Methods for transforming rare earth(RE)sulfate into chloride mainly include extraction process with organophosphonic mono-acids or aliphatic acids and precipitation process with ammonium bicarbonate(NH4 HCO3).In this ...Methods for transforming rare earth(RE)sulfate into chloride mainly include extraction process with organophosphonic mono-acids or aliphatic acids and precipitation process with ammonium bicarbonate(NH4 HCO3).In this paper,alkylphenoxy carboxylic acids(HAs)ofp-dodecylphenoxy acetic acid(HA-Ⅰ),pdodecylphenoxypropanoic acid(HA-Ⅱ)and p-dodecylphenoxybutyric acid(HA-Ⅲ),which were liquid at room temperature were synthesized and characterized.The precipitation mechanisms of RE elements with the HAs were investigated and the HA/RE molar ratios of the solid complexes were determined as3:1 by equi-molar series method which accord with the principle of charge balance.Applicability of HAs for the transformation of RE sulfate from concentrated sulfuric acid roasted RE concentrate into chloride via precipitation method was discussed.100%HA-Ⅱwas selected as the liquid organic precipitant without dilution of volatile solvent soracceleration of phase separation by phase-modifiers.The RE sulfate solution can be precipitated by HA-Ⅱafter neutralization with liquid NaOH and stripped with concentrated HCl at room temperature.High concentration of RE chloride of 218.1 g/L with low residue of sulfate radical of 0.536 g/L was obtained.The residual organic precipitant in the raffinate solution was tested to be lower than 8 mg/L at 25℃and the chemical oxygen demand(COD)in wastewater was less than 50 mg/L.展开更多
A novel purification process based on mixer-settlers for high-purity NdClwas developed. Acidic solution and pure NdClsolution were compared to scrub the less-extractable rare earths(REs)(La, Ce, and Pr)from loaded org...A novel purification process based on mixer-settlers for high-purity NdClwas developed. Acidic solution and pure NdClsolution were compared to scrub the less-extractable rare earths(REs)(La, Ce, and Pr)from loaded organic phase. The extractant with low-degree saponification was evaluated to remove the more-extractable element(Sm). Then the RE impurities(La, Ce, Pr, and Sm) in Nd were purified by an integrated process. Furthermore, effect of smuggling behavior on the purification of NdClin mixersettlers was studied. Based on the investigation mentioned above, the pilot-scale purification process for NdClwith a purity of 99.999% was developed, and the total recovery was about 99%.展开更多
The use of low-coherence light is expected to be one of the effective ways to suppress or even eliminate the laser–plasma instabilities that arise in attempts to achieve inertial confinement fusion.In this paper,a re...The use of low-coherence light is expected to be one of the effective ways to suppress or even eliminate the laser–plasma instabilities that arise in attempts to achieve inertial confinement fusion.In this paper,a review of low-coherence high-power laser drivers and related key techniques is first presented.Work at typical low-coherence laser facilities,including Gekko XII,PHEBUS,Pharos III,and Kanal-2 is described.The many key techniques that are used in the research and development of low-coherence laser drivers are described and analyzed,including low-coherence source generation,amplification,harmonic conversion,and beam smoothing of low-coherence light.Then,recent progress achieved by our group in research on a broadband low-coherence laser driver is presented.During the development of our low-coherence high-power laser facility,we have proposed and implemented many key techniques for working with low-coherence light,including source generation,efficient amplification and propagation,harmonic conversion,beam smoothing,and precise beam control.Based on a series of technological breakthroughs,a kilojoule low-coherence laser driver named Kunwu with a coherence time of only 300 fs has been built,and the first round of physical experiments has been completed.This high-power laser facility provides not only a demonstration and verification platform for key techniques and system integration of a low-coherence laser driver,but also a new type of experimental platform for research into,for example,high-energy-density physics and,in particular,laser–plasma interactions.展开更多
Manganese-based perovskite is popular for research on ferromagnetic materials,and its spectroscopic studies are essential for understanding its electronic structure,dielectric,electrical,and magnetic properties.In thi...Manganese-based perovskite is popular for research on ferromagnetic materials,and its spectroscopic studies are essential for understanding its electronic structure,dielectric,electrical,and magnetic properties.In this paper,the M-edge spectra of La ions and the M-edge,L-edge,and K-edge spectra of Mn ions in LaMnO3 are calculated by considering both the free-ion multiplet calculation and the crystal field effects.We analyze spectral shapes,identify peak origins,and estimate the oxidation states of La and Mn ions in LaMnO3 theoretically.It is concluded that La ions in LaMnO3 predominantly exist in the trivalent state,while Mn ions exist primarily in the trivalent state with a minor presence of tetravalent ions.Furthermore,the calculated spectra are in better conformity with the experimental spectra when the proportion of Mn3+is 90%and Mn4+is 10%.This article enhances our comprehension of the oxidation states of La and Mn within the crystal and also provides a valuable guidance for spectroscopic investigations of other manganates.展开更多
The separation of rare earth elements is particularly difficult due to their similar physicochemical properties.Based on the tiny differences of ionic radius,solvent extraction has been developed as the“mass method”...The separation of rare earth elements is particularly difficult due to their similar physicochemical properties.Based on the tiny differences of ionic radius,solvent extraction has been developed as the“mass method”in industry with hundreds of stages,extremely intensive chemical consumption and large capital investments.The differences of the ionic magnetic moment among rare earths are greater than that of ionic radius.Herein,a novel method based on the large ionic magnetic moment differences of rare earth elements was proposed to promote the separation efficiency.Rare earths were firstly dissolved in the ionic liquid,then the ordering degree of them was improved with the Z-bond effect,and finally the magnetic moment differences between paramagnetic and diamagnetic rare earths in quasi-liquid system were enhanced.Taking the separation of Er/Y,Ho/Y and Er/Ho as examples,the results showed that Er(Ⅲ)and Ho(Ⅲ)containing ionic liquids had obvious magnetic response,while ionic liquids containing Y(Ⅲ)had no response.The separation factors of Er/Y and Ho/Y were achieved at 9.0 and 28.82,respectively.Magnetic separation via quasi-liquid system strategy provides a possibility of the novel,green,and efficient method for rare earth separation.展开更多
The damage characteristics of fused silica were investigated under low-temporal coherence light(LTCL).It was found that the laser-induced damage threshold(LIDT)of fused silica for the LTCL was lower than that of the s...The damage characteristics of fused silica were investigated under low-temporal coherence light(LTCL).It was found that the laser-induced damage threshold(LIDT)of fused silica for the LTCL was lower than that of the single longitudinal mode pulse laser,and for the LTCLs,the LIDTs decrease with the increasing of laser bandwidth,which is not consistent with the temporal spike intensity.This is due to the nonlinear self-focusing effect and multi-pulse accumulation effect.The specific reasons were analyzed based on theoretical simulation and experimental study.This research work is helpful and of great significance for the construction of high-power LTCL devices.展开更多
High gain greater than 106 is crucial for the preamplifiers of joule-class high-energy lasers.In this work,we present a specially designed compact amplifier using 0.5%Nd,5%Gd:SrF_(2)and 0.5%Nd,5%Y:SrF_(2)crystals.The ...High gain greater than 106 is crucial for the preamplifiers of joule-class high-energy lasers.In this work,we present a specially designed compact amplifier using 0.5%Nd,5%Gd:SrF_(2)and 0.5%Nd,5%Y:SrF_(2)crystals.The irregular crystal shape enhances the gain length of the laser beam and helps suppress parasitic oscillations.The amplified spontaneous emission(ASE)induced by the high gain is analyzed through ray tracing.The balance between gain and ASE is estimated via numerical simulation.The gain spectral characteristics of the two-stage two-pass amplifier are examined,demonstrating the advantages of using different crystals,with bandwidths up to 8 nm and gains over 106.In addition,the temperature and stress distributions in the Nd,Gd:SrF_(2)crystal are simulated.This work is expected to contribute to the development of high-peak-power(≥terawatt-class)high-energy(joule-class)laser devices.展开更多
基金Project supported by the National Key R&D Program of China(2017YFE0106900)Science and Technology Major Projects of Fujian Province(2015HZ0001-3)+2 种基金Natural Science Foundation of Fujian Province(2016J05058)Hundreds of Talents ProgramScience and Technology Service Network Initiative from Chinese Academy of Sciences
文摘Methods for transforming rare earth(RE)sulfate into chloride mainly include extraction process with organophosphonic mono-acids or aliphatic acids and precipitation process with ammonium bicarbonate(NH4 HCO3).In this paper,alkylphenoxy carboxylic acids(HAs)ofp-dodecylphenoxy acetic acid(HA-Ⅰ),pdodecylphenoxypropanoic acid(HA-Ⅱ)and p-dodecylphenoxybutyric acid(HA-Ⅲ),which were liquid at room temperature were synthesized and characterized.The precipitation mechanisms of RE elements with the HAs were investigated and the HA/RE molar ratios of the solid complexes were determined as3:1 by equi-molar series method which accord with the principle of charge balance.Applicability of HAs for the transformation of RE sulfate from concentrated sulfuric acid roasted RE concentrate into chloride via precipitation method was discussed.100%HA-Ⅱwas selected as the liquid organic precipitant without dilution of volatile solvent soracceleration of phase separation by phase-modifiers.The RE sulfate solution can be precipitated by HA-Ⅱafter neutralization with liquid NaOH and stripped with concentrated HCl at room temperature.High concentration of RE chloride of 218.1 g/L with low residue of sulfate radical of 0.536 g/L was obtained.The residual organic precipitant in the raffinate solution was tested to be lower than 8 mg/L at 25℃and the chemical oxygen demand(COD)in wastewater was less than 50 mg/L.
基金Project supported by'Hundreds Talents Program' from Chinese Academy of Sciences,Science and Technology Major Project of Fujian Province(2015HZ0001-3)National Natural Science Foundation of China(21571179)Science and Technology Major Project of Ganzhou(2017-8)
文摘A novel purification process based on mixer-settlers for high-purity NdClwas developed. Acidic solution and pure NdClsolution were compared to scrub the less-extractable rare earths(REs)(La, Ce, and Pr)from loaded organic phase. The extractant with low-degree saponification was evaluated to remove the more-extractable element(Sm). Then the RE impurities(La, Ce, Pr, and Sm) in Nd were purified by an integrated process. Furthermore, effect of smuggling behavior on the purification of NdClin mixersettlers was studied. Based on the investigation mentioned above, the pilot-scale purification process for NdClwith a purity of 99.999% was developed, and the total recovery was about 99%.
文摘The use of low-coherence light is expected to be one of the effective ways to suppress or even eliminate the laser–plasma instabilities that arise in attempts to achieve inertial confinement fusion.In this paper,a review of low-coherence high-power laser drivers and related key techniques is first presented.Work at typical low-coherence laser facilities,including Gekko XII,PHEBUS,Pharos III,and Kanal-2 is described.The many key techniques that are used in the research and development of low-coherence laser drivers are described and analyzed,including low-coherence source generation,amplification,harmonic conversion,and beam smoothing of low-coherence light.Then,recent progress achieved by our group in research on a broadband low-coherence laser driver is presented.During the development of our low-coherence high-power laser facility,we have proposed and implemented many key techniques for working with low-coherence light,including source generation,efficient amplification and propagation,harmonic conversion,beam smoothing,and precise beam control.Based on a series of technological breakthroughs,a kilojoule low-coherence laser driver named Kunwu with a coherence time of only 300 fs has been built,and the first round of physical experiments has been completed.This high-power laser facility provides not only a demonstration and verification platform for key techniques and system integration of a low-coherence laser driver,but also a new type of experimental platform for research into,for example,high-energy-density physics and,in particular,laser–plasma interactions.
基金Project supported by the National Natural Science Foundation of China(Grant No.11974253).
文摘Manganese-based perovskite is popular for research on ferromagnetic materials,and its spectroscopic studies are essential for understanding its electronic structure,dielectric,electrical,and magnetic properties.In this paper,the M-edge spectra of La ions and the M-edge,L-edge,and K-edge spectra of Mn ions in LaMnO3 are calculated by considering both the free-ion multiplet calculation and the crystal field effects.We analyze spectral shapes,identify peak origins,and estimate the oxidation states of La and Mn ions in LaMnO3 theoretically.It is concluded that La ions in LaMnO3 predominantly exist in the trivalent state,while Mn ions exist primarily in the trivalent state with a minor presence of tetravalent ions.Furthermore,the calculated spectra are in better conformity with the experimental spectra when the proportion of Mn3+is 90%and Mn4+is 10%.This article enhances our comprehension of the oxidation states of La and Mn within the crystal and also provides a valuable guidance for spectroscopic investigations of other manganates.
基金This research was supported by the National Natural Science Foundation of China(Grant No.22008244)Rare Earth Industry Guidance Fund Project(Grant No.IAGM2020DB03)+1 种基金Self-Deployed Projects of Ganjiang Innovation Academy,Chinese Academy of Sciences(Grant No.E055A002)the Key Research Programof theChinese Academy of Sciences(Grant No.ZDRW-CN-2021-3-2)and Special Research Assistant Project of the Chinese Academy of Sciences.
文摘The separation of rare earth elements is particularly difficult due to their similar physicochemical properties.Based on the tiny differences of ionic radius,solvent extraction has been developed as the“mass method”in industry with hundreds of stages,extremely intensive chemical consumption and large capital investments.The differences of the ionic magnetic moment among rare earths are greater than that of ionic radius.Herein,a novel method based on the large ionic magnetic moment differences of rare earth elements was proposed to promote the separation efficiency.Rare earths were firstly dissolved in the ionic liquid,then the ordering degree of them was improved with the Z-bond effect,and finally the magnetic moment differences between paramagnetic and diamagnetic rare earths in quasi-liquid system were enhanced.Taking the separation of Er/Y,Ho/Y and Er/Ho as examples,the results showed that Er(Ⅲ)and Ho(Ⅲ)containing ionic liquids had obvious magnetic response,while ionic liquids containing Y(Ⅲ)had no response.The separation factors of Er/Y and Ho/Y were achieved at 9.0 and 28.82,respectively.Magnetic separation via quasi-liquid system strategy provides a possibility of the novel,green,and efficient method for rare earth separation.
基金supported by National Natural Science Foundation of China(No.12074353)。
文摘The damage characteristics of fused silica were investigated under low-temporal coherence light(LTCL).It was found that the laser-induced damage threshold(LIDT)of fused silica for the LTCL was lower than that of the single longitudinal mode pulse laser,and for the LTCLs,the LIDTs decrease with the increasing of laser bandwidth,which is not consistent with the temporal spike intensity.This is due to the nonlinear self-focusing effect and multi-pulse accumulation effect.The specific reasons were analyzed based on theoretical simulation and experimental study.This research work is helpful and of great significance for the construction of high-power LTCL devices.
基金supported by the National Major Project of China (Grant No.GFZX020503.10)the National Natural Science Foundation of China (Grant Nos.12074353,62405298 and 61925508)the CAS Project for Young Scientists in Basic Research (Grant No.YSBR-024)
文摘High gain greater than 106 is crucial for the preamplifiers of joule-class high-energy lasers.In this work,we present a specially designed compact amplifier using 0.5%Nd,5%Gd:SrF_(2)and 0.5%Nd,5%Y:SrF_(2)crystals.The irregular crystal shape enhances the gain length of the laser beam and helps suppress parasitic oscillations.The amplified spontaneous emission(ASE)induced by the high gain is analyzed through ray tracing.The balance between gain and ASE is estimated via numerical simulation.The gain spectral characteristics of the two-stage two-pass amplifier are examined,demonstrating the advantages of using different crystals,with bandwidths up to 8 nm and gains over 106.In addition,the temperature and stress distributions in the Nd,Gd:SrF_(2)crystal are simulated.This work is expected to contribute to the development of high-peak-power(≥terawatt-class)high-energy(joule-class)laser devices.
