导模法是一种超高熔点晶体的有效生长方法,可以生长高质量、大尺寸、高掺杂的Er:Lu_(2)O_(3)晶体。本文测试了导模法生长的Er:Lu_(2)O_(3)晶体的荧光发射谱及连续激光特性,在室温下获得了斜效率为23.1%的2.85μm连续激光输出,最高输出功...导模法是一种超高熔点晶体的有效生长方法,可以生长高质量、大尺寸、高掺杂的Er:Lu_(2)O_(3)晶体。本文测试了导模法生长的Er:Lu_(2)O_(3)晶体的荧光发射谱及连续激光特性,在室温下获得了斜效率为23.1%的2.85μm连续激光输出,最高输出功率5.24 W。80 min功率RMS(Root mean square)稳定性优于1.4%,不同输出功率水平的激光光束质量M^(2)因子优于2.17。实验结果表明,导模法生长的Er:Lu_(2)O_(3)激光晶体具备输出高功率、高效率中红外激光的能力。展开更多
The kinetics of isomerisation of 1-butene over Lu2O3/SiO2 catalyst has beeninvestigated by the flow-recirculation glass reactor. The heats of adsorption for 1-butene,2-butene and water were deteched by the pulse metho...The kinetics of isomerisation of 1-butene over Lu2O3/SiO2 catalyst has beeninvestigated by the flow-recirculation glass reactor. The heats of adsorption for 1-butene,2-butene and water were deteched by the pulse method. The kinetics of isomerizationof 1-butene obeys the L-H mechaniasm Kinetic equation. We observed that L-H kineticequation with two parameters is the good-conditioned equation. The L-H kinetic equation with more than three paramters is a ill-conditioned equation. The condition numberof normal equation increases with the increase of paramter numbers for kinetic equation.In addition, we observed that the condition number is not less than the square of ratio oflong to short in column vector for the coefficient matrix of contradiction equation.展开更多
In this paper,effect of two strategies on afterglow behavior of Lu_(2)O_(3):Eu single crystal scintillato r,Pr^(3+)codoping and solid solution with Sc_(2)O_(3),were studied systematically.Two groups of Lu_(2)O_(3):5 a...In this paper,effect of two strategies on afterglow behavior of Lu_(2)O_(3):Eu single crystal scintillato r,Pr^(3+)codoping and solid solution with Sc_(2)O_(3),were studied systematically.Two groups of Lu_(2)O_(3):5 at%Eu,x at%Pr(x=0,0.2,0.5,1,2 and 5)and(Lu1-yScy)_(2)O_(3):5 at%Eu(y=0,20 at%,50 at%and 70 at%)single crystals were grown by floating zone(FZ)method in air atmosphere.The structures of as-grown crystals were determined by X-ray diffraction(XRD).The scintillation,photoluminescence properties and carrier trap states were investigated through afterglow,X-ray excitation luminescence(XEL),transmittance,photoluminescence excitation(PLE)and photoluminescence(PL),PL decay and thermal stimulated luminescence(TSL)curves.It is found that with the increase of Pr^(3+)concentration,the afterglow level of the system decreases at the expense of scintillation luminescence efficiency.Meanwhile,although Sc_(2)O_(3):Eu presents much lower afterglow intensity than Lu_(2)O_(3):Eu,the addition of Sc_(2)O_(3)will just increase the afterglow level of the(Lu1-yScy)_(2)O_(3):5 at%Eu single crystal system.Possible mechanisms for above phenomena are discussed based on experimental results.展开更多
The difficulty of reducing the diameter of lutetium oxide(Lu_(2)O_(3))continuous fibers below 50μm not only limits the flexibility of the sample but also seriously affects their application and development in high-en...The difficulty of reducing the diameter of lutetium oxide(Lu_(2)O_(3))continuous fibers below 50μm not only limits the flexibility of the sample but also seriously affects their application and development in high-energy lasers.In this work,a Lu-containing precursor with high ceramic yield was used as raw material,fiberized into precursor fibers by dry spinning.The pressure-assisted water vapor pretreatment(PAWVT)method was creatively proposed,and the effect of pretreatment temperature on the ceramization behavior of the precursor fibers was studied.By regulating the decomposition behavior of organic components in the precursor,the problem of fiber pulverization during heat treatment was effectively solved,and the Lu_(2)O_(3) continuous fibers with a diameter of 40μm were obtained.Compared with the current reported results,the diameter was reduced by about 50%,successfully breaking through the diameter limitation of Lu_(2)O_(3) continuous fibers.In addition,the tensile strength,elastic modulus,flexibility,and temperature resistance of Lu_(2)O_(3) continuous fibers were researched for the first time.The tensile strength and elastic modulus of Lu_(2)O_(3) continuous fibers were 373.23 MPa and 31.55 GPa,respectively.The as-obtained flexible Lu_(2)O_(3) continuous fibers with a limit radius of curvature of 3.5-4.5 mm had a temperature resistance of not lower than 1300℃,which established a solid foundation for the expansion of their application form in the field of high-energy lasers.展开更多
As a binary system of BaO-Lu_2O_3-SiO_2 ternary system, Lu_2O_3-SiO_2 system was optimized and calculated by CALPHAD approach based on available phase diagram and relevant thermodynamic data of RE_2O_3-SiO_2（RE=Lu,Y...As a binary system of BaO-Lu_2O_3-SiO_2 ternary system, Lu_2O_3-SiO_2 system was optimized and calculated by CALPHAD approach based on available phase diagram and relevant thermodynamic data of RE_2O_3-SiO_2（RE=Lu,Yb,Y） binary systems as well as our experimental data of Lu_2O_3-SiO_2 system obtained by quenching experiment. The Gibbs free energy of high temperature solution was described by an ionic two-sublattice model as（Lu^（3＋））P（O^（2-）, SiO_2~0）Q. The calculated phase diagram below 1873 K was in good agreement with experimental data at 1573, 1773 and 1873 K. The calculated Gibbs energies of two intermediate phases Lu_2SiO_5 and Lu_2Si_2O_7, the activity of Lu_2O_3 and SiO_2 and specific heat capacities of intermediate phases agreed well with experimental results of Y_2O_3-SiO_2 system. This tentative study will offer help for the research of single-phase phosphor and related metallurgical slags, refractories, high-temperature superconductivity material systems.展开更多
The Yb:Lu_(2)O_(3)precursor made up of spherical particles was synthesized through the co-precipitation method in the water/ethanol solvent.The 5 at% Yb:Lu_(2)O_(3)powder is in the cubic phase after calcination at 110...The Yb:Lu_(2)O_(3)precursor made up of spherical particles was synthesized through the co-precipitation method in the water/ethanol solvent.The 5 at% Yb:Lu_(2)O_(3)powder is in the cubic phase after calcination at 1100℃ for 4 h.The powder also consists of spherical nanoparticles with the average particle and grain sizes of 96 and 49 nm,respectively.The average grain size of the pre-sintered ceramic sample is 526 nm and that of the sample by hot isostatic pressing grows to 612 nm.The 1.0 mm-thick sample has an in-line transmittance of 81.6%(theoretical value of 82.2%)at 1100 nm.The largest absorption cross-section at 976 nm is 0.96×1^(0-20)cm^(2) with the emission cross-section at 1033 nm of 0.92×10^(-20)cm^(2) and the gain cross sections are calculated with the smallest population inversion parameter β of 0.059.The highest slope efficiency of 68.7% with the optical efficiency of 65.1% is obtained at 1033.3 nm in quasi-continuous wave(QCW)pumping.In the case of continuous wave(CW)pumping,the highest slope efficiency is 61.0% with the optical efficiency of 54.1%.The obtained laser performance indicates that Yb:Lu_(2)O_(3)ceramics have excellent resistance to thermal load stresses,which shows great potential in high-power solid-state laser applications.展开更多
In the present computational study,we found that Er:Lu_(2)O_(3)materials have promise for application in laser applications.The crystal structure and the electronic and optical properties of Er:Lu_(2)O_(3)materials we...In the present computational study,we found that Er:Lu_(2)O_(3)materials have promise for application in laser applications.The crystal structure and the electronic and optical properties of Er:Lu_(2)O_(3)materials were studied using first-principle calculations under the framework of density functional theory.Based on the experimental and calculated results,the structure of Lu_(2)O_(3)was established.The calculated results show that doping by Er^(3+)can effectively improve its absorption coefficient in the ultraviolet region and improve the static dielectric constant of Lu_(2)O_(3).As the doping concentration of Er^(3+)increases,the energy of the valence band electrons excited to the conduction band decreases,and the transition is more likely to occur.The absorption coefficient,reflectance,and electron energy loss spectroscopy are bathochromic shifted.The Lu_(2-x)Er_(x)O_(3)(0<x<0.09375)system still retains a low absorption coefficient reflectance in the mid-infrared and visible regions.Our calculations therefore show that rare earth doping can effectively regulate the electronic structure and optical properties of Lu_(2)O_(3).展开更多
文摘导模法是一种超高熔点晶体的有效生长方法,可以生长高质量、大尺寸、高掺杂的Er:Lu_(2)O_(3)晶体。本文测试了导模法生长的Er:Lu_(2)O_(3)晶体的荧光发射谱及连续激光特性,在室温下获得了斜效率为23.1%的2.85μm连续激光输出,最高输出功率5.24 W。80 min功率RMS(Root mean square)稳定性优于1.4%,不同输出功率水平的激光光束质量M^(2)因子优于2.17。实验结果表明,导模法生长的Er:Lu_(2)O_(3)激光晶体具备输出高功率、高效率中红外激光的能力。
文摘The kinetics of isomerisation of 1-butene over Lu2O3/SiO2 catalyst has beeninvestigated by the flow-recirculation glass reactor. The heats of adsorption for 1-butene,2-butene and water were deteched by the pulse method. The kinetics of isomerizationof 1-butene obeys the L-H mechaniasm Kinetic equation. We observed that L-H kineticequation with two parameters is the good-conditioned equation. The L-H kinetic equation with more than three paramters is a ill-conditioned equation. The condition numberof normal equation increases with the increase of paramter numbers for kinetic equation.In addition, we observed that the condition number is not less than the square of ratio oflong to short in column vector for the coefficient matrix of contradiction equation.
基金supported by National Natural Science Foundation of China(12175130,11875187)the Opening Project of State Key Laboratory of Key Laboratory of Transparent Opto-functional Inorganic Materials,Chinese Academy of Sciences(KLTOIM202002)。
文摘In this paper,effect of two strategies on afterglow behavior of Lu_(2)O_(3):Eu single crystal scintillato r,Pr^(3+)codoping and solid solution with Sc_(2)O_(3),were studied systematically.Two groups of Lu_(2)O_(3):5 at%Eu,x at%Pr(x=0,0.2,0.5,1,2 and 5)and(Lu1-yScy)_(2)O_(3):5 at%Eu(y=0,20 at%,50 at%and 70 at%)single crystals were grown by floating zone(FZ)method in air atmosphere.The structures of as-grown crystals were determined by X-ray diffraction(XRD).The scintillation,photoluminescence properties and carrier trap states were investigated through afterglow,X-ray excitation luminescence(XEL),transmittance,photoluminescence excitation(PLE)and photoluminescence(PL),PL decay and thermal stimulated luminescence(TSL)curves.It is found that with the increase of Pr^(3+)concentration,the afterglow level of the system decreases at the expense of scintillation luminescence efficiency.Meanwhile,although Sc_(2)O_(3):Eu presents much lower afterglow intensity than Lu_(2)O_(3):Eu,the addition of Sc_(2)O_(3)will just increase the afterglow level of the(Lu1-yScy)_(2)O_(3):5 at%Eu single crystal system.Possible mechanisms for above phenomena are discussed based on experimental results.
基金supported by the Key Program of the National Natural Science Foundation of China (No.52032003)the National Natural Science for Youth Foundation of China (Nos.52102093 and 52202090)+3 种基金the Shandong University Young Scholars Program (No.2016WLJH27)the Fundamental Research Funds for the Central Universities (No.2082019014)the China Postdoctoral Science Foundation (No.2021M690817)the Heilongjiang Provincial Postdoctoral Science Foundation (Nos.LBH-Z21050 and LBH-Z20144).
文摘The difficulty of reducing the diameter of lutetium oxide(Lu_(2)O_(3))continuous fibers below 50μm not only limits the flexibility of the sample but also seriously affects their application and development in high-energy lasers.In this work,a Lu-containing precursor with high ceramic yield was used as raw material,fiberized into precursor fibers by dry spinning.The pressure-assisted water vapor pretreatment(PAWVT)method was creatively proposed,and the effect of pretreatment temperature on the ceramization behavior of the precursor fibers was studied.By regulating the decomposition behavior of organic components in the precursor,the problem of fiber pulverization during heat treatment was effectively solved,and the Lu_(2)O_(3) continuous fibers with a diameter of 40μm were obtained.Compared with the current reported results,the diameter was reduced by about 50%,successfully breaking through the diameter limitation of Lu_(2)O_(3) continuous fibers.In addition,the tensile strength,elastic modulus,flexibility,and temperature resistance of Lu_(2)O_(3) continuous fibers were researched for the first time.The tensile strength and elastic modulus of Lu_(2)O_(3) continuous fibers were 373.23 MPa and 31.55 GPa,respectively.The as-obtained flexible Lu_(2)O_(3) continuous fibers with a limit radius of curvature of 3.5-4.5 mm had a temperature resistance of not lower than 1300℃,which established a solid foundation for the expansion of their application form in the field of high-energy lasers.
基金supported by the National Natural Science Foundation of China(51304086)the Science and Technology Landing Plan for Colleges of Jiangxi Province(KJLD14045)+1 种基金Foundation of Science and Technology Pillar Program in Industrial Field of Jiangxi Province(20123BBE50075)the Program of Qingjiang Excellent Young Talents,Jiangxi University of Science and Technology
文摘As a binary system of BaO-Lu_2O_3-SiO_2 ternary system, Lu_2O_3-SiO_2 system was optimized and calculated by CALPHAD approach based on available phase diagram and relevant thermodynamic data of RE_2O_3-SiO_2（RE=Lu,Yb,Y） binary systems as well as our experimental data of Lu_2O_3-SiO_2 system obtained by quenching experiment. The Gibbs free energy of high temperature solution was described by an ionic two-sublattice model as（Lu^（3＋））P（O^（2-）, SiO_2~0）Q. The calculated phase diagram below 1873 K was in good agreement with experimental data at 1573, 1773 and 1873 K. The calculated Gibbs energies of two intermediate phases Lu_2SiO_5 and Lu_2Si_2O_7, the activity of Lu_2O_3 and SiO_2 and specific heat capacities of intermediate phases agreed well with experimental results of Y_2O_3-SiO_2 system. This tentative study will offer help for the research of single-phase phosphor and related metallurgical slags, refractories, high-temperature superconductivity material systems.
基金supported by the National Key R&D Program of China(Grant No.2017YFB0310500)the National Natural Science Foundation of China(Grant No.61575212)the Key Research Project of the Frontier Science of the Chinese Academy of Sciences(No.QYZDB-SSW-JSC022).
文摘The Yb:Lu_(2)O_(3)precursor made up of spherical particles was synthesized through the co-precipitation method in the water/ethanol solvent.The 5 at% Yb:Lu_(2)O_(3)powder is in the cubic phase after calcination at 1100℃ for 4 h.The powder also consists of spherical nanoparticles with the average particle and grain sizes of 96 and 49 nm,respectively.The average grain size of the pre-sintered ceramic sample is 526 nm and that of the sample by hot isostatic pressing grows to 612 nm.The 1.0 mm-thick sample has an in-line transmittance of 81.6%(theoretical value of 82.2%)at 1100 nm.The largest absorption cross-section at 976 nm is 0.96×1^(0-20)cm^(2) with the emission cross-section at 1033 nm of 0.92×10^(-20)cm^(2) and the gain cross sections are calculated with the smallest population inversion parameter β of 0.059.The highest slope efficiency of 68.7% with the optical efficiency of 65.1% is obtained at 1033.3 nm in quasi-continuous wave(QCW)pumping.In the case of continuous wave(CW)pumping,the highest slope efficiency is 61.0% with the optical efficiency of 54.1%.The obtained laser performance indicates that Yb:Lu_(2)O_(3)ceramics have excellent resistance to thermal load stresses,which shows great potential in high-power solid-state laser applications.
基金Project support by the National Natural Science Foundation of China(51372203.51332004,51571166).
文摘In the present computational study,we found that Er:Lu_(2)O_(3)materials have promise for application in laser applications.The crystal structure and the electronic and optical properties of Er:Lu_(2)O_(3)materials were studied using first-principle calculations under the framework of density functional theory.Based on the experimental and calculated results,the structure of Lu_(2)O_(3)was established.The calculated results show that doping by Er^(3+)can effectively improve its absorption coefficient in the ultraviolet region and improve the static dielectric constant of Lu_(2)O_(3).As the doping concentration of Er^(3+)increases,the energy of the valence band electrons excited to the conduction band decreases,and the transition is more likely to occur.The absorption coefficient,reflectance,and electron energy loss spectroscopy are bathochromic shifted.The Lu_(2-x)Er_(x)O_(3)(0<x<0.09375)system still retains a low absorption coefficient reflectance in the mid-infrared and visible regions.Our calculations therefore show that rare earth doping can effectively regulate the electronic structure and optical properties of Lu_(2)O_(3).
