In 2025,the global rare earth exploration and development sector achieved breakthroughs across multiple fronts.Projects advanced intensively across the Americas,Oceania,Africa,and Europe,with significant growth in res...In 2025,the global rare earth exploration and development sector achieved breakthroughs across multiple fronts.Projects advanced intensively across the Americas,Oceania,Africa,and Europe,with significant growth in resources,continuous emergence of new deposits,and strong impetus injected into the industry by technological innovation and policy support.The global rare earth resource supply pattern was further optimized (Table 1).1.Fruitful results in resource growth and new deposit discoveriesBrazil emerged as a core region for resource growth.The Colossus rare earth deposit saw a 150%increase in resources and announced its first reserve estimate.The Caldeira rare earth deposit’s resource estimate grew by 50%.The combined ore resources in the Caladão rare earth deposit’s Zones A and B reached 5.72×10~8 tonnes,with a total rare earth oxide(TREO) grade of 0.1506%,concurrently hosting 2.29×10~4tonnes of gallium metal resources.展开更多
Rare earth(RE)Y-type zeolite was synthesized in situ by acidic co-hydrolysis route and hydrothermal method.The key process parameters were optimized based on the RE utilization rate.The effect of inducing a rotating p...Rare earth(RE)Y-type zeolite was synthesized in situ by acidic co-hydrolysis route and hydrothermal method.The key process parameters were optimized based on the RE utilization rate.The effect of inducing a rotating packed bed(RPB)in premixing and crystallization on crystallinity and RE utilization rate was further investigated.The results indicate that lanthanide(La)cations are successfully introduced into the sodalite cage of Y-type zeolite.The optimized conditions are that the molar ratio of Si/La is 150,premixing for 5 h,crystallization at 90℃ for 18 h,and calcination at 550℃ for 3.5 h.At this stage,the RE utilization rate reaches 74.5%.Compared with the conventional stirred tank reactor(STR),RPB can effectively shorten the premixing time and crystallization time by 4.3 h and 6 h,improve the crystallinity by 23%and RE utilization rate by 7.5%.The RE utilization rate is more than 80%by RPB,surpassing the effectiveness of using the one-exchange one-calcination process in the traditional liquid ion exchange process.It is expected to provide a reference for the in-situ efficient and green synthesis of RE zeolite.展开更多
As an important strategic rare-earth resource,bastnaesite has long been a global research focus.The carbochlorination process,as an efficient and low-cost extraction method,can be applied to treat bastnaesite,achievin...As an important strategic rare-earth resource,bastnaesite has long been a global research focus.The carbochlorination process,as an efficient and low-cost extraction method,can be applied to treat bastnaesite,achieving ideal rare-earth extraction results in just one-step reaction.By using inexpensive chlorine gas as the chlorinating agent,it avoids lengthy procedural steps and the generation of acid-base waste liquids.Based on this,we propose a novel carbochlorination process for bastnaesite involving a fluorine-fixing agent.Thermodynamic data for the carbochlorination process of bastnaesite were calculated using the group contribution method.Thermodynamic feasibility was verified through Gibbs free energy.The effects of different chlorination times,fluorine-fixing agent dosages,chlorine flow rates,and chlorination temperatures on the carbochlorination process of bastnaesite were investigated.Experimental studies showed that under optimal chlorination conditions,a temperature of 800℃,a duration of 60 min,a fluorine-fixing agent dosage of 10%,and a chlorine flow rate of 10 L·min^(−1),the chlorination rates of rare-earth elements,Ca,Ba,and Fe in bastnaesite reached 96%,99%,98%,and 99%,respectively.The reaction mechanism was explored and analyzed based on characterization results such as mineral phase composition,micromorphology and thermogravimetry of water-washed residues under different chlorination conditions.Additionally,kinetic experiments were conducted at varying reaction temperatures and chlorine flow rates,revealing that the carbon-chlorination process is primarily controlled by chemical reactions.展开更多
Eu^(2+)-doped phosphors show broadband absorption,tunable emission and high quantum efficiency due to the parity-allowed 5d→4f transitions,allowing them to be used in solid-state lighting.To expand their applications...Eu^(2+)-doped phosphors show broadband absorption,tunable emission and high quantum efficiency due to the parity-allowed 5d→4f transitions,allowing them to be used in solid-state lighting.To expand their applications in other fields such as detection and sensing technologies,the Eu^(2+)emission needs to be tuned into the near-infrared region,but it is a big challenge to obtain Eu^(2+)near-infrared region emitters due to the absence of host compounds with extremely large crystal-field splitting.In this work,we chose M_(4)Li(BN_(2))_(3)(M=Ca,Sr,Ba)as a host and realize the near-infrared region emission of Eu^(2+)in it.Among these phosphors,Ba4Li(BN_(2))_(3):Eu^(2+)exhibits the longest emission of 880 nm and the largest full-width at half maximum of 276 nm under 450 nm excitation,while Ca_(4)Li(BN_(2))_(3):Eu^(2+)and Sr_(4)Li(BN_(2))_(3):Eu^(2+)emit at740 and 680 nm,respectively.We observe an interesting phenomenon that the energy shift of emission is linearly related to the radius difference between the alkaline earth cation and the activator Eu^(2+)in this system.展开更多
A novel macroparticle magnesium-modified biochar/yttrium alginate(Mg-BC/SA-Y)hybrid biogel composite was successfully developed through a facile solution reaction of magnesium-modified BC and yttrium alginate polymer,...A novel macroparticle magnesium-modified biochar/yttrium alginate(Mg-BC/SA-Y)hybrid biogel composite was successfully developed through a facile solution reaction of magnesium-modified BC and yttrium alginate polymer,and its properties were characterized.The obtained Mg-BC/SA-Y biogel beads have a particle size of approximately 1.5 mm,featuring abundant network pores and an uneven,distinctive surface.The performance and mechanisms of Mg-BC/SA-Y for phosphate adsorption were thoroughly investigated.The findings indicate that Mg-BC/SA-Y removes up to 95.7%of phosphate at pH4.0 and 298 K,and also achieves a phosphate removal efficiency of over 80%within a pH range of3.0-11.0.The adsorption capacity of Mg-BC/SA-Y for phosphate is nearly four times that of BC.The spontaneous adsorption processes and endothermic adsorption behavior can be elucidated by the pseudo-second-order rate and Langmuir equations,respectively.Phosphate adsorption is almost unaffected by water ionic strength and common coexisting ions,except for the influence of highconcentration F-ions.The recyclable biogel beads can be reused after adsorbing phosphate,and represent excellent stability and practicability in real water.The mechanisms of ligand exchange,innersphere complexation and electrostatic attraction are involved in phosphate removal.Mg-BC/SA-Y biogel polymer is a desirable and sustainable biosorbent for treating water with excessive phosphate levels and reducing pollution and carbon emissions.展开更多
The process of utilizing solar-driven semiconductor water splitting for the production of hydrogen is a vital strategy in the pursuit of a zero-carbon economy.Zn_(0.1)Cd_(0.9)S,a rod-like semiconductor metal sulfide,e...The process of utilizing solar-driven semiconductor water splitting for the production of hydrogen is a vital strategy in the pursuit of a zero-carbon economy.Zn_(0.1)Cd_(0.9)S,a rod-like semiconductor metal sulfide,encounters considerable difficulties stemming from the swift recombination of charge carriers generated by light.Overcoming the coulombic interactions between charge carriers is essential for achieving efficient separation.In this study,we modified Zn_(0.1)Cd_(0.9)S with dodecahedral rare-earth compound CeVO_(4) and employed ultrasonic self-assembly to tightly couple the two materials.This integration established a built-in electric field and constructed an S-scheme heterojunction.Within this configuration,Zn_(0.1)Cd_(0.9)S serves as an electron acceptor while CeVO_(4) functions as an electron donor.Driven by the built-in electric field,electrons rapidly traverse the tightly coupled interface,minimizing their path length.The S-scheme heterojunction preserves the catalyst's strong redox capabilities and facilitates the vectorial separation of photogenerated charge carriers.In situ irradiated X-ray photoelectron spectroscopy(XPS)and electron paramagnetic resonance(EPR)analyses further validated the charge transfer mechanism of the S-scheme heterojunction.Density functional theory calculations elucidated the electronic states and roles of the catalyst,thereby establishing a theoretical framework for the investigation of S-scheme heterojunctions.This work lays a theoretical basis for the design and mechanistic investigation of S-scheme heterojunction catalysts.展开更多
Long-afterglow photocatalytic technology offers promising potential fo r all-weather pollutant treatment,yet its efficiency is often constrained by competition between afterglow emission and photocatalytic reactions.T...Long-afterglow photocatalytic technology offers promising potential fo r all-weather pollutant treatment,yet its efficiency is often constrained by competition between afterglow emission and photocatalytic reactions.To address this,we developed a Pr^(3+)-doped Ca_(2)Al_(2)SiO_(7)(CASO)photocatalyst enriched with oxygen vacancies(V_(O)).The introduction of oxygen vacancies significantly increases trap concentration,enhancing both the intensity and du ration of the afterglow emission.A persulfate-assisted photo-Fenton system was designed based on V_(O)-CASO:Pr^(3+)enabling the self-activated degradation of tetracycline hydrochloride(TC)under ultraviolet afterglow.The photo-Fenton reaction consumes excess holes accumulated during the afterglow process,improving carrier utilization efficiency and mitigating rapid recombination.Additionally,persulfate addition can enrich reactive species and facilitate the Fe^(2+)/Fe^(3+)cycle.Benefiting from these synergistic effects,V_(O)-CASO:Pr^(3+)has achieved 75%TC degradation within1 h,significantly outperforming traditional systems.This study provides a new strategy for enhancing long-afterglow photocatalytic performance,paving the way for sustainable pollutant degradation technologies.展开更多
Although significant progress has been made in the development of red phosphors,the development of efficient and thermally stable red phosphors remains a challenge.In this paper,(Sr_(3-y)Cay)Ca_(1-x)Nb_(2)O_(9):xSm^(3...Although significant progress has been made in the development of red phosphors,the development of efficient and thermally stable red phosphors remains a challenge.In this paper,(Sr_(3-y)Cay)Ca_(1-x)Nb_(2)O_(9):xSm^(3+)phosphors with 648 nm red emission,which belongs to the ^(4)G_(5/2)→^(6)H_(9/2) leap of Sm^(3+)and is close to the absorption wavelengths of plant chloro phylls and photochromes PR,were prepared by the high-temperature solid-phase method.The lattice mismatch between Sm^(3+)and Ca^(2+)is solved by cation substitution,which increases the atomic disorder and lattice distortion,and the lattice distortion also causes the forbidden leap to be disrupted,thus improving the luminescence efficiency.Meanwhile,the substitution of small-radius cations leads to the enhancement of the structural rigidity of the material.The test results show that after the introduction of Ca^(2+),the luminous intensity of the phosphor is increased by 5.15 times,the quantum yield is increased from 22.89%to 48.31%,and the I_(423 K)/I_(298 K) value is increased from 70.7%to 73.4%,and the fluorescence lifetime is also improved accordingly.White light-emitting diodes(WLEDs)and fuchsia light-emitting diodes(LEDs)were successfully prepared using the experimentally prepared phosphors,demonstrating their great potential in the fields of optical thermometers,WLEDs and plant growth.展开更多
Rare earth elements are widely used in steel production due to their unique metallurgical properties,which can modify inclusions,improve the cleanliness of molten steel,and optimize steel properties.However,high activ...Rare earth elements are widely used in steel production due to their unique metallurgical properties,which can modify inclusions,improve the cleanliness of molten steel,and optimize steel properties.However,high activity also makes rare earth elements prone to intense chemical reactions with refractories during the smelting process,which can not only accelerate the erosion and failure of refractories,but also reduce the cleanliness of molten steel owing to the formation of secondary inclusions.Therefore,it is essential to understand the interaction mechanisms between rare earth steels and refractories.Herein,the research progress on the interactions between rare earth steels and refractories is systematically reviewed.Based on both laboratory studies and industrial applications,emphasis is placed on the reaction mechanisms and their effects on the stability of refractories and the cleanliness of molten steel.At the same time,the prevention methods are summarized,including the refractory optimization,protective coatings for nozzles,argon blowing,and the application of external electric fields.Furthermore,the applicability and limitations of these methods are analyzed.Finally,future research directions are discussed to address the limitations of current studies,focusing on the development of novel refractories,non-contact control methods,and digitally intelligent process control.展开更多
Extracting rare earth elements(REEs)from coal refuse is challenging due to their low co ncentrations and poor leachability.Bioleaching has emerged as a sustainable technology to recover REEs from low-grade materials.I...Extracting rare earth elements(REEs)from coal refuse is challenging due to their low co ncentrations and poor leachability.Bioleaching has emerged as a sustainable technology to recover REEs from low-grade materials.In this study,a ferric sulfate bio acid(BA)with an acidity of~0.2 mol/L H^(+),generated through regulated pyrite bio-oxidation,was used to leach REEs and critical metals(CMs)from coal refuse(ground to<1 mm)after 20-min roasting at 600℃.The influences of solid/liquid(S/L)ratio(100-300 g/L)and leaching temperature(25-95℃)on the leaching performance were examined.The leaching mechanisms were investigated by conducting stepwise precipitation tests and spectroscopic characterization.Results show that raising the leaching temperature to≥65℃accelerated the REE leaching kinetics but causes the loss of light REEs(LREEs)after reaching peak values at 30-60 min.Stage precipitation tests reveal that the loss is due to the incorporation of REEs,especially for LREEs,by gypsum and schwertmannite.The peak total REE(TREE)recovery of the BA leaching reaches 24.9%after 30 min of leaching at75℃with a S/L ratio of 200 g/L.Implementing the three-stage counter-current leaching increases the overall TREE recovery to 31.8%by recovering the REEs incorporated in the Fe and Ca precipitates.Meanwhile,promising recovery values of Li(55.5%),Mn(74.6%),Ni(41.6%),and Co(35.3%)are also achieved.This method provides a sustainable approach to extract REEs and critical metals from coal waste materials with a high treatment capacity.展开更多
Genetic hypoparathyroidism(HP),achondroplasia(ACH),and primary growth hormone deficiency(GHD)are listed as rare diseases in the second List of Rare Diseases in China in 2023.Numerous studies have explored optimal ther...Genetic hypoparathyroidism(HP),achondroplasia(ACH),and primary growth hormone deficiency(GHD)are listed as rare diseases in the second List of Rare Diseases in China in 2023.Numerous studies have explored optimal therapies for certain rare endocrine diseases,and the development of long-acting therapeutic agents has been considered a key strategy for improving treatment outcomes,especially given the challenges associated with daily subcutaneous injections.However,limited attention has been given to the potential of"transient conjugation"(TransCon)technology,a platform designed to convert drugs into prodrug forms,thereby extending their half-lives and reducing dosing frequency,which demonstrates promise as a more convenient treatment option for these conditions.This is the first study to review the research progress of TransCon technology in the treatment of HP,ACH,and GHD,focusing on its pharmacokinetic properties,efficacy,safety,tolerability,and patient-reported outcomes in comparison with conventional therapies,in order to provide a reference for formulation development and clinical management of these rare endocrine diseases.展开更多
Phosphorus (P) is an essential nutrient element that is critical for plant growth and ecosystem functionality.The soil P cycle plays multiple roles,such as sustaining plant growth and productivity,regulating nutrient ...Phosphorus (P) is an essential nutrient element that is critical for plant growth and ecosystem functionality.The soil P cycle plays multiple roles,such as sustaining plant growth and productivity,regulating nutrient balance within ecosystems,and enhancing ecosystem adaptability and resilience.This cycle is influenced by factors such as the restoration approach and microbial community dynamics.However,the extent to which the restoration approach alters the P cycle in karst ecosystems and the underlying microbial mechanisms remain poorly understood.The P-cycle multifunctionality index (P-cycle MFI) serves as a comprehensive indicator for evaluating soil P cycle function,and it provides insights into changes in the P cycle between different restoration approaches.To investigate the shifts in soil P-cycle MFI and microbial mechanisms between different restoration approaches,we analyzed soil available P (AP),total P (TP),microbial biomass P (MBP),and the activities of acid phosphatase (ACP) and alkaline phosphatase (ALP).These data were used to calculate the P-cycle MFI by averaging the Z-scores between two restoration approaches(artificial restoration of forest (AF) and natural restoration of forest (NF)) and a control (cropland,CP) at six subtropical karst ecosystem sites in China.We also determined the soil organic carbon (SOC),exchangeable calcium (Ca) and magnesium (Mg),pH,bulk density (BD),microbial biomass C (MBC),and microbial biomass nitrogen (MBN),as well as the community structure,relative abundance,diversity indices,and co-occurrence networks of phoD-harboring bacteria.The results showed that the community structure of phoD-harboring bacteria varied significantly among AF,NF,and CP and across different temperature gradients.These bacteria exhibited increasing complexity and tightness in co-occurrence networks from CP to AF and then to NF,along with the ACP and ALP activities,but not the TP and AP contents.The P-cycle MFI values were significantly higher in NF compared to AF and CP,and the variation was significantly explained by restoration approach,temperature,MBC,MBN,SOC,exchangeable Ca,BD,community structure of phoD-harboring bacteria,and exchangeable Mg.Furthermore,natural restoration had a more substantial impact on the P-cycle MFI than temperature by enhancing SOC,microbial biomass,the complexity and co-occurrence network tightness of the phoD-harboring bacterial community structure,and ACP and ALP activities,but it reduced soil BD.The rare genera of phoD-harboring bacteria significantly influenced the variation of soil P-cycle MFI compared to the dominant genera.This study highlights the importance of rare genera of phoD-harboring bacteria in driving soil P-cycle multifunctionality in karst ecosystems,with natural restoration being more effective than artificial methods for enhancing soil organic matter and microbial community complexity.展开更多
This research presents a detailed ab initio density functional theory(DFT)analysis on magnetic,thermoelectric,and optoelectronic properties of CaPr_(2)(S/Se)_(4) executed by Wien2k and Boltztrap2 packages for spintron...This research presents a detailed ab initio density functional theory(DFT)analysis on magnetic,thermoelectric,and optoelectronic properties of CaPr_(2)(S/Se)_(4) executed by Wien2k and Boltztrap2 packages for spintronic energy applications.The density of states,optimization energy,and negative formation energy all support the stability of the ferromagnetic state.The spin polarization density and Curie temperature(310 and 289 K)are also reported.In addition,the double exchange model,hybridization,density of states,band structures,exchange constants,exchange energies,and crystal field energies are addressed to ensure ferromagnetism by the spin of electrons.The magnetic moment of Pr shifts to Ca and S/Se sites,revealing that ferromagnetism is due to electron spin,not clustering of Pr magnetic ions.Thermoelectrics were evaluated by electrical conductivity(σ),thermal conductivity(k_(e)),Seebeck coefficient(S),power factor(S^(2)),and figures of merit(ZT).The room tempe rature values of S(0.169,0.183 mV/K)and ZT(0.76,0.90)increase their thermoelectric performance.Furthermore,dielectric function,refractive index,absorption coefficientα(ω),reflectivity R(ω),and other parameters are demonstrated in detail.Therefore,researchers can develop materials with the potential for spintronic and energy harvesting.展开更多
Cyclic olefin copolymers(COCs)are highly valuable optical resins,but their productions on industry are fully limited by the monomer norbornene.Although ethylene/dicyclopentadiene(E/DCPD)copolymers provide a cost-effec...Cyclic olefin copolymers(COCs)are highly valuable optical resins,but their productions on industry are fully limited by the monomer norbornene.Although ethylene/dicyclopentadiene(E/DCPD)copolymers provide a cost-effective alternative to commercially available COCs because of using low-cost DCPD as cyclic olefin monomer,these inherent unsaturated double bonds on E/DCPD copolymers cause low heat resistance,oxidation,and crosslinking during processing and storage.And E/DCPD copolymers usually showed lower glass-transition temperature(T_(g))compared with commercially available COCs.In this study,we studied the E-DCPD copolymerization catalyzed by a scandium complex and the sequential hydrogenation catalyzed by a nickel compound to prepare saturated copolymers H-(E/DCPD).The polymerization activities are high up to 5.86×10^(6)g/(molSc·h),and the resultant H-(E/DCPD)copolymers showed narrow polymer dispersity index(PDI=1.5–2.0).By changing the polymerization conditions,a series of H-(E/DCPD)copolymers with tunable DCPD incorporation(28.4 mol%–44.9 mol%)and a wide range of T_(g)(123–171°C)were obtained.H-(E/DCPD)copolymers exhibited excellent optical properties(transparency>90%,refractive index of 1.543),similar to those of commercial COCs,making them an alternative for high-performance optical applications.This method solves the problems of traditional E/DCPD copolymers and provides a practical way to produce stable and low-cost COCs,and is comparable with commercially available COC resins.展开更多
Ln@MOFs by anchoring rare metal ions(Ln) into metal-organic frameworks(MOFs) are proved to have great potential in the field of luminescent molecular thermometer.Nevertheless,the current research indicated that the po...Ln@MOFs by anchoring rare metal ions(Ln) into metal-organic frameworks(MOFs) are proved to have great potential in the field of luminescent molecular thermometer.Nevertheless,the current research indicated that the poor structural stability and low sensitivity hindered their application scope.In this work,a new MOF Zn-450 luminescent thermometer with multiple emission fluorescence characteristics was synthesized by the combination of 3,3,5,5-biphenyl tetracarboxylic acid(H_(4)L) and Zn^(2+) ion under solvothermal conditions.Interestingly,a high relative sensitivity of 1.43 % K^(-1) was found within 80-300 K based on Zn-450.Subsequently,two high-sensitivity luminescent Ln@MOFs(Ln = Eu and Tb) were further fabricated by doping rare earth ions into Zn-450 based on the post-synthesis strategy.Among them,the Eu@Zn-450 demonstrates various luminous behaviors while achieving an increased relative sensitivity of 1.63 % K^(-1).In addition,the continuously visible red,pink,and purple luminescent emissions at the same temperature range were observed,suggesting that the Eu@Zn-450 could be utilized as a luminescent colorimetric molecular thermometer.Importantly,this work can present new possibilities for the development of rare earth-doped luminescence and its temperature sensing properties.展开更多
Understanding the underlying mechanism that enhances the separation of specific target ions from complex background aqueous solutions is crucial for achieving controllable chemical reactions and industrial purificatio...Understanding the underlying mechanism that enhances the separation of specific target ions from complex background aqueous solutions is crucial for achieving controllable chemical reactions and industrial purification processes in modern industries.This study investigated the enhanced kinetic separatio n of target metal ions from complex aqueous solutio ns at a liquid-liquid interface,focusing on the presence of coexisting salt cations.Employing a typical thin-layer organic oil film(TOOF)extraction as a model system,the research examines how background Al^(3+)ions influence the mass transfer and separation of ions.Notably,the co ncentration of Al^(3+)ions affects both the distribution of Er^(3+)ions at the oil-water interface and the arrangement and orientation of P507 extractant molecules through the formation of unique hydrogen-bonding interactions.These interactions influence the selectivity of mass transfer,facilitating the separation of Er^(3+)from Al^(3+)ions.Specifically,the hydration shell of Er^(3+)ions is disrupted due to the strong hydration capability of coexisting Al^(3+)ions,leading to a higher interfacial concentration of Er^(3+)ions and a more ordered interfacial orientation of P507 molecules.At lower concentrations of Al^(3+)ions,the diffusion rate of Er^(3+)ions near the interface is high,enhancing the sepa ration perfo rmance of these ions.In contrast,at higher concentrations of Al^(3+)ions,the competitive hydration by Al^(3+)ions increases,and the interfacial concentration of Er^(3+)ions decreases due to enhanced diffusion resistance,resulting in poorer separation performance.Furthermore,a thinner membrane is more effective than a thicker one in enriching target Er^(3+)ions at the interface and achieving an ordered interfacial orientation of P507 molecules,thereby enhancing the separation coefficient(β_(Er/Al)).This work provides novel insights into the behaviors of ions and extractants at oil-wate r interface and the kinetic separation selectivity under varying concentrations of coexisting salt cations.展开更多
Bayan Obo rare earth mine is the largest light rare earth resource worldwide,primarily extracts rare earth elements(REEs)from mixed RE concentrates with bastnaesite and monazite.Nevertheless,the adoption of the concen...Bayan Obo rare earth mine is the largest light rare earth resource worldwide,primarily extracts rare earth elements(REEs)from mixed RE concentrates with bastnaesite and monazite.Nevertheless,the adoption of the concentrated sulfuric acid roasting metallurgical process has resulted in damage to the environment.Therefore,this paper adopted the method of selective mineral phase transformation(MPT)followed by enhanced micro-flotation.By determining the optimal MPT co nditions,the flotation recovery of bastnaesite-roasted products by the collector(phthalic acid,PA)is improved,and the enhanced separation of bastnaesite with monazite is realized.The results show that with the increase of roasting temperature and time,the bastnaesite decomposition product is CeOF and monazite does not change significantly.Subsequent micro-flotation exhibits a gradual decline in the PA consumption of bastnaesiteroasted products,while the flotation recovery of monazite-roasted products remains poor.The artificial mixed ore experiments result in a CeOF foam product with a content of 94.14%and a recovery of 85.80%,and a monazite tank product with a content of 73.53%and a recovery of 87.87%.Compared with the preroasting ore,the surface and interior of bastnaesite-roasted products develop numerous cracks and porosities,and no obvious structural damage is observed in monazite-roasted particles.As the roasting temperature increases,the mineral particles undergo recrystallization or closure,reducing the specific surface area of bastnaesite-roasted products and enhancing hydrophobicity,leading to diminished PA consumption.Fourier transform infrared and other flotation-relation tests show that PA is chemisorbed on the surface of CeOF.The MPT conditions are optimized in this study,which provides a reference for further advancing the efficient separation of bastnaesite and monazite.展开更多
The efficient flotation separation of rare earth elements(REEs)from gangue minerals is crucial in mineral processing.This study synthesized a quaternary ammonium salt ionic liquid collector,tetrabutylammonium salicylh...The efficient flotation separation of rare earth elements(REEs)from gangue minerals is crucial in mineral processing.This study synthesized a quaternary ammonium salt ionic liquid collector,tetrabutylammonium salicylhydroxamate(T-S),and investigated its performance in separating bastnaesite and fluorite.T-S was synthesized from salicylhydroxamic acid(SHA)and tetrabutylammonium chloride(TBAC),and its molecular structure was characterized using Fourier transform infrared(FTIR)spectroscopy.Microflotation tests indicate that T-S outperforms SHA and TBAC in both collecting ability and selectivity for bastnaesite.Adsorption,zeta potential,and infrared spectroscopy measurements reveal that T-S exhibits stronger adsorption on bastnaesite compared to SHA and TBAC.X-ray photoelectron spectroscopy(XPS)and molecular dynamics simulations(MDS)results confirm that chemical adsorption occurs between Ce on the bastnaesite surface and the-C(=O)NHOH groups of T-S.Moreover,the interaction between T-S and the bastnaesite surface is stronger than that with the fluorite surface.This work provides valuable insights for designing ionic liquid collectors for the flotation separation of bastnaesite and fluorite.展开更多
The occurrence of severe thalassemia,an inherited blood disorder that is either blood-transfusiondependent or fatal,can be mitigated through carrier screening.Here,we aim to evaluate the effectiveness and outcomes of ...The occurrence of severe thalassemia,an inherited blood disorder that is either blood-transfusiondependent or fatal,can be mitigated through carrier screening.Here,we aim to evaluate the effectiveness and outcomes of pre-conceptional and early pregnancy screening initiatives for severe thalassemia prevention in a diverse population of 28,043 women.Using next-generation sequencing(NGS),we identify 4,226(15.07%)thalassemia carriers across 29 ethnic groups and categorize them into high-(0.75%),low-(25.86%),and unknown-risk(69.19%)groups based on their spouses'screening results.Post-screening follow-up reveals 59 fetuses with severe thalassemia exclusively in high-risk couples,underscoring the efficacy of risk classification.Among 25,053 live births over 6 months of age,two severe thalassemia infants were born to unknown-risk couples,which was attributed to incomplete screening and late NGS-based testing for a rare variant.Notably,64 rare variants are identified in 287 individuals,highlighting the genetic heterogeneity of thalassemia.We also observe that migrant flow significantly impacts carrier rates,with 93.90%of migrants to Chenzhou originating from high-prevalence regions in southern China.Our study demonstrates that NGS-based screening during pre-conception and early pregnancy is effective for severe thalassemia prevention,emphasizing the need for continuous screening efforts in areas with high and underestimated prevalence.展开更多
The optimization of microstructure represents a significant methodology for enhancing coercivity(Hcj).This paper concentrates on optimizing the microstructure of magnets through the manipulation of the composition of ...The optimization of microstructure represents a significant methodology for enhancing coercivity(Hcj).This paper concentrates on optimizing the microstructure of magnets through the manipulation of the composition of low-melting-point and high-melting-point elements,thereby achieving the objective of augmenting the comprehensive magnetic properties of magnets.The present study is concerned with the microstructure of magnets comprising three distinct Ga and B contents,and the associated changes in their magnetic properties.The findings indicate that when the Ga content is 0.5 wt%and the B content is 0.88 wt%,the coercivity of the magnets is markedly enhanced.This is evidenced by an increase in coercivity from 8.51 to 14.83 kOe,representing a 74.26%rise.Concurrently,the residual magnetization strength of the magnet remains unaltered.This finding provides a crucial foundation for optimizing the overall magnetic properties of the magnets.The microstructural analysis indicates that a reduction in B content coupled with an increase in Ga content leads to the melting of sharp angles on the surface of the main-phase grains,facilitated by low-melting-point rare-earth-rich phases.This process results in the migration of Fe from the grain boundaries(GBs)to the triple junction phases(TJPs),while Nd migrates from the TJPs to the GBs.This migration results in a reduction in the agglomeration of rare-earth-rich elements within the TJPs,thereby increasing the Nd content in the GBs.This increase enhances the wettability of the GBs,while the reduction of Fe content in this phase mitigates the exchange-coupling effect between the main-phase GBs.Consequently,the GBs become more smooth,more homogeneous and more continuous,which ultimately results in an enhancement of the coercivity of the magnets.展开更多
文摘In 2025,the global rare earth exploration and development sector achieved breakthroughs across multiple fronts.Projects advanced intensively across the Americas,Oceania,Africa,and Europe,with significant growth in resources,continuous emergence of new deposits,and strong impetus injected into the industry by technological innovation and policy support.The global rare earth resource supply pattern was further optimized (Table 1).1.Fruitful results in resource growth and new deposit discoveriesBrazil emerged as a core region for resource growth.The Colossus rare earth deposit saw a 150%increase in resources and announced its first reserve estimate.The Caldeira rare earth deposit’s resource estimate grew by 50%.The combined ore resources in the Caladão rare earth deposit’s Zones A and B reached 5.72×10~8 tonnes,with a total rare earth oxide(TREO) grade of 0.1506%,concurrently hosting 2.29×10~4tonnes of gallium metal resources.
基金supported by the NationalKey Research and Development Program of China(2023YFA1507701)National Natural Science Foundation of China(U22B6011,22288102)“Announcement and Challenge”Science and Technology Project of Xinjiang Uygur Autonomous Region(XJKJTJBGS-2023).
文摘Rare earth(RE)Y-type zeolite was synthesized in situ by acidic co-hydrolysis route and hydrothermal method.The key process parameters were optimized based on the RE utilization rate.The effect of inducing a rotating packed bed(RPB)in premixing and crystallization on crystallinity and RE utilization rate was further investigated.The results indicate that lanthanide(La)cations are successfully introduced into the sodalite cage of Y-type zeolite.The optimized conditions are that the molar ratio of Si/La is 150,premixing for 5 h,crystallization at 90℃ for 18 h,and calcination at 550℃ for 3.5 h.At this stage,the RE utilization rate reaches 74.5%.Compared with the conventional stirred tank reactor(STR),RPB can effectively shorten the premixing time and crystallization time by 4.3 h and 6 h,improve the crystallinity by 23%and RE utilization rate by 7.5%.The RE utilization rate is more than 80%by RPB,surpassing the effectiveness of using the one-exchange one-calcination process in the traditional liquid ion exchange process.It is expected to provide a reference for the in-situ efficient and green synthesis of RE zeolite.
基金supported by the National Natural Science Foundation of China(ZX20230386)the 2023 Special Project for High-Industrial Base Reconstruction Quality Development of the Manufacturing Industry(2023ZY01019-11)the sixth batch of top talent support funds(QNBJ-2022-04).
文摘As an important strategic rare-earth resource,bastnaesite has long been a global research focus.The carbochlorination process,as an efficient and low-cost extraction method,can be applied to treat bastnaesite,achieving ideal rare-earth extraction results in just one-step reaction.By using inexpensive chlorine gas as the chlorinating agent,it avoids lengthy procedural steps and the generation of acid-base waste liquids.Based on this,we propose a novel carbochlorination process for bastnaesite involving a fluorine-fixing agent.Thermodynamic data for the carbochlorination process of bastnaesite were calculated using the group contribution method.Thermodynamic feasibility was verified through Gibbs free energy.The effects of different chlorination times,fluorine-fixing agent dosages,chlorine flow rates,and chlorination temperatures on the carbochlorination process of bastnaesite were investigated.Experimental studies showed that under optimal chlorination conditions,a temperature of 800℃,a duration of 60 min,a fluorine-fixing agent dosage of 10%,and a chlorine flow rate of 10 L·min^(−1),the chlorination rates of rare-earth elements,Ca,Ba,and Fe in bastnaesite reached 96%,99%,98%,and 99%,respectively.The reaction mechanism was explored and analyzed based on characterization results such as mineral phase composition,micromorphology and thermogravimetry of water-washed residues under different chlorination conditions.Additionally,kinetic experiments were conducted at varying reaction temperatures and chlorine flow rates,revealing that the carbon-chlorination process is primarily controlled by chemical reactions.
基金Project supported by the National Key Research and Development Program(2022YFE0108800)。
文摘Eu^(2+)-doped phosphors show broadband absorption,tunable emission and high quantum efficiency due to the parity-allowed 5d→4f transitions,allowing them to be used in solid-state lighting.To expand their applications in other fields such as detection and sensing technologies,the Eu^(2+)emission needs to be tuned into the near-infrared region,but it is a big challenge to obtain Eu^(2+)near-infrared region emitters due to the absence of host compounds with extremely large crystal-field splitting.In this work,we chose M_(4)Li(BN_(2))_(3)(M=Ca,Sr,Ba)as a host and realize the near-infrared region emission of Eu^(2+)in it.Among these phosphors,Ba4Li(BN_(2))_(3):Eu^(2+)exhibits the longest emission of 880 nm and the largest full-width at half maximum of 276 nm under 450 nm excitation,while Ca_(4)Li(BN_(2))_(3):Eu^(2+)and Sr_(4)Li(BN_(2))_(3):Eu^(2+)emit at740 and 680 nm,respectively.We observe an interesting phenomenon that the energy shift of emission is linearly related to the radius difference between the alkaline earth cation and the activator Eu^(2+)in this system.
基金Project supported by the National Natural Science Foundation of China(21167011)the Natural Science Foundation of Inner Mongolia Autonomous Region,China(2020LH02009)the Collaborative Innovation Center for Water Environment Security of Inner Mongolia Autonomous Region,China(XTCX003)。
文摘A novel macroparticle magnesium-modified biochar/yttrium alginate(Mg-BC/SA-Y)hybrid biogel composite was successfully developed through a facile solution reaction of magnesium-modified BC and yttrium alginate polymer,and its properties were characterized.The obtained Mg-BC/SA-Y biogel beads have a particle size of approximately 1.5 mm,featuring abundant network pores and an uneven,distinctive surface.The performance and mechanisms of Mg-BC/SA-Y for phosphate adsorption were thoroughly investigated.The findings indicate that Mg-BC/SA-Y removes up to 95.7%of phosphate at pH4.0 and 298 K,and also achieves a phosphate removal efficiency of over 80%within a pH range of3.0-11.0.The adsorption capacity of Mg-BC/SA-Y for phosphate is nearly four times that of BC.The spontaneous adsorption processes and endothermic adsorption behavior can be elucidated by the pseudo-second-order rate and Langmuir equations,respectively.Phosphate adsorption is almost unaffected by water ionic strength and common coexisting ions,except for the influence of highconcentration F-ions.The recyclable biogel beads can be reused after adsorbing phosphate,and represent excellent stability and practicability in real water.The mechanisms of ligand exchange,innersphere complexation and electrostatic attraction are involved in phosphate removal.Mg-BC/SA-Y biogel polymer is a desirable and sustainable biosorbent for treating water with excessive phosphate levels and reducing pollution and carbon emissions.
基金Project supported by the National Natural Science Foundation of China(22271106,52073286)the Natural Science Foundation of Fujian Province(2006L2005)。
文摘The process of utilizing solar-driven semiconductor water splitting for the production of hydrogen is a vital strategy in the pursuit of a zero-carbon economy.Zn_(0.1)Cd_(0.9)S,a rod-like semiconductor metal sulfide,encounters considerable difficulties stemming from the swift recombination of charge carriers generated by light.Overcoming the coulombic interactions between charge carriers is essential for achieving efficient separation.In this study,we modified Zn_(0.1)Cd_(0.9)S with dodecahedral rare-earth compound CeVO_(4) and employed ultrasonic self-assembly to tightly couple the two materials.This integration established a built-in electric field and constructed an S-scheme heterojunction.Within this configuration,Zn_(0.1)Cd_(0.9)S serves as an electron acceptor while CeVO_(4) functions as an electron donor.Driven by the built-in electric field,electrons rapidly traverse the tightly coupled interface,minimizing their path length.The S-scheme heterojunction preserves the catalyst's strong redox capabilities and facilitates the vectorial separation of photogenerated charge carriers.In situ irradiated X-ray photoelectron spectroscopy(XPS)and electron paramagnetic resonance(EPR)analyses further validated the charge transfer mechanism of the S-scheme heterojunction.Density functional theory calculations elucidated the electronic states and roles of the catalyst,thereby establishing a theoretical framework for the investigation of S-scheme heterojunctions.This work lays a theoretical basis for the design and mechanistic investigation of S-scheme heterojunction catalysts.
基金Project supported by the National Natural Science Foundation of China(12374181)Fundamental Research Funds for Public Universities in Liaoning(LJ212410140035,LJ212410140037,LJ212410140048)+2 种基金Shenyang Science and Technology Bureau(22-315-6-06)General Project of the Department of Education of Liaoning Province(LJKZ0084)Liaoning Province Science and Technology Plan Joint Program(Natural Science Foundation General Project,2024-MSLH-188)。
文摘Long-afterglow photocatalytic technology offers promising potential fo r all-weather pollutant treatment,yet its efficiency is often constrained by competition between afterglow emission and photocatalytic reactions.To address this,we developed a Pr^(3+)-doped Ca_(2)Al_(2)SiO_(7)(CASO)photocatalyst enriched with oxygen vacancies(V_(O)).The introduction of oxygen vacancies significantly increases trap concentration,enhancing both the intensity and du ration of the afterglow emission.A persulfate-assisted photo-Fenton system was designed based on V_(O)-CASO:Pr^(3+)enabling the self-activated degradation of tetracycline hydrochloride(TC)under ultraviolet afterglow.The photo-Fenton reaction consumes excess holes accumulated during the afterglow process,improving carrier utilization efficiency and mitigating rapid recombination.Additionally,persulfate addition can enrich reactive species and facilitate the Fe^(2+)/Fe^(3+)cycle.Benefiting from these synergistic effects,V_(O)-CASO:Pr^(3+)has achieved 75%TC degradation within1 h,significantly outperforming traditional systems.This study provides a new strategy for enhancing long-afterglow photocatalytic performance,paving the way for sustainable pollutant degradation technologies.
基金Project supported by the National Natural Science Foundation of China(52403403)Guizhou Provincial Basic Research Program(Natural Science)(Qian ke he ji chu-ZK 20242024 YiBan 095)。
文摘Although significant progress has been made in the development of red phosphors,the development of efficient and thermally stable red phosphors remains a challenge.In this paper,(Sr_(3-y)Cay)Ca_(1-x)Nb_(2)O_(9):xSm^(3+)phosphors with 648 nm red emission,which belongs to the ^(4)G_(5/2)→^(6)H_(9/2) leap of Sm^(3+)and is close to the absorption wavelengths of plant chloro phylls and photochromes PR,were prepared by the high-temperature solid-phase method.The lattice mismatch between Sm^(3+)and Ca^(2+)is solved by cation substitution,which increases the atomic disorder and lattice distortion,and the lattice distortion also causes the forbidden leap to be disrupted,thus improving the luminescence efficiency.Meanwhile,the substitution of small-radius cations leads to the enhancement of the structural rigidity of the material.The test results show that after the introduction of Ca^(2+),the luminous intensity of the phosphor is increased by 5.15 times,the quantum yield is increased from 22.89%to 48.31%,and the I_(423 K)/I_(298 K) value is increased from 70.7%to 73.4%,and the fluorescence lifetime is also improved accordingly.White light-emitting diodes(WLEDs)and fuchsia light-emitting diodes(LEDs)were successfully prepared using the experimentally prepared phosphors,demonstrating their great potential in the fields of optical thermometers,WLEDs and plant growth.
基金supported by the National Natural Science Foundation of China(Nos.52450003,52025041,U2341267,and 52174294).
文摘Rare earth elements are widely used in steel production due to their unique metallurgical properties,which can modify inclusions,improve the cleanliness of molten steel,and optimize steel properties.However,high activity also makes rare earth elements prone to intense chemical reactions with refractories during the smelting process,which can not only accelerate the erosion and failure of refractories,but also reduce the cleanliness of molten steel owing to the formation of secondary inclusions.Therefore,it is essential to understand the interaction mechanisms between rare earth steels and refractories.Herein,the research progress on the interactions between rare earth steels and refractories is systematically reviewed.Based on both laboratory studies and industrial applications,emphasis is placed on the reaction mechanisms and their effects on the stability of refractories and the cleanliness of molten steel.At the same time,the prevention methods are summarized,including the refractory optimization,protective coatings for nozzles,argon blowing,and the application of external electric fields.Furthermore,the applicability and limitations of these methods are analyzed.Finally,future research directions are discussed to address the limitations of current studies,focusing on the development of novel refractories,non-contact control methods,and digitally intelligent process control.
文摘Extracting rare earth elements(REEs)from coal refuse is challenging due to their low co ncentrations and poor leachability.Bioleaching has emerged as a sustainable technology to recover REEs from low-grade materials.In this study,a ferric sulfate bio acid(BA)with an acidity of~0.2 mol/L H^(+),generated through regulated pyrite bio-oxidation,was used to leach REEs and critical metals(CMs)from coal refuse(ground to<1 mm)after 20-min roasting at 600℃.The influences of solid/liquid(S/L)ratio(100-300 g/L)and leaching temperature(25-95℃)on the leaching performance were examined.The leaching mechanisms were investigated by conducting stepwise precipitation tests and spectroscopic characterization.Results show that raising the leaching temperature to≥65℃accelerated the REE leaching kinetics but causes the loss of light REEs(LREEs)after reaching peak values at 30-60 min.Stage precipitation tests reveal that the loss is due to the incorporation of REEs,especially for LREEs,by gypsum and schwertmannite.The peak total REE(TREE)recovery of the BA leaching reaches 24.9%after 30 min of leaching at75℃with a S/L ratio of 200 g/L.Implementing the three-stage counter-current leaching increases the overall TREE recovery to 31.8%by recovering the REEs incorporated in the Fe and Ca precipitates.Meanwhile,promising recovery values of Li(55.5%),Mn(74.6%),Ni(41.6%),and Co(35.3%)are also achieved.This method provides a sustainable approach to extract REEs and critical metals from coal waste materials with a high treatment capacity.
文摘Genetic hypoparathyroidism(HP),achondroplasia(ACH),and primary growth hormone deficiency(GHD)are listed as rare diseases in the second List of Rare Diseases in China in 2023.Numerous studies have explored optimal therapies for certain rare endocrine diseases,and the development of long-acting therapeutic agents has been considered a key strategy for improving treatment outcomes,especially given the challenges associated with daily subcutaneous injections.However,limited attention has been given to the potential of"transient conjugation"(TransCon)technology,a platform designed to convert drugs into prodrug forms,thereby extending their half-lives and reducing dosing frequency,which demonstrates promise as a more convenient treatment option for these conditions.This is the first study to review the research progress of TransCon technology in the treatment of HP,ACH,and GHD,focusing on its pharmacokinetic properties,efficacy,safety,tolerability,and patient-reported outcomes in comparison with conventional therapies,in order to provide a reference for formulation development and clinical management of these rare endocrine diseases.
基金supported by the National Key Research and Development Program of China (2022YFF1300705)the Key Research and Development Project of Guangxi,China (Guike AB24010051)+1 种基金the National Natural Science Foundation of China (42261011,32271730 and U20A2011)the Central Public Welfare Research Institutes,Chinese Academy of Geological Sciences (2023020)。
文摘Phosphorus (P) is an essential nutrient element that is critical for plant growth and ecosystem functionality.The soil P cycle plays multiple roles,such as sustaining plant growth and productivity,regulating nutrient balance within ecosystems,and enhancing ecosystem adaptability and resilience.This cycle is influenced by factors such as the restoration approach and microbial community dynamics.However,the extent to which the restoration approach alters the P cycle in karst ecosystems and the underlying microbial mechanisms remain poorly understood.The P-cycle multifunctionality index (P-cycle MFI) serves as a comprehensive indicator for evaluating soil P cycle function,and it provides insights into changes in the P cycle between different restoration approaches.To investigate the shifts in soil P-cycle MFI and microbial mechanisms between different restoration approaches,we analyzed soil available P (AP),total P (TP),microbial biomass P (MBP),and the activities of acid phosphatase (ACP) and alkaline phosphatase (ALP).These data were used to calculate the P-cycle MFI by averaging the Z-scores between two restoration approaches(artificial restoration of forest (AF) and natural restoration of forest (NF)) and a control (cropland,CP) at six subtropical karst ecosystem sites in China.We also determined the soil organic carbon (SOC),exchangeable calcium (Ca) and magnesium (Mg),pH,bulk density (BD),microbial biomass C (MBC),and microbial biomass nitrogen (MBN),as well as the community structure,relative abundance,diversity indices,and co-occurrence networks of phoD-harboring bacteria.The results showed that the community structure of phoD-harboring bacteria varied significantly among AF,NF,and CP and across different temperature gradients.These bacteria exhibited increasing complexity and tightness in co-occurrence networks from CP to AF and then to NF,along with the ACP and ALP activities,but not the TP and AP contents.The P-cycle MFI values were significantly higher in NF compared to AF and CP,and the variation was significantly explained by restoration approach,temperature,MBC,MBN,SOC,exchangeable Ca,BD,community structure of phoD-harboring bacteria,and exchangeable Mg.Furthermore,natural restoration had a more substantial impact on the P-cycle MFI than temperature by enhancing SOC,microbial biomass,the complexity and co-occurrence network tightness of the phoD-harboring bacterial community structure,and ACP and ALP activities,but it reduced soil BD.The rare genera of phoD-harboring bacteria significantly influenced the variation of soil P-cycle MFI compared to the dominant genera.This study highlights the importance of rare genera of phoD-harboring bacteria in driving soil P-cycle multifunctionality in karst ecosystems,with natural restoration being more effective than artificial methods for enhancing soil organic matter and microbial community complexity.
文摘This research presents a detailed ab initio density functional theory(DFT)analysis on magnetic,thermoelectric,and optoelectronic properties of CaPr_(2)(S/Se)_(4) executed by Wien2k and Boltztrap2 packages for spintronic energy applications.The density of states,optimization energy,and negative formation energy all support the stability of the ferromagnetic state.The spin polarization density and Curie temperature(310 and 289 K)are also reported.In addition,the double exchange model,hybridization,density of states,band structures,exchange constants,exchange energies,and crystal field energies are addressed to ensure ferromagnetism by the spin of electrons.The magnetic moment of Pr shifts to Ca and S/Se sites,revealing that ferromagnetism is due to electron spin,not clustering of Pr magnetic ions.Thermoelectrics were evaluated by electrical conductivity(σ),thermal conductivity(k_(e)),Seebeck coefficient(S),power factor(S^(2)),and figures of merit(ZT).The room tempe rature values of S(0.169,0.183 mV/K)and ZT(0.76,0.90)increase their thermoelectric performance.Furthermore,dielectric function,refractive index,absorption coefficientα(ω),reflectivity R(ω),and other parameters are demonstrated in detail.Therefore,researchers can develop materials with the potential for spintronic and energy harvesting.
基金supported by the National Natural Science Foundation of China(Nos.52273017 and 52273016)Strategic Priority Program of the Chinese Academy of Sciences(No.ZDRW-CN-2023-1)Natural Science Foundation of Jilin Province(No.SKL202302033).
文摘Cyclic olefin copolymers(COCs)are highly valuable optical resins,but their productions on industry are fully limited by the monomer norbornene.Although ethylene/dicyclopentadiene(E/DCPD)copolymers provide a cost-effective alternative to commercially available COCs because of using low-cost DCPD as cyclic olefin monomer,these inherent unsaturated double bonds on E/DCPD copolymers cause low heat resistance,oxidation,and crosslinking during processing and storage.And E/DCPD copolymers usually showed lower glass-transition temperature(T_(g))compared with commercially available COCs.In this study,we studied the E-DCPD copolymerization catalyzed by a scandium complex and the sequential hydrogenation catalyzed by a nickel compound to prepare saturated copolymers H-(E/DCPD).The polymerization activities are high up to 5.86×10^(6)g/(molSc·h),and the resultant H-(E/DCPD)copolymers showed narrow polymer dispersity index(PDI=1.5–2.0).By changing the polymerization conditions,a series of H-(E/DCPD)copolymers with tunable DCPD incorporation(28.4 mol%–44.9 mol%)and a wide range of T_(g)(123–171°C)were obtained.H-(E/DCPD)copolymers exhibited excellent optical properties(transparency>90%,refractive index of 1.543),similar to those of commercial COCs,making them an alternative for high-performance optical applications.This method solves the problems of traditional E/DCPD copolymers and provides a practical way to produce stable and low-cost COCs,and is comparable with commercially available COC resins.
基金supported by the National Natural Science Foundation of China (No.21801111)the Training Plan for Young Core Teachers in Higher Education of Henan Province (No.2021GGJS131)+1 种基金Natural Science Foundation of Henan Province (No.232300421232)the Heluo Young Talent Lifting Project (No.2023HLTJ02)。
文摘Ln@MOFs by anchoring rare metal ions(Ln) into metal-organic frameworks(MOFs) are proved to have great potential in the field of luminescent molecular thermometer.Nevertheless,the current research indicated that the poor structural stability and low sensitivity hindered their application scope.In this work,a new MOF Zn-450 luminescent thermometer with multiple emission fluorescence characteristics was synthesized by the combination of 3,3,5,5-biphenyl tetracarboxylic acid(H_(4)L) and Zn^(2+) ion under solvothermal conditions.Interestingly,a high relative sensitivity of 1.43 % K^(-1) was found within 80-300 K based on Zn-450.Subsequently,two high-sensitivity luminescent Ln@MOFs(Ln = Eu and Tb) were further fabricated by doping rare earth ions into Zn-450 based on the post-synthesis strategy.Among them,the Eu@Zn-450 demonstrates various luminous behaviors while achieving an increased relative sensitivity of 1.63 % K^(-1).In addition,the continuously visible red,pink,and purple luminescent emissions at the same temperature range were observed,suggesting that the Eu@Zn-450 could be utilized as a luminescent colorimetric molecular thermometer.Importantly,this work can present new possibilities for the development of rare earth-doped luminescence and its temperature sensing properties.
基金Project supported by the National Natural Science Foundation of China(52074031,51574213,51904027)the Fundamental Research Funds for the Central Universities of China(06500104)。
文摘Understanding the underlying mechanism that enhances the separation of specific target ions from complex background aqueous solutions is crucial for achieving controllable chemical reactions and industrial purification processes in modern industries.This study investigated the enhanced kinetic separatio n of target metal ions from complex aqueous solutio ns at a liquid-liquid interface,focusing on the presence of coexisting salt cations.Employing a typical thin-layer organic oil film(TOOF)extraction as a model system,the research examines how background Al^(3+)ions influence the mass transfer and separation of ions.Notably,the co ncentration of Al^(3+)ions affects both the distribution of Er^(3+)ions at the oil-water interface and the arrangement and orientation of P507 extractant molecules through the formation of unique hydrogen-bonding interactions.These interactions influence the selectivity of mass transfer,facilitating the separation of Er^(3+)from Al^(3+)ions.Specifically,the hydration shell of Er^(3+)ions is disrupted due to the strong hydration capability of coexisting Al^(3+)ions,leading to a higher interfacial concentration of Er^(3+)ions and a more ordered interfacial orientation of P507 molecules.At lower concentrations of Al^(3+)ions,the diffusion rate of Er^(3+)ions near the interface is high,enhancing the sepa ration perfo rmance of these ions.In contrast,at higher concentrations of Al^(3+)ions,the competitive hydration by Al^(3+)ions increases,and the interfacial concentration of Er^(3+)ions decreases due to enhanced diffusion resistance,resulting in poorer separation performance.Furthermore,a thinner membrane is more effective than a thicker one in enriching target Er^(3+)ions at the interface and achieving an ordered interfacial orientation of P507 molecules,thereby enhancing the separation coefficient(β_(Er/Al)).This work provides novel insights into the behaviors of ions and extractants at oil-wate r interface and the kinetic separation selectivity under varying concentrations of coexisting salt cations.
基金Project supported by the National Key R&D Program of China(2022YFC2905800)the National Natural Science Foundation of China(52174242)the National Youth Talent Support Program(QNBJ-2023-03)。
文摘Bayan Obo rare earth mine is the largest light rare earth resource worldwide,primarily extracts rare earth elements(REEs)from mixed RE concentrates with bastnaesite and monazite.Nevertheless,the adoption of the concentrated sulfuric acid roasting metallurgical process has resulted in damage to the environment.Therefore,this paper adopted the method of selective mineral phase transformation(MPT)followed by enhanced micro-flotation.By determining the optimal MPT co nditions,the flotation recovery of bastnaesite-roasted products by the collector(phthalic acid,PA)is improved,and the enhanced separation of bastnaesite with monazite is realized.The results show that with the increase of roasting temperature and time,the bastnaesite decomposition product is CeOF and monazite does not change significantly.Subsequent micro-flotation exhibits a gradual decline in the PA consumption of bastnaesiteroasted products,while the flotation recovery of monazite-roasted products remains poor.The artificial mixed ore experiments result in a CeOF foam product with a content of 94.14%and a recovery of 85.80%,and a monazite tank product with a content of 73.53%and a recovery of 87.87%.Compared with the preroasting ore,the surface and interior of bastnaesite-roasted products develop numerous cracks and porosities,and no obvious structural damage is observed in monazite-roasted particles.As the roasting temperature increases,the mineral particles undergo recrystallization or closure,reducing the specific surface area of bastnaesite-roasted products and enhancing hydrophobicity,leading to diminished PA consumption.Fourier transform infrared and other flotation-relation tests show that PA is chemisorbed on the surface of CeOF.The MPT conditions are optimized in this study,which provides a reference for further advancing the efficient separation of bastnaesite and monazite.
基金Project supported by the National Key Research and Development Program of China(2022YFC2905800)National Natural Science Foundation of China(52374276,52274269)+2 种基金Yunnan Fundamental Re search Projects(202401AS070051)the Natural Science Foundation of Hubei Province of China(2024AFD123)Young Elite Scientists Sponsorship Program by CAST(YESS20200276)。
文摘The efficient flotation separation of rare earth elements(REEs)from gangue minerals is crucial in mineral processing.This study synthesized a quaternary ammonium salt ionic liquid collector,tetrabutylammonium salicylhydroxamate(T-S),and investigated its performance in separating bastnaesite and fluorite.T-S was synthesized from salicylhydroxamic acid(SHA)and tetrabutylammonium chloride(TBAC),and its molecular structure was characterized using Fourier transform infrared(FTIR)spectroscopy.Microflotation tests indicate that T-S outperforms SHA and TBAC in both collecting ability and selectivity for bastnaesite.Adsorption,zeta potential,and infrared spectroscopy measurements reveal that T-S exhibits stronger adsorption on bastnaesite compared to SHA and TBAC.X-ray photoelectron spectroscopy(XPS)and molecular dynamics simulations(MDS)results confirm that chemical adsorption occurs between Ce on the bastnaesite surface and the-C(=O)NHOH groups of T-S.Moreover,the interaction between T-S and the bastnaesite surface is stronger than that with the fluorite surface.This work provides valuable insights for designing ionic liquid collectors for the flotation separation of bastnaesite and fluorite.
基金supported by the National Natural Science Foundation of China(81760037)Yunling Scholar Project of Yunnan Province(YNWR-YLXZ-2019-0005)+1 种基金Hunan Provincial Innovation Platform and Talent Program(2018SK4004)Hunan Provincial Natural Science Foundation(2019JJ80048).
文摘The occurrence of severe thalassemia,an inherited blood disorder that is either blood-transfusiondependent or fatal,can be mitigated through carrier screening.Here,we aim to evaluate the effectiveness and outcomes of pre-conceptional and early pregnancy screening initiatives for severe thalassemia prevention in a diverse population of 28,043 women.Using next-generation sequencing(NGS),we identify 4,226(15.07%)thalassemia carriers across 29 ethnic groups and categorize them into high-(0.75%),low-(25.86%),and unknown-risk(69.19%)groups based on their spouses'screening results.Post-screening follow-up reveals 59 fetuses with severe thalassemia exclusively in high-risk couples,underscoring the efficacy of risk classification.Among 25,053 live births over 6 months of age,two severe thalassemia infants were born to unknown-risk couples,which was attributed to incomplete screening and late NGS-based testing for a rare variant.Notably,64 rare variants are identified in 287 individuals,highlighting the genetic heterogeneity of thalassemia.We also observe that migrant flow significantly impacts carrier rates,with 93.90%of migrants to Chenzhou originating from high-prevalence regions in southern China.Our study demonstrates that NGS-based screening during pre-conception and early pregnancy is effective for severe thalassemia prevention,emphasizing the need for continuous screening efforts in areas with high and underestimated prevalence.
基金Project supported by the National Key Research and Development Program of China(2022YFB3503302)the Major Projects in Inner Mongolia Autonomous Region(20212D0035)the High-quality Development Special Funds Program Ministry of Industry Technology(TC220H06G)。
文摘The optimization of microstructure represents a significant methodology for enhancing coercivity(Hcj).This paper concentrates on optimizing the microstructure of magnets through the manipulation of the composition of low-melting-point and high-melting-point elements,thereby achieving the objective of augmenting the comprehensive magnetic properties of magnets.The present study is concerned with the microstructure of magnets comprising three distinct Ga and B contents,and the associated changes in their magnetic properties.The findings indicate that when the Ga content is 0.5 wt%and the B content is 0.88 wt%,the coercivity of the magnets is markedly enhanced.This is evidenced by an increase in coercivity from 8.51 to 14.83 kOe,representing a 74.26%rise.Concurrently,the residual magnetization strength of the magnet remains unaltered.This finding provides a crucial foundation for optimizing the overall magnetic properties of the magnets.The microstructural analysis indicates that a reduction in B content coupled with an increase in Ga content leads to the melting of sharp angles on the surface of the main-phase grains,facilitated by low-melting-point rare-earth-rich phases.This process results in the migration of Fe from the grain boundaries(GBs)to the triple junction phases(TJPs),while Nd migrates from the TJPs to the GBs.This migration results in a reduction in the agglomeration of rare-earth-rich elements within the TJPs,thereby increasing the Nd content in the GBs.This increase enhances the wettability of the GBs,while the reduction of Fe content in this phase mitigates the exchange-coupling effect between the main-phase GBs.Consequently,the GBs become more smooth,more homogeneous and more continuous,which ultimately results in an enhancement of the coercivity of the magnets.
