra are not tuned from 540 to 570 nm but decreased the emission intensity.Accordingly,an effective way to increase emission intensity is to introduce Bi^(3+)ion into the YAG:Ce^(3+),Gd^(3+)phosphors.Experimental results show partial overlapping between the emission band of Bi^(3+)ion and the excitation band of Ce^(3+)ion,indicating that the energy transfer from Bi^(3+)to Ce^(3+)ions exists in the(Y_(1.94)Ce_(0.06)Gd)Al_(5)O_(12):Bi^(3+)phosphor.Bi^(3+)ion can serve as the activator to provide energy for Ce^(3+)ion via cross relaxation phenomenon.Therefore,the(Y_(1.94)Ce_(0.06)Gd)Al_(5)O_(12):Bi^(3+)phosphor could have potential applications in warm white LEDs.
文摘γ-globulin is a globulin which possesses immune special characteristic. Steven et al. investigated the binding of Gd<sup>3+</sup> to non-immune rabbit immunoglobulin G and its fragments by measurements of the enhancement of the solvent-water
文摘In this study, a series of Gd^(3+)-doped mixed Ni-Cu-Zn ferrites with composition of Zn_(0.5)Ni_(0.3)Cu_(0.2)Fe_(2-x)Gd_(x)O_(4)(x = 0, 0.025, 0.05, 0.075, 0.1) was prepared using self-ignition sol-gel method. The prepared nanoparticles with an average size ranging from 22 to 26 nm show a single-phase cubic structure belonging to the spinel matrix. A rise in the Gd^(3+)concentration leads to an increase in crystallite size and lattice parameter. In Fourier transform infrared spectra, two main absorption bands belonging to the spinel structure are observed. The high-frequency bands(v_(1)) represent the tetrahedral complex, while the lowfrequency bands(v_(2)) signify the octahedral complex. The optical bandgap of the nanoferrites is found within the range of 2.91 to 2.41 eV, depending on their size. The magnetic characteristics of the material,such as saturation magnetization and coercivity are significantly altered with the concentration of Gd^(3+)in the solution. Using Rhodamine B(RhB) as a model organic pollutant, an in-depth investigation of the photocatalytic activity of the compounds was carried out. The present outcomes show that adding an adequate amount of Gd^(3+)significantly enhances the number of hydroxyl radicals produced by the ferrite,in turn, increasing the photocatalytic activity of the material. Mechanism elucidated by scavenger studies reveals that ·OH and holes are the primary reactive radicals responsible for the degradation process.Prepared photocatalysts show an insignificant performance loss in five consecutive cycles. Thus, it is concluded that these photocatalysts are highly suitable for the remediation of dye-contaminated wastewater.
基金supported by the DST-SERB,New Delhi,India (EMR/000228/2017)TEQIP-Ⅲ,Ministry of Education,Government of India。
文摘Cubic phase Tm^(3+)/Yb^(3+):Y_(2)O_(3) and Tm^(3+)/Yb^(3+)/Gd^(3+):Y_(2)O_(3) phosphors were prepared by low temperature combustion technique for upconversion emission in UV-visible range.The 980 nm excitation has generated UV emission at 314 nm in tridoped phosphor due to the energy transfer from Tm^(3+) to Gd^(3+)ion.Characteristic emission bands from Tm^(3+) are also observed in both the phosphors.Thermally coupled Stark sublevels ^(1)G_(4(a))(476 nm) and ^(1)G_(4(b))(488 nm) of Tm^(3+) ion were utilised for optical thermometry using fluorescent intensity ratio(FIR) method.The result shows that maximum absolute sensitivity in tridoped phosphor is observed to be 1.33 × 10^(-3) K^(-1) at 298 K.Moreover,temperature rise of phosphor at various pump power densities was also measured and it is estimated to achieve 407 K at the pump power density of 38.46 W/cm^(2).
