Absolute quantum yield （Ф） is one of the most important parameters to evaluate the potential of novel materials. Lanthanide complexes EuxGd1-x（TTA）3phens are synthesized with the ratio of Gd3＋ dopant concentrati...Absolute quantum yield （Ф） is one of the most important parameters to evaluate the potential of novel materials. Lanthanide complexes EuxGd1-x（TTA）3phens are synthesized with the ratio of Gd3＋ dopant concentration ranging from 10% to 90% to improve the absolute quantum yield. EuxGd1-x（TTA）3phens possess similar infrared and ultraviolet spectra, showing that they have similar molecular structures. The absolute emission quantum yields of EuxGd1-x（TTA）3phens are determined using a fluoromax-4 spectrofluorometer equipped with an integrating sphere. The fluorescence lifetimes of the EuxGd1-x（TTA）3phens are measured in the same experiment. It was found that both absolute quantum yields and fluorescence lifetimes of EuxGd1-x（TTA）3phens are of quasi-periodic variation with the change of the Gd3. dopant concentrations. The absolute quantum efficiency and fluorescence lifetime vary with respect to the Gd content in an opposite fashion, indicating that the rate of energy absorption by the EuxGd1-x（TTA）3phens and the conversion to light energy is critical for the absolute quantum efficiency. The radiative rate constant Kr and non-radiative rate constant Knr are calculated. The dependence of Kr and Knr on the Gd3＋ dopant concentrations is very similar to that of absolute quantum efficiency. The radiation rate constant Kr and absolute quantum efficiency have a linear relationship.展开更多
Magneto-dielectric properties of Co_(2)Z ferrite materials are tuned via Gd doping for applications in high-frequency antennas and filters in the present work.Ba_(3)Co_(2)Fe_(24-x)Gd_(x)O_(41)(x=0.00,0.05,0.10,0.15,an...Magneto-dielectric properties of Co_(2)Z ferrite materials are tuned via Gd doping for applications in high-frequency antennas and filters in the present work.Ba_(3)Co_(2)Fe_(24-x)Gd_(x)O_(41)(x=0.00,0.05,0.10,0.15,and 0.20)materials are successfully prepared by using solid-state method at 925℃for 4 h with 2.5-wt%Bi_(2)O_(3)sintering aids.The content of Gd^(3+)ion can affect micromorphology,grain size,bulk density,and magneto-dielectric properties of the ferrite.With Gd^(3+)ion content increasing,saturation magnetization(Ms)first increases and then decreases.The maximum value of Ms is 44.86 emu/g at x=0.15.Additionally,sites occupied by Gd^(3+)ions can change magnetic anisotropy constant of the ferrite.Magnetocrystalline anisotropy constant(K_1)is derived from initial magnetization curve,and found to be related to spin-orbit coupling and intersublattice interactions between metal ions.The real part of magnetic permeability(μ′)and real part of dielectric permittivity(ε′)are measured in a frequency range of 10 MHz-1 GHz.When x=0.15,material has excellent magneto-dielectric properties(μ′≈12.2 andε′≈17.61),low magnetic loss(tanδμ≈0.03 at 500 MHz),and dielectric loss(tanδε≈0.04 at 500 MHz).The results show that Gd-doped Co_(2)Z ferrite has broad application prospects in multilayer filters and high-frequency antennas.展开更多
It is anticipated to remove highly hazardous tetracycline antibiotic from aqueous solution photocatalytically by using Gd doped spinal ferrite.In this work,both ZnFe_(2)O_(4)and Gd doped ZnFe_(2)O_(4)photocatalysts we...It is anticipated to remove highly hazardous tetracycline antibiotic from aqueous solution photocatalytically by using Gd doped spinal ferrite.In this work,both ZnFe_(2)O_(4)and Gd doped ZnFe_(2)O_(4)photocatalysts were hydrothermally fabricated and characterized by different techniques.The spherical photocatalysts show extended photocatalytic removal efficiency under visible light.The optimized sample(ZnFe_(1.96)Cd_(0.04)O_(4))removes 78%antibiotic in 80 min.Moreover,under simulated solar light irradiation,the rate of hydrogen produced from water splitting photocatalysis with ZnFe_(1.96)Cd_(0.04)O_(4)reaches 230.4μmol/(g h).These increased activities are attributed to the increased specific surface area,the expanded light absorption range and the enhanced charge separation realized by doping Gd.According to the charge trapping study,both superoxide(·O_(2)^(-))and hydroxyl radicals(·OH)were the major active species in the process of removing antibiotic.This research provides a feasible way to fabricate low cost photocatalysts for the eradication of highly hazardous pollutants from aqueous solution.展开更多
Mesenchymal stem cells(MSCs)hold great promise in regenerative medicine and received overwhelm-ing concerns to promote their therapeutic effects.Owing to the shortage of MSCs-specific biomarkers,bimodal imaging nanopr...Mesenchymal stem cells(MSCs)hold great promise in regenerative medicine and received overwhelm-ing concerns to promote their therapeutic effects.Owing to the shortage of MSCs-specific biomarkers,bimodal imaging nanoprobes with integrated complementary information are of great importance in ameliorating the efficacy of MSCs terminal tracking.In this study,a noninvasive dual-mode imaging nanoprobe with enhanced detection sensitivity and spatial resolution based on alloyed Gd:AgInS_(2)/ZnS quantum dots(QDs)was first fabricated through a microwave-assisted heating method.The QDs with red emissive fluorescence exhibit excellent biocompatibility in MSCs under a confocal microscope.As for magnetic resonance imaging(MRI),the longitudinal relaxation rate of 11.1420 mM^(-1) S^(-1) of Gd:AgInS_(2)/ZnS QDs was achieved,which was 1.7 times higher than that of commercial MRI contrast agent(6.4667 mM^(-1) S^(-1)).Furthermore,the cellular internalization of Gd:AgInS_(2)/ZnS QDs exerts no significant effect on the adipogenesis of MSCs and is conducive to the observation of further adipogenic differentiation.Our work helps to verify the promising prospect to develop a bimodal nanoprobe of fluorescence/MRI based on Gd:AgInS_(2)/ZnS QDs,which could monitor the differentiation and migration of MSCs for further therapeu-tic approach.展开更多
In this manuscript,we report the hydrothermally prepared rGO/Gd@ZnO nanocomposite for the utilization of photocatalytic Rh B(rhodamine B)dye degradation.The required characterization techniques were carried out to ana...In this manuscript,we report the hydrothermally prepared rGO/Gd@ZnO nanocomposite for the utilization of photocatalytic Rh B(rhodamine B)dye degradation.The required characterization techniques were carried out to analyse the structural,morphological,chemical,environmental and optical behaviour of the prepared nanoparticles.Photocatalytic efficiency of the prepared nanoparticles was studied by Rh B dye degradation upon UV-Vis-light illumination which reveals that composite catalyst degrades the dye molecule about 91%after 40 min of irradiation.On comparing the higher degradation efficiency of the rGO/Gd@ZnO nanocomposite with that of ZnO and Gd doped ZnO,it reveals a greater reduction of charge carriers'recombination,higher visible-light utilization and higher adsorption efficiency.Elemental trapping experiment and recycling test were conducted to study the influence of active radicals for the degradation reaction and to know the stability of the prepared nanocomposite,respectively.Hence,this rGO supported Gd doped ZnO nanocomposite can provide a new path way in preparing a highly efficient photocatalyst for organic pollutant degradation at large.展开更多
To simulate the effects of burnable poison doping in nuclear fuel UO2,Er2O3(or Gd2O3)-doped CeO2 pellets were prepared. Changes in lattice constant and atomic disordering for CeO2 due to the Er2O3 and Gd2O3 doping wer...To simulate the effects of burnable poison doping in nuclear fuel UO2,Er2O3(or Gd2O3)-doped CeO2 pellets were prepared. Changes in lattice constant and atomic disordering for CeO2 due to the Er2O3 and Gd2O3 doping were measured by means of XRD and XAFS. By the Er2O3 doping,the lattice constant decreased,and a disordering of lattice structure was induced in the samples. The doping with Er2O3 also induced the disordering of atomic arrangement around Er atoms,which was observed through the change in XAFS spectra. In contrast,the effect of Gd2O3 doping was smaller than that of Er2O3 doping. The result was discussed in terms of ionic size of dopants in CeO2 crystal.展开更多
Reactive oxygen species are essential in photocatalytic water treatment.In this paper,Gd doped carbon nitride(CN)photocatalysts were prepared by simple thermal polymerization for the photocatalytic degradation of tetr...Reactive oxygen species are essential in photocatalytic water treatment.In this paper,Gd doped carbon nitride(CN)photocatalysts were prepared by simple thermal polymerization for the photocatalytic degradation of tetracycline under visible light irradiation.The photodegradation rate of 1.OGdCN is as high as 95%in 18 min,and the photocatalytic performance is much higher than that of CN.The improvement of photocatalytic performance is mainly attributed to the fact that Gd ion implantation directly provides active sites for oxygen activation and induces the formation of N vacancies.The results of characterizations show that the introduction of Gd in CN can improve the conversion ability of activated oxygen,carrier separation and energy band structure adjustment.Therefore,1.0GdCN photocatalyst can be employed for efficient photocatalytic synthesis of tetracycline.Furthermore,three ways of photocatalytic degradation of tetracycline were revealed by high performance liquid chromatographymass spectrometry.This work provides insights into the doping strategy of CN to improve the production of reactive oxygen species for environmental remediation.展开更多
A series of KY3F10 nanophosphors doped with Gd3＋, Ce3＋ and Eu3＋ ions were obtained with the use of a co-precipitation method. The resulting products were white precipitates, consisting of spherical particles with d...A series of KY3F10 nanophosphors doped with Gd3＋, Ce3＋ and Eu3＋ ions were obtained with the use of a co-precipitation method. The resulting products were white precipitates, consisting of spherical particles with diameter about 150-200 nm, which was confirmed using transmission electron microscopy （TEM） technique. Powder X-ray diffraction （XRD） and energy dispersive X-ray analysis （EDX） measurements confirmed appropriate structures of the nanoparticles obtained. Spectroscopic properties of the prod- ucts were examined on the basis of the measured excitation/emission spectra and luminescence decay curves. The synthesized sam- ples showed orange-red luminescence, characteristic for Eu3＋ ions. The reaction process was performed in required alkaline pH ad- justed with the use of ethylenediaminetetraacetic acid （EDTA） and potassium hydroxide. The samples containing large amounts of Gd3＋ dooant ions exhibited a tendencv to form nroducts with different momhologies.展开更多
Enhancing the electrocatalytic activity of the electrode materials,specifically oxygen reduction reaction(ORR),at lower operating temperatures(<600℃)is the prime rank to realize the commercialization of solid oxid...Enhancing the electrocatalytic activity of the electrode materials,specifically oxygen reduction reaction(ORR),at lower operating temperatures(<600℃)is the prime rank to realize the commercialization of solid oxide fuel cells(SOFCs)research.Herein,a new hexagonal structure-based cathode material was developed with the co-doping of Gd_(2)O_(3)and Cr_(2)O_(3)of parent SrFe_(12)O_(19)oxide,respectively.At 550-475℃,Sr_(0.90)Gd_(0.10)Fe_(11.90)Cr_(0.10)O_(19)(SFO-10)cathode sample leading to the large peak power density(PPD)of 395 mW/cm^(2),has appropriate surface oxygen defects(O_(β))up to 17%,as verified by X-ray photoelectron microscopy(XPS).Theoretical calculations reveal that the co-doping of Gd and Cr oxides creates lattice disorder at the hexagonal lattice,which decreases the energy barrier for ion transport and enhances the electrocatalytic characteristics of ORR.Consequently,the SFO-10 cathode shows a favorable ORR activity with the least lower polarization resistance(ASR)at 550℃with gadolinium-doped ceria(GDC)electrolyte.This work provides a self-assembled single-phase hexagonal cathode to accelerate the lowtemperature hindrance of SOFC technology.展开更多
基金supported by the National Natural Science Foundation of China(No.50973003)Anhui Science and TechnologyProgram(Nos.KJ2012B135,KJ2012A217,KJ2012B136,KJ2011A210, 1301042112)+1 种基金Natural Science Foundation of Fuyang Normal College (Nos.2011HJJC02ZD,2011HJJC01ZD,2011HJJC04YB,2010FSKJ01ZD, 2013FSKJ03ZD)Incubator Fund of Scientific and Technological achievements of Fuyang Normal College(Nos.2013KJFH03, 2013KJFH01)
文摘Absolute quantum yield （Ф） is one of the most important parameters to evaluate the potential of novel materials. Lanthanide complexes EuxGd1-x（TTA）3phens are synthesized with the ratio of Gd3＋ dopant concentration ranging from 10% to 90% to improve the absolute quantum yield. EuxGd1-x（TTA）3phens possess similar infrared and ultraviolet spectra, showing that they have similar molecular structures. The absolute emission quantum yields of EuxGd1-x（TTA）3phens are determined using a fluoromax-4 spectrofluorometer equipped with an integrating sphere. The fluorescence lifetimes of the EuxGd1-x（TTA）3phens are measured in the same experiment. It was found that both absolute quantum yields and fluorescence lifetimes of EuxGd1-x（TTA）3phens are of quasi-periodic variation with the change of the Gd3. dopant concentrations. The absolute quantum efficiency and fluorescence lifetime vary with respect to the Gd content in an opposite fashion, indicating that the rate of energy absorption by the EuxGd1-x（TTA）3phens and the conversion to light energy is critical for the absolute quantum efficiency. The radiative rate constant Kr and non-radiative rate constant Knr are calculated. The dependence of Kr and Knr on the Gd3＋ dopant concentrations is very similar to that of absolute quantum efficiency. The radiation rate constant Kr and absolute quantum efficiency have a linear relationship.
基金the National Key Research and Development Program of China(Grant No.2022YFB3504800)the National Natural Science Foundation of China(Grant Nos.61901142,52003256,and 51902037)the Natural Science Foundation of Shanxi Province,China(Grant No.201901D211259)。
文摘Magneto-dielectric properties of Co_(2)Z ferrite materials are tuned via Gd doping for applications in high-frequency antennas and filters in the present work.Ba_(3)Co_(2)Fe_(24-x)Gd_(x)O_(41)(x=0.00,0.05,0.10,0.15,and 0.20)materials are successfully prepared by using solid-state method at 925℃for 4 h with 2.5-wt%Bi_(2)O_(3)sintering aids.The content of Gd^(3+)ion can affect micromorphology,grain size,bulk density,and magneto-dielectric properties of the ferrite.With Gd^(3+)ion content increasing,saturation magnetization(Ms)first increases and then decreases.The maximum value of Ms is 44.86 emu/g at x=0.15.Additionally,sites occupied by Gd^(3+)ions can change magnetic anisotropy constant of the ferrite.Magnetocrystalline anisotropy constant(K_1)is derived from initial magnetization curve,and found to be related to spin-orbit coupling and intersublattice interactions between metal ions.The real part of magnetic permeability(μ′)and real part of dielectric permittivity(ε′)are measured in a frequency range of 10 MHz-1 GHz.When x=0.15,material has excellent magneto-dielectric properties(μ′≈12.2 andε′≈17.61),low magnetic loss(tanδμ≈0.03 at 500 MHz),and dielectric loss(tanδε≈0.04 at 500 MHz).The results show that Gd-doped Co_(2)Z ferrite has broad application prospects in multilayer filters and high-frequency antennas.
基金Project supported by the National Natural Science Foundation of China(22268003,52272287)。
文摘It is anticipated to remove highly hazardous tetracycline antibiotic from aqueous solution photocatalytically by using Gd doped spinal ferrite.In this work,both ZnFe_(2)O_(4)and Gd doped ZnFe_(2)O_(4)photocatalysts were hydrothermally fabricated and characterized by different techniques.The spherical photocatalysts show extended photocatalytic removal efficiency under visible light.The optimized sample(ZnFe_(1.96)Cd_(0.04)O_(4))removes 78%antibiotic in 80 min.Moreover,under simulated solar light irradiation,the rate of hydrogen produced from water splitting photocatalysis with ZnFe_(1.96)Cd_(0.04)O_(4)reaches 230.4μmol/(g h).These increased activities are attributed to the increased specific surface area,the expanded light absorption range and the enhanced charge separation realized by doping Gd.According to the charge trapping study,both superoxide(·O_(2)^(-))and hydroxyl radicals(·OH)were the major active species in the process of removing antibiotic.This research provides a feasible way to fabricate low cost photocatalysts for the eradication of highly hazardous pollutants from aqueous solution.
基金financially supported by the National Natural Science Foundation of China(NSFC,No.62074044)the Zhongshan-Fudan Joint Innovation Center,and the Jihua Laboratory Projects of Guangdong Province(No.X190111UZ190).
文摘Mesenchymal stem cells(MSCs)hold great promise in regenerative medicine and received overwhelm-ing concerns to promote their therapeutic effects.Owing to the shortage of MSCs-specific biomarkers,bimodal imaging nanoprobes with integrated complementary information are of great importance in ameliorating the efficacy of MSCs terminal tracking.In this study,a noninvasive dual-mode imaging nanoprobe with enhanced detection sensitivity and spatial resolution based on alloyed Gd:AgInS_(2)/ZnS quantum dots(QDs)was first fabricated through a microwave-assisted heating method.The QDs with red emissive fluorescence exhibit excellent biocompatibility in MSCs under a confocal microscope.As for magnetic resonance imaging(MRI),the longitudinal relaxation rate of 11.1420 mM^(-1) S^(-1) of Gd:AgInS_(2)/ZnS QDs was achieved,which was 1.7 times higher than that of commercial MRI contrast agent(6.4667 mM^(-1) S^(-1)).Furthermore,the cellular internalization of Gd:AgInS_(2)/ZnS QDs exerts no significant effect on the adipogenesis of MSCs and is conducive to the observation of further adipogenic differentiation.Our work helps to verify the promising prospect to develop a bimodal nanoprobe of fluorescence/MRI based on Gd:AgInS_(2)/ZnS QDs,which could monitor the differentiation and migration of MSCs for further therapeu-tic approach.
基金the Priority Research Centers Program through the National Research Foundation of Korea(NRF)funded by Ministry of Education(2014R1A6A1031189)。
文摘In this manuscript,we report the hydrothermally prepared rGO/Gd@ZnO nanocomposite for the utilization of photocatalytic Rh B(rhodamine B)dye degradation.The required characterization techniques were carried out to analyse the structural,morphological,chemical,environmental and optical behaviour of the prepared nanoparticles.Photocatalytic efficiency of the prepared nanoparticles was studied by Rh B dye degradation upon UV-Vis-light illumination which reveals that composite catalyst degrades the dye molecule about 91%after 40 min of irradiation.On comparing the higher degradation efficiency of the rGO/Gd@ZnO nanocomposite with that of ZnO and Gd doped ZnO,it reveals a greater reduction of charge carriers'recombination,higher visible-light utilization and higher adsorption efficiency.Elemental trapping experiment and recycling test were conducted to study the influence of active radicals for the degradation reaction and to know the stability of the prepared nanocomposite,respectively.Hence,this rGO supported Gd doped ZnO nanocomposite can provide a new path way in preparing a highly efficient photocatalyst for organic pollutant degradation at large.
基金Project supported by Japan Society for the Promotion of Science (JSPS) Research (Grant-in-aid for Scientific Research B No. 21360469)the Osaka Nuclear Science Association (ONSA),the XAFS Measurements at KEK-PF were Performed with the Approval of KEK (2009G536)
文摘To simulate the effects of burnable poison doping in nuclear fuel UO2,Er2O3(or Gd2O3)-doped CeO2 pellets were prepared. Changes in lattice constant and atomic disordering for CeO2 due to the Er2O3 and Gd2O3 doping were measured by means of XRD and XAFS. By the Er2O3 doping,the lattice constant decreased,and a disordering of lattice structure was induced in the samples. The doping with Er2O3 also induced the disordering of atomic arrangement around Er atoms,which was observed through the change in XAFS spectra. In contrast,the effect of Gd2O3 doping was smaller than that of Er2O3 doping. The result was discussed in terms of ionic size of dopants in CeO2 crystal.
基金Project supported by the National Key Research and Development Program of China(2022YFF1100804)Natural Science Foundation of Xinjiang Uygur Auonomous Region(2022D01C456)+3 种基金Guangdong Basic and Applied Basic Research Foundation(2023A1515011736,2021A1515010671)Guangdong Province Scientific Research Platform Project(2022ZDZX4046,2023ZDZX4052,2020KTSCX135)Guangdong Province Specialized Scientific Research Fund Projects(20192019B121201004)High Level Talents Introduction Project of"Pearl River Talent Plan"in Guangdong Province(2019CX01L308)。
文摘Reactive oxygen species are essential in photocatalytic water treatment.In this paper,Gd doped carbon nitride(CN)photocatalysts were prepared by simple thermal polymerization for the photocatalytic degradation of tetracycline under visible light irradiation.The photodegradation rate of 1.OGdCN is as high as 95%in 18 min,and the photocatalytic performance is much higher than that of CN.The improvement of photocatalytic performance is mainly attributed to the fact that Gd ion implantation directly provides active sites for oxygen activation and induces the formation of N vacancies.The results of characterizations show that the introduction of Gd in CN can improve the conversion ability of activated oxygen,carrier separation and energy band structure adjustment.Therefore,1.0GdCN photocatalyst can be employed for efficient photocatalytic synthesis of tetracycline.Furthermore,three ways of photocatalytic degradation of tetracycline were revealed by high performance liquid chromatographymass spectrometry.This work provides insights into the doping strategy of CN to improve the production of reactive oxygen species for environmental remediation.
基金Project supported by the Polish National Science Centre(2015/17/N/ST5/01947)
文摘A series of KY3F10 nanophosphors doped with Gd3＋, Ce3＋ and Eu3＋ ions were obtained with the use of a co-precipitation method. The resulting products were white precipitates, consisting of spherical particles with diameter about 150-200 nm, which was confirmed using transmission electron microscopy （TEM） technique. Powder X-ray diffraction （XRD） and energy dispersive X-ray analysis （EDX） measurements confirmed appropriate structures of the nanoparticles obtained. Spectroscopic properties of the prod- ucts were examined on the basis of the measured excitation/emission spectra and luminescence decay curves. The synthesized sam- ples showed orange-red luminescence, characteristic for Eu3＋ ions. The reaction process was performed in required alkaline pH ad- justed with the use of ethylenediaminetetraacetic acid （EDTA） and potassium hydroxide. The samples containing large amounts of Gd3＋ dooant ions exhibited a tendencv to form nroducts with different momhologies.
基金Project supported by the Scientific and Technological Innovation Team of Nanjing(NINGJIAOGAOSHI 2021 No.16)。
文摘Enhancing the electrocatalytic activity of the electrode materials,specifically oxygen reduction reaction(ORR),at lower operating temperatures(<600℃)is the prime rank to realize the commercialization of solid oxide fuel cells(SOFCs)research.Herein,a new hexagonal structure-based cathode material was developed with the co-doping of Gd_(2)O_(3)and Cr_(2)O_(3)of parent SrFe_(12)O_(19)oxide,respectively.At 550-475℃,Sr_(0.90)Gd_(0.10)Fe_(11.90)Cr_(0.10)O_(19)(SFO-10)cathode sample leading to the large peak power density(PPD)of 395 mW/cm^(2),has appropriate surface oxygen defects(O_(β))up to 17%,as verified by X-ray photoelectron microscopy(XPS).Theoretical calculations reveal that the co-doping of Gd and Cr oxides creates lattice disorder at the hexagonal lattice,which decreases the energy barrier for ion transport and enhances the electrocatalytic characteristics of ORR.Consequently,the SFO-10 cathode shows a favorable ORR activity with the least lower polarization resistance(ASR)at 550℃with gadolinium-doped ceria(GDC)electrolyte.This work provides a self-assembled single-phase hexagonal cathode to accelerate the lowtemperature hindrance of SOFC technology.
