The rapid advancement of modern science and technology,coupled with the recent surge in new-energy electric vehicles,has significantly boosted the demand for lithium.This has promoted the development and efficient uti...The rapid advancement of modern science and technology,coupled with the recent surge in new-energy electric vehicles,has significantly boosted the demand for lithium.This has promoted the development and efficient utilization of lepidolite as a lithium source.Therefore,the processes for the flotation of lepidolite have been studied in depth,particularly the development and use of lepidolite flotation collectors and the action mechanism of the collectors on the lepidolite surface.Based on the crystal-structure characteristics of lepidolite minerals,this review focuses on the application of anionic collectors,amine cationic collectors(primary amines,quaternary ammonium salts,ether amines,and Gemini amines),and combined collectors to the flotation behavior of lepidolite as well as the adsorption mechanisms.New directions and technologies for the controllable flotation of lepidolite are proposed,including process improvement,reagent synthesis,and mechanistic research.This analysis demonstrates the need for the further study of the complex environment inside lepidolite and pulp.By using modern analytical detection methods and quantum chemical calculations,research on reagents for the flotation of lepidolite has expanded,providing new concepts and references for the efficient flotation recovery and utilization of lepidolite.展开更多
As a primary type of clean energy,methane is also the second most important greenhouse gas after CO_(2)due to the high global warming potential.Large quantities of lean methane(0.1–1.0 vol%)are emitted into the atmos...As a primary type of clean energy,methane is also the second most important greenhouse gas after CO_(2)due to the high global warming potential.Large quantities of lean methane(0.1–1.0 vol%)are emitted into the atmosphere without any treatment during coal mine,oil,and natural gas production,thus leading to energy loss and greenhouse effect.In general,it is challenging to utilize lean methane due to its low concentration and flow instability,while catalytic combustion is a vital pathway to realize an efficient utilization of lean methane owing to the reduced emissions of polluting gases(e.g.,NOxand CO)during the reaction.In particular,to efficiently convert lean methane,it necessitates both the designs of highly active and stable heterogeneous catalysts that accelerate lean methane combustion at low temperatures and smart reactors that enable autothermal operation by optimizing heat management.In this review,we discuss the in-depth development,challenges,and prospects of catalytic lean methane combustion technology in various configurations,with particular emphasis on heat management from the point of view of material design combined with reactor configuration.The target is to describe a framework that can correlate the guiding principles among catalyst design,device innovation and system optimization,inspiring the development of groundbreaking combustion technology for the efficient utilization of lean methane.展开更多
BACKGROUND:Shared decision-making(SDM)has broad application in emergencies.Most published studies have focused on SDM for a certain disease or expert opinions on future research gaps without revealing the full picture...BACKGROUND:Shared decision-making(SDM)has broad application in emergencies.Most published studies have focused on SDM for a certain disease or expert opinions on future research gaps without revealing the full picture or detailed guidance for clinical practice.This study is to investigate the optimal application of SDM to guide life-sustaining treatment(LST)in emergencies.METHODS:This study was a prospective two-round Delphi consensus-seeking survey among multiple stakeholders at the China Consortium of Elite Teaching Hospitals for Residency Education.Participants were identified based on their expertise in medicine,law,administration,medical education,or patient advocacy.All individual items and questions in the questionnaire were scored using a 5-point Likert scale,with responses ranging from"very unimportant"(a score of 1)to"extremely important"(a score of 5).The percentages of the responses that had scores of 4-5on the 5-point Likert scale were calculated.A Kendall’s W coefficient was calculated to evaluate the consensus of experts.RESULTS:A two-level framework consisting of 4 domains and 22 items as well as a ready-touse checklist for the informed consent process for LST was established.An acceptable Kendall’s W coefficient was achieved.CONCLUSION:A consensus-based framework supporting SDM during LST in an emergency department can inform the implementation of guidelines for clinical interventions,research studies,medical education,and policy initiatives.展开更多
The flotation of complex solid–liquid multiphase systems involve interactions among multiple components,the core problem facing flotation theory.Meanwhile,the combined use of multicomponent flotation reagents to impr...The flotation of complex solid–liquid multiphase systems involve interactions among multiple components,the core problem facing flotation theory.Meanwhile,the combined use of multicomponent flotation reagents to improve mineral flotation has become an important issue in studies on the efficient use of refractory mineral resources.However,studying the flotation of complex solid–liquid systems is extremely difficult,and no systematic theory has been developed to date.In addition,the physical mechanism associated with combining reagents to improve the flotation effect has not been unified,which limits the development of flotation theory and the progress of flotation technology.In this study,we applied theoretical thermodynamics to a solid–liquid flotation system and used changes in the entropy and Gibbs free energy of the reagents adsorbed on the mineral surface to establish thermodynamic equilibrium equations that de-scribe interactions among various material components while also introducing adsorption equilibrium constants for the flotation reagents adsorbed on the mineral surface.The homogenization effect on the mineral surface in pulp solution was determined using the chemical potentials of the material components of the various mineral surfaces required to maintain balance.The flotation effect can be improved through synergy among multicomponent flotation reagents;its physical essence is the thermodynamic law that as the number of compon-ents of flotation reagents on the mineral surface increases,the surface adsorption entropy change increases,and the Gibbs free energy change of adsorption decreases.According to the results obtained using flotation thermodynamics theory,we established high-entropy flotation theory and a technical method in which increasing the types of flotation reagents adsorbed on the mineral surface,increasing the adsorption entropy change of the flotation reagents,decreasing the Gibbs free energy change,and improving the adsorption efficiency and stability of the flotation reagents improves refractory mineral flotation.展开更多
Mineral fulvic acid(MFA)was used as an eco-friendly pyrite depressant to recover chalcopyrite by flotation with the use of the butyl xanthate as a collector.Flotation experiments showed that MFA produced a stronger in...Mineral fulvic acid(MFA)was used as an eco-friendly pyrite depressant to recover chalcopyrite by flotation with the use of the butyl xanthate as a collector.Flotation experiments showed that MFA produced a stronger inhibition effect on pyrite than on chalcopyrite.The separation of chalcopyrite from pyrite was realized by introducing 150 mg/L MFA at a pulp pH of approximately 8.0.The copper grade,copper recovery,and separation efficiency were 28.03%,84.79%,and 71.66%,respectively.Surface adsorption tests,zeta potential determinations,and localized electrochemical impedance spectroscopy tests showed that more MFA adsorbed on pyrite than on chalcopyrite,which weakened the subsequent interactions between pyrite and the collector.Atomic force microscope imaging further confirmed the adsorption of MFA on pyrite,and X-ray photoelectron spectroscopy results indicated that hydrophilic Fe-based species on the pyrite surfaces increased after exposure of pyrite to MFA,thereby decreasing the floatability of pyrite.展开更多
Tin is a critical metal for various industries,making its recovery from low-grade cassiterite ores crucial.This study aimed to optimize the flotation recovery of cassiterite using multi-component collector systems.Sev...Tin is a critical metal for various industries,making its recovery from low-grade cassiterite ores crucial.This study aimed to optimize the flotation recovery of cassiterite using multi-component collector systems.Several collectors were initially selected through micro-flotation tests,leading to the identification of optimal proportions for a four-component collector system(SHA-OHA-SPA-DBIA in a 4:3:2:1 ratio).Molecular dynamics simulations and surface tension tests were used to investigate the micellar behavior of these collectors in aqueous solution.The adsorption characteristics were quantified using microcalorimetry,enabling the determination of collection entropy and changes in Gibbs free energy.The four-component collector system showed the highest entropy change and the most favorable Gibbs free energy,leading to a cassiterite recovery of above 90%at a concentration of 8.0×10^(5)mol/L.Various analytical techniques were employed to systematically characterize the adsorption mechanism.The findings revealed a positive correlation between the adsorption products formed by the multicomponent collectors on the cassiterite surface and the entropy changes.Industrial-scale testing of the high-entropy collector system produced a tin concentrate with an Sn grade of 6.17%and an Sn recovery of 82.43%,demonstrating its substantial potential for practical applications in cassiterite flotation.展开更多
The surface states of pyrite(Fe S2) were theoretically investigated using first principle calculation based on the density functional theory(DFT). The results indicate that both the(200) and(311) surfaces of pyrite un...The surface states of pyrite(Fe S2) were theoretically investigated using first principle calculation based on the density functional theory(DFT). The results indicate that both the(200) and(311) surfaces of pyrite undergo significant surface atom relaxation after geometry optimization, which results in a considerable distortion of the surface region. In the normal direction, i.e., perpendicular to the surface, S atoms in the first surface layer move outward from the bulk, while Fe atoms move toward the bulk, forming an S-rich surface. The surface relaxation processes are driven by electrostatic interaction, which is evidenced by a relative decrease in the surface energy after surface relaxation. Such a relaxation process is visually interpreted through the qualitative analysis of molecular mechanics. Atomic force microscopy(AFM) analysis reveals that only sulfur atom is visible on the pyrite surface. This result is consistent with the DFT data. Such S-rich surface has important influence on the flotation properties of pyrite.展开更多
This study investigated the effect of konjac glucomannan(KGM)on the flotation separation of calcite and scheelite.Micro-flotation tests showed that under the action of 50 mg/L KGM,the floatability of calcite notably d...This study investigated the effect of konjac glucomannan(KGM)on the flotation separation of calcite and scheelite.Micro-flotation tests showed that under the action of 50 mg/L KGM,the floatability of calcite notably decreased,while the impact on scheelite was negligible,resulting in a recovery difference of 82.53%.Fourier transform infrared(FTIR)spectroscopy and atomic force micro-scopy(AFM)analyses indicated the selective adsorption of KGM on the calcite surface.Test results of the zeta potential and UV-visible absorption spectroscopy revealed that KGM prevented the adsorption of sodium oleate on the calcite surface.X-ray photoelectron spec-troscopy(XPS)analysis further confirmed the chemical adsorption of KGM on the calcite surface and the formation of Ca(OH)_(2).The density functional theory(DFT)simulation results were consistent with the flotation tests,demonstrating the strong adsorption perform-ance of KGM on the calcite surface.This study offers a pathway for highly sustainable and cost-effective mineral processing by utilizing the unique properties of biopolymers such as KGM to separate valuable minerals from gangue minerals.展开更多
Molten salt gasification is a promising technology for biomass conversion due to its advantages of superior heat transfer and the ability of utilizing solar energy to reduce carbon emission.In this study,the character...Molten salt gasification is a promising technology for biomass conversion due to its advantages of superior heat transfer and the ability of utilizing solar energy to reduce carbon emission.In this study,the characteristics of corncob CO_(2)-gasification in molten salt environments is thoroughly investigated,and the approach of introducing Fe_(2)O_(3) as catalyst to enhance the syngas yield is proposed.The results showed that the molten salts significantly promoted the conversion of corncob into gaseous products with very low tar and char yield.Compared to O_(2) and H_(2)O atmospheres,utilizing CO_(2) as gasifying agent enhanced the yield of gaseous products during the corncob gasification,especially the yields of CO and H_(2).The introduction of Fe_(2)O_(3) as a catalyst could further increase the yield of gaseous products and the cold gas efficiency(CGE),and the yield of syngas was increased into 2258.3 ml·g^(−1) with a high CGE of 105.8%in 900℃.The findings evidenced that CO_(2) gasification in the molten salt environment with Fe_(2)O_(3) addition can promote the cracking of tar,increasing the syngas yield significantly.Moreover,the energy required to drive the gasification process was calculated,and the total energy consumption was calculated as 16.83 GJ·t^(−1).The study opened up a new solution for the biomass gasification,exhibiting a great potential in distributed energy or chemical systems.展开更多
Magnesium(Mg),as one of the most abundant elements in earth's crust,is the lightest structural metal with extensive applications across various industries.However,the performance of Mg-based products is highly dep...Magnesium(Mg),as one of the most abundant elements in earth's crust,is the lightest structural metal with extensive applications across various industries.However,the performance of Mg-based products is highly dependent on their impurity levels,and the lack of high-purity Mg,along with efficient purification method,has posed significant challenge to its widespread industrial adoption.This study investigates the impurity behavior in Mg ingots during the vacuum gasification purification process.Through the analysis of binary phase diagrams,iron(Fe)-based foam material was selected for the filtration and purification of Mg vapor in a vacuum tube furnace.A novel approach combining vacuum gasification,vapor purification,and directional condensation is proposed.The effect of filter pore sizes and filtration temperatures on the efficacy of impurity removal was evaluated.Experimental results demonstrate that Fe-based foam with a pore size of 60 ppi,at a filtration temperature of 773 K,effectively removes impurities such as calcium(Ca),potassium(K),sodium(Na),manganese(Mn),silicon(Si),aluminum(Al),and various oxides,sulfides,and chlorides from the vapor phase.Consequently,high-purity Mg with a purity level exceeding 5N3 was obtained in the condensation zone.展开更多
Magnesium(Mg)alloys are widely used lightweight structural materials for automobiles and help reduce carbon emissions.However,their use increases the production of Mg alloy scrap,which is recycled at a much lower rate...Magnesium(Mg)alloys are widely used lightweight structural materials for automobiles and help reduce carbon emissions.However,their use increases the production of Mg alloy scrap,which is recycled at a much lower rate than aluminum,and its greater complexity poses challenges to existing recycling processes.Although vacuum distillation can be used to recycle Mg alloy scrap,this requires optimizing and maximizing metal recirculation,but there has been no thermodynamic analysis of this process.In this study,the feasibility and controllability of separating inclusions and 23 metal impurities were evaluated,and their distribution and removal limits were quantified.Thermodynamic analyses and experimental results showed that inclusions and impurity metals of separation coefficient lgβ_(i)≤-5,including Cu,Fe,Co,and Ni below 0.001 ppm,could be removed from the matrix.All Zn entered the recycled Mg,while impurities with-1<lgβ_(i)<-5 such as Li,Ca,and Mn severely affected the purity of the recycled Mg during the later stage of distillation.Therefore,an optimization strategy for vacuum distillation recycling:lower temperatures and higher system pressures for Zn separation in the early stage,and the early termination of the recovery process in the later stage or a continuous supply of raw melt can also prevent contamination during recycling.The alloying elements Al and Zn in Mg alloy scrap can be further recovered and purified by vacuum distillation when economically feasible,to maximize the recycling of metal resources.展开更多
Immune checkpoint inhibitors have markedly improved outcomes in patients with multiple advanced malignancies.However,their widespread use has markedly increased the incidence of immune-related adverse events(irAEs).ir...Immune checkpoint inhibitors have markedly improved outcomes in patients with multiple advanced malignancies.However,their widespread use has markedly increased the incidence of immune-related adverse events(irAEs).irAEs can affect a wide range of organ systems and are characterized by heterogeneous onset,broad toxicity spectra,and complex management requirements,thus ultimately impairing treatment continuation and patient quality of life.This review systematically summarizes the epidemiological features,clinical progression,and current management of irAEs.Existing guidelines largely focus on acute toxicities but have not provided structured strategies for chronic,delayed-onset,or multisystem irAEs.Moreover,clinical practice is hampered by incomplete multidisciplinary collaboration,insufficient training of oncologists,and fragmented treatment pathways,all of which limit the efficacy of irAE management.We propose incorporating irAE management into core oncology training and call for the establishment of comprehensive interdisciplinary frameworks to ensure the standardized long-term use of immunotherapy.展开更多
Background:Hypereosinophilia(HE)is a rare disease characterized by an increase in eosinophils.Suplatast tosilate is a selective Th2 cytokine inhibitor.This case report presents the course and prognosis of a patient wi...Background:Hypereosinophilia(HE)is a rare disease characterized by an increase in eosinophils.Suplatast tosilate is a selective Th2 cytokine inhibitor.This case report presents the course and prognosis of a patient with hypereosinophilia treated with suplatast tosilate monotherapy.Case presentation:A 41-year-old female patient who complained of“Elevated blood eosinophils were found during physical examination for more than 2 months”visited the Allergy Department.The systematic screening results of parasites,autoantibodies spectrum,tumor markers,peripheral blood morphology analysis,and leukemia fusion gene(FIP1L1-PDGFRα)were all negative.Gastrointestinal endoscopy only indicated mild gastritis.The dust mites and multiple fungal mixtures were weakly positive in intradermal tests.Finally diagnosed HE.After treatment with suplatast tosilate 2 months of 100mg three times daily,the blood eosinophils decreased to normal.Then,maintenance treatment with 50mg three times a day for 3 months.And without recurrence during nearly five years of follow-up.Conclusion:The report indicates that suplatast tosilate can reduce peripheral blood eosinophils levels in patients with HE,and may be a reliable option for individualized treatment of HE.However,there is still no consensus on whether suplatast tosilate can be used as a first-line treatment or as an adjuvant therapy to reduce the corticosteroids dosage for patients with eosinophilia,and further research is needed.展开更多
Varicocele(VC)is a common cause of male infertility,yet there is a lack of molecular information for VC-associated male infertility.This study investigated alterations in the seminal plasma metabolomic and lipidomic p...Varicocele(VC)is a common cause of male infertility,yet there is a lack of molecular information for VC-associated male infertility.This study investigated alterations in the seminal plasma metabolomic and lipidomic profiles of infertile male VC patients.Twenty infertile males with VC and twenty-three age-matched healthy controls(HCs)were recruited from Peking Union Medical College Hospital(Beijing,China)between October 2019 and April 2021.Untargeted metabolite and lipid profiles from seminal plasma were analyzed using mass spectrometry.Four hundred and seventy-six metabolites and seventeen lipids were significantly different in infertile male VC patients compared to HCs.The top enriched pathways among these significantly different metabolites are protein digestion and absorption,aminoacyl-transfer RNA(tRNA)biosynthesis,and biosynthesis of amino acids.Different key lipid species,including triglyceride(TG),diacylglycerol(DG),ceramides(Cer),and phosphatidylserine(PS),varied betweenVC and HC groups.The distinct metabolites and lipids were moderately correlated.DL-3-phenyllactic acid is a potential diagnostic biomarker for VC-related male infertility(area under the curve[AUC]=0.893),positively correlating with sperm count,concentration,and motility.Furthermore,DL-3-phenyllactic acid is the only metabolite shared by all four comparisons(VC vs HC,VC-induced oligoasthenospermia[OAS]vs VC-induced asthenospermia[AS],OAS vs HC,and AS vs HC).DL-3-phenyllactic acid significantly decreased in OAS than AS.Metabolite-targeting gene analysis revealed carbonic anhydrase 9(CA9)might be the strongest candidate associated with the onset and severity of VC.The seminal plasma metabolite and lipid profiles of infertile males with VC differ significantly from those of HCs.DL-3-phenyllactic acid could be a promising biomarker.展开更多
Atopic dermatitis(AD)is one of the most common chronic inflammatory skin diseases.It usually develops in childhood and may persist into adulthood.Dupilumab is a fully human monoclonal antibody directed against interle...Atopic dermatitis(AD)is one of the most common chronic inflammatory skin diseases.It usually develops in childhood and may persist into adulthood.Dupilumab is a fully human monoclonal antibody directed against interleukin-4R-alpha,the common chain of interleukin-4 and interleukin-13 receptors.Dupilumab showed clinical improvements in patients with atopic dermatitis,asthma,and chronic rhinosinusitis and is currently under development for other indications.However,there are many adverse effects reported after dupilumab therapy including local injection site reactions,conjunctivitis,headache,and nasopharyngitis.We report a new case of a 4-year-old child who experienced anaphylaxis after dupilumab injection.In addition to,we summary and disscuss the rare adverse reactions caused by dupilumab injection by searching the literature in pubmed.展开更多
Background:Developmental dysplasia of the hip(DDH)is a prevalent pediatric condition with a multifactorial etiology.Its incidence varies geographically,with notably higher rates observed on the Xizang plateau.This stu...Background:Developmental dysplasia of the hip(DDH)is a prevalent pediatric condition with a multifactorial etiology.Its incidence varies geographically,with notably higher rates observed on the Xizang plateau.This study was performed to evaluate the lipidomics signatures associated with DDH by analyzing plasma samples.Methods:Fifty infants were recruited,including 25 diagnosed with DDH and 25 age-matched healthy controls.In addition to plasma samples,comprehensive laboratory test results and medical records were collected for each participant.An untargeted lipidomics profiling approach was employed to identify distinguishing metabolic signatures.Results:Lipidomics profiles differed significantly between patients with DDH and healthy controls.Several differential metabolites were identified,including triacylglycerol(TAG)(17:0/18:1/20:1),TAG(17:0/17:0/17:0),phosphatidylethanolamine(PE)(10:0/26:4),TAG(17:0/18:0/18:0),TAG(16:0/17:0/22:1),TAG(16:0/18:0/22:0),TAG(17:0/19:0/19:0),TAG(13:0/20:0/20:0),TAG(18:0/18:0/22:0),and TAG(16:0/20:0/20:0).The primary lipid species showing differences were TAGs and PE.Conclusions:Distinct shifts in lipidomics profiles were observed in infants with DDH.To the best of our knowledge,this study is the first to explore lipidomics signatures in patients with DDH.The combined assessment of TAG(17:0/18:1/20:1)and TAG(17:0/17:0/17:0)may serve as a potential diagnostic tool for DDH.展开更多
Electroreduction of CO_(2) into beneficial products is integral to attaining carbon neutrality.Herein,we detail a series of anti-perovskite nitrides InNNi_(3−x)V_(x)(x=0,0.2,0.4,0.6,0.8)to be highly effective CO_(2)RR...Electroreduction of CO_(2) into beneficial products is integral to attaining carbon neutrality.Herein,we detail a series of anti-perovskite nitrides InNNi_(3−x)V_(x)(x=0,0.2,0.4,0.6,0.8)to be highly effective CO_(2)RR.The InNNi_(2.4)V_(0.6) demonstrated exceptional conversion of CO_(2) to formate,achieving an optimal Faraday efficiency(FE)of 93.6%at−0.754 V versus RHE.It also exhibited a partial current density of 200 mA cm^(−2) at−1.1 V versus RHE,along with remarkable stability in an H-type cell.Electrochemical tests,X-ray absorption fine structure,and theoretical calculations demonstrated that in addition to altering InNNi_(3) electronic structure,V doping results in lattice distortion in NiN_(3) octahedron,increasing the lattice spacing of InNNi_(2.4)V_(0.6)(111)surface,exposing more active sites.This enhances its ability to adsorb the reaction intermediate ^(*)OCHO,thereby facilitating the conversion of CO_(2) into formate.This research offers a viable approach for optimizing an electrocatalyst to convert CO_(2) to valuable products.展开更多
Energy shortages and global warming are driving the focus on the greenhouse gases CH_(4)and CO_(2).The main reason why dry reforming of methane(DRM)has yet to be industrialized is its catalytic tendency to deactivate ...Energy shortages and global warming are driving the focus on the greenhouse gases CH_(4)and CO_(2).The main reason why dry reforming of methane(DRM)has yet to be industrialized is its catalytic tendency to deactivate due to carbon deposition or sintering.Single-atom Ni/CeO_(2)catalysts with suitable metalsupport interactions may provide a new strategy for developing highly active and coking-resistant nickel-based catalysts.In this work,we investigated the properties of the catalytic models of singleatom Ni loaded on CeO_(2)(111),CeO_(2)(110)and CeO_(2)(100),as well as their catalytic DRM performance with the density functional theory method(DFT).The interaction of CeO_(2)with different low-index crystal planes and single-atom Ni can be explained by the anchoring effect of surface O ions on Ni.Adsorption energies,growth patterns of Ni clusters,and migration studies of Ni atoms all indicate that the CeO_(2)(100)surface has the strongest anchoring effect on isolated Ni atoms,followed by the CeO_(2)(110)surface,with the CeO_(2)(111)surface being the weakest,Methane activation studies have shown that the activation ability of Ni_(1)/CeO_(2)(110)for methane strongly depends on the coordination environment of Ni,By contrast,methane activation by Ni on Ni_(1)/CeO_(2)(111)exhibits better activity and stability.Moreover,the Ni—CeO_(2)interaction correlates well with the DRM reaction performance.Interactions that are too strong anchor Ni atoms well but are not optimal for DRM activity.Ni_(1)/CeO_(2)(110)has relatively moderate interactions,promotes the^(*)CH_(4)→^(*)CH process,and has good resistance to carbon deposition.The metalsupport interaction-DRM reactivity(or stability)relationship is vital for the design of"super"highactivity and high-stability DRM catalysts.展开更多
The superconducting high gradient magnetic separation(S-HGMS)technology can be used to effectively extract silica from iron ore tailings(IOTs).However,particle agglomeration in strong magnetic fields poses a challenge...The superconducting high gradient magnetic separation(S-HGMS)technology can be used to effectively extract silica from iron ore tailings(IOTs).However,particle agglomeration in strong magnetic fields poses a challenge in achieving optimal performance.In this study,we investigated the agglomeration of IOT particles and the mechanisms for its inhibition through surface analysis,density functional theory(DFT),and extended Derjaguin-Landau-Verwey-Overbeek(EDLVO)theory.Hematite was found to exhibit the highest magnetic moment among the minerals present in IOTs,making it particularly prone to magnetic agglomeration.The addition of the dispersant SDSH into the slurry was essential in promoting the dispersion of IOT particles during the S-HGMS process.This dispersant hydrolyzed to form HPO_(4)^(2-)and RSO_(3)^(-)groups in the solution,which then chemically adsorbed onto the metal ions exposed on the surfaces of non-quartz particles,increasing interparticle electrostatic repulsion.Furthermore,the RSO_(3)^(-)groups physically adsorbed onto the surface of quartz particles,resulting in strong steric repulsion and enhancing the hydrophilicity of the particle surfaces,thereby inhibiting magnetic agglomeration between the particles.Under optimal conditions,the SiO_(2)grade of the obtained high-grade silica powder increased from an initial value of 76.32%in IOTs to 97.42%,achieving a SiO_(2)recovery rate of 54.81%,which meets the requirements for quartz sand used in glass preparation.This study provides valuable insights into the magnetic agglomeration of IOT particles and its inhibition while providing a foundation for regulating S-HGMS processes.展开更多
Smelting with oxygen bottom blowing is one of the main methods used in the frame of copper pyrometallurgy.With this approach,feed materials and oxygen-enriched air are introduced in reversed order to enhance multiphas...Smelting with oxygen bottom blowing is one of the main methods used in the frame of copper pyrometallurgy.With this approach,feed materials and oxygen-enriched air are introduced in reversed order to enhance multiphaseflow within the furnace.Understanding the flow structure and temperature distribution in this setup is crucial foroptimizing production.In this study,gas-liquid interactions,and temperature profiles under varying air-injectionconditions are examined by means of numerical simulation for a 3.2 m×20 m furnace.The results indicate that thehigh-velocity regions are essentially distributed near the lance within the reaction region and the flue gas outlet,while low-velocity regions are located close to the furnace walls on both side of the reaction region.Dead regionsappear in the sedimentation region,with gas velocities surpassing those of the molten phase.As the injection rateincreases from 0.50 to 0.80 Nm3/s,the stabilization time of the average liquid surface velocity decreases from 2.6 sto 1.9 s,exhibiting a similar trend to the gas holdup.During stabilization,the average liquid surface velocity risesfrom 0.505 to 0.702 m/s.The average turbulent kinetic energy(TKE)of the fluid in the molten bath increases from0.095 to 0.162 m^(2)/s^(2).The proportion of the area distribution with TKE greater than 0.10 m^(2)/s^(2) and the gas holdupat steady state both rise with an increase in the injection quantity.The maximum splashing height of the melt growsfrom approximately 0.756 to 1.154 m,with the affected area expanding from 14.239 to 20.498 m^(2).Under differentworking conditions with varying injection quantities,the average temperature changes in melt zone and flue gaszone of the furnace are small.The temperature in the melt and in the flue-gas zone spans the interval 1200℃–1257℃,and 1073℃–1121℃,respectively.The temperature distribution of the melt and flue gas reveals a patterncharacterized by elevated temperatures in the reaction zone,gradually transitioning to lower temperatures in thesedimentation region.展开更多
基金financially supported by the Excellent Youth Scholars Program of State Key Laboratory of Complex Nonferrous Metal Resource Clean Utilization,Kunming University of Science and Technology,China(No.YXQN-2024003)the Central Government-Guided Local Science and Technology Development Fund Project,China(No.202407AB110022)。
文摘The rapid advancement of modern science and technology,coupled with the recent surge in new-energy electric vehicles,has significantly boosted the demand for lithium.This has promoted the development and efficient utilization of lepidolite as a lithium source.Therefore,the processes for the flotation of lepidolite have been studied in depth,particularly the development and use of lepidolite flotation collectors and the action mechanism of the collectors on the lepidolite surface.Based on the crystal-structure characteristics of lepidolite minerals,this review focuses on the application of anionic collectors,amine cationic collectors(primary amines,quaternary ammonium salts,ether amines,and Gemini amines),and combined collectors to the flotation behavior of lepidolite as well as the adsorption mechanisms.New directions and technologies for the controllable flotation of lepidolite are proposed,including process improvement,reagent synthesis,and mechanistic research.This analysis demonstrates the need for the further study of the complex environment inside lepidolite and pulp.By using modern analytical detection methods and quantum chemical calculations,research on reagents for the flotation of lepidolite has expanded,providing new concepts and references for the efficient flotation recovery and utilization of lepidolite.
基金financially supported by the National Natural Science Foundation of China(21922606,21876139)the National Natural Science Foundation of Shaanxi Province(2020JQ-919)+2 种基金the Shaanxi Natural Science Fundamental Shaanxi Coal Chemical Joint Fund(2019JLM-14)the Initial Scientific Research Fund for Special Zone’s Talents(XJ18T06)K.C.Wong Education Foundation。
文摘As a primary type of clean energy,methane is also the second most important greenhouse gas after CO_(2)due to the high global warming potential.Large quantities of lean methane(0.1–1.0 vol%)are emitted into the atmosphere without any treatment during coal mine,oil,and natural gas production,thus leading to energy loss and greenhouse effect.In general,it is challenging to utilize lean methane due to its low concentration and flow instability,while catalytic combustion is a vital pathway to realize an efficient utilization of lean methane owing to the reduced emissions of polluting gases(e.g.,NOxand CO)during the reaction.In particular,to efficiently convert lean methane,it necessitates both the designs of highly active and stable heterogeneous catalysts that accelerate lean methane combustion at low temperatures and smart reactors that enable autothermal operation by optimizing heat management.In this review,we discuss the in-depth development,challenges,and prospects of catalytic lean methane combustion technology in various configurations,with particular emphasis on heat management from the point of view of material design combined with reactor configuration.The target is to describe a framework that can correlate the guiding principles among catalyst design,device innovation and system optimization,inspiring the development of groundbreaking combustion technology for the efficient utilization of lean methane.
基金supported by the China Medical BoardOpen Competition Program(20-378)Peking University Third Hospital Fund for Returned Scholars(BYSYLXHG2020004)+1 种基金JX was supported by the Peking Union Medical College Fund for Informatization of Postgraduate Courses(2021YXX001)YLZ was supported by the Sichuan University Graduate Education Reform Project(GSSCU2021046)。
文摘BACKGROUND:Shared decision-making(SDM)has broad application in emergencies.Most published studies have focused on SDM for a certain disease or expert opinions on future research gaps without revealing the full picture or detailed guidance for clinical practice.This study is to investigate the optimal application of SDM to guide life-sustaining treatment(LST)in emergencies.METHODS:This study was a prospective two-round Delphi consensus-seeking survey among multiple stakeholders at the China Consortium of Elite Teaching Hospitals for Residency Education.Participants were identified based on their expertise in medicine,law,administration,medical education,or patient advocacy.All individual items and questions in the questionnaire were scored using a 5-point Likert scale,with responses ranging from"very unimportant"(a score of 1)to"extremely important"(a score of 5).The percentages of the responses that had scores of 4-5on the 5-point Likert scale were calculated.A Kendall’s W coefficient was calculated to evaluate the consensus of experts.RESULTS:A two-level framework consisting of 4 domains and 22 items as well as a ready-touse checklist for the informed consent process for LST was established.An acceptable Kendall’s W coefficient was achieved.CONCLUSION:A consensus-based framework supporting SDM during LST in an emergency department can inform the implementation of guidelines for clinical interventions,research studies,medical education,and policy initiatives.
基金supported by the Yunnan Science and Technology Leading Talent Project(No.202305AB350005)National Science Foundation for Young Scientists of China(No.51404118).
文摘The flotation of complex solid–liquid multiphase systems involve interactions among multiple components,the core problem facing flotation theory.Meanwhile,the combined use of multicomponent flotation reagents to improve mineral flotation has become an important issue in studies on the efficient use of refractory mineral resources.However,studying the flotation of complex solid–liquid systems is extremely difficult,and no systematic theory has been developed to date.In addition,the physical mechanism associated with combining reagents to improve the flotation effect has not been unified,which limits the development of flotation theory and the progress of flotation technology.In this study,we applied theoretical thermodynamics to a solid–liquid flotation system and used changes in the entropy and Gibbs free energy of the reagents adsorbed on the mineral surface to establish thermodynamic equilibrium equations that de-scribe interactions among various material components while also introducing adsorption equilibrium constants for the flotation reagents adsorbed on the mineral surface.The homogenization effect on the mineral surface in pulp solution was determined using the chemical potentials of the material components of the various mineral surfaces required to maintain balance.The flotation effect can be improved through synergy among multicomponent flotation reagents;its physical essence is the thermodynamic law that as the number of compon-ents of flotation reagents on the mineral surface increases,the surface adsorption entropy change increases,and the Gibbs free energy change of adsorption decreases.According to the results obtained using flotation thermodynamics theory,we established high-entropy flotation theory and a technical method in which increasing the types of flotation reagents adsorbed on the mineral surface,increasing the adsorption entropy change of the flotation reagents,decreasing the Gibbs free energy change,and improving the adsorption efficiency and stability of the flotation reagents improves refractory mineral flotation.
基金supported by Fundamental Research Projects of Yunnan Province,China(Nos.202101BE070001-009,202301AU070189).
文摘Mineral fulvic acid(MFA)was used as an eco-friendly pyrite depressant to recover chalcopyrite by flotation with the use of the butyl xanthate as a collector.Flotation experiments showed that MFA produced a stronger inhibition effect on pyrite than on chalcopyrite.The separation of chalcopyrite from pyrite was realized by introducing 150 mg/L MFA at a pulp pH of approximately 8.0.The copper grade,copper recovery,and separation efficiency were 28.03%,84.79%,and 71.66%,respectively.Surface adsorption tests,zeta potential determinations,and localized electrochemical impedance spectroscopy tests showed that more MFA adsorbed on pyrite than on chalcopyrite,which weakened the subsequent interactions between pyrite and the collector.Atomic force microscope imaging further confirmed the adsorption of MFA on pyrite,and X-ray photoelectron spectroscopy results indicated that hydrophilic Fe-based species on the pyrite surfaces increased after exposure of pyrite to MFA,thereby decreasing the floatability of pyrite.
基金supported by Yunnan Science and Technology Leading Talent Project(No.202305AB350005)。
文摘Tin is a critical metal for various industries,making its recovery from low-grade cassiterite ores crucial.This study aimed to optimize the flotation recovery of cassiterite using multi-component collector systems.Several collectors were initially selected through micro-flotation tests,leading to the identification of optimal proportions for a four-component collector system(SHA-OHA-SPA-DBIA in a 4:3:2:1 ratio).Molecular dynamics simulations and surface tension tests were used to investigate the micellar behavior of these collectors in aqueous solution.The adsorption characteristics were quantified using microcalorimetry,enabling the determination of collection entropy and changes in Gibbs free energy.The four-component collector system showed the highest entropy change and the most favorable Gibbs free energy,leading to a cassiterite recovery of above 90%at a concentration of 8.0×10^(5)mol/L.Various analytical techniques were employed to systematically characterize the adsorption mechanism.The findings revealed a positive correlation between the adsorption products formed by the multicomponent collectors on the cassiterite surface and the entropy changes.Industrial-scale testing of the high-entropy collector system produced a tin concentrate with an Sn grade of 6.17%and an Sn recovery of 82.43%,demonstrating its substantial potential for practical applications in cassiterite flotation.
基金Project(51464029)supported by the National Natural Science Foundation of ChinaProject(2014M562343)supported by China Postdoctoral Science FoundationProject(KKSY201421110)supported by the Scholar Development Project of Yunnan Province,China
文摘The surface states of pyrite(Fe S2) were theoretically investigated using first principle calculation based on the density functional theory(DFT). The results indicate that both the(200) and(311) surfaces of pyrite undergo significant surface atom relaxation after geometry optimization, which results in a considerable distortion of the surface region. In the normal direction, i.e., perpendicular to the surface, S atoms in the first surface layer move outward from the bulk, while Fe atoms move toward the bulk, forming an S-rich surface. The surface relaxation processes are driven by electrostatic interaction, which is evidenced by a relative decrease in the surface energy after surface relaxation. Such a relaxation process is visually interpreted through the qualitative analysis of molecular mechanics. Atomic force microscopy(AFM) analysis reveals that only sulfur atom is visible on the pyrite surface. This result is consistent with the DFT data. Such S-rich surface has important influence on the flotation properties of pyrite.
基金supported by the National Natural Science Foundation of China(No.52164022).
文摘This study investigated the effect of konjac glucomannan(KGM)on the flotation separation of calcite and scheelite.Micro-flotation tests showed that under the action of 50 mg/L KGM,the floatability of calcite notably decreased,while the impact on scheelite was negligible,resulting in a recovery difference of 82.53%.Fourier transform infrared(FTIR)spectroscopy and atomic force micro-scopy(AFM)analyses indicated the selective adsorption of KGM on the calcite surface.Test results of the zeta potential and UV-visible absorption spectroscopy revealed that KGM prevented the adsorption of sodium oleate on the calcite surface.X-ray photoelectron spec-troscopy(XPS)analysis further confirmed the chemical adsorption of KGM on the calcite surface and the formation of Ca(OH)_(2).The density functional theory(DFT)simulation results were consistent with the flotation tests,demonstrating the strong adsorption perform-ance of KGM on the calcite surface.This study offers a pathway for highly sustainable and cost-effective mineral processing by utilizing the unique properties of biopolymers such as KGM to separate valuable minerals from gangue minerals.
基金supported by the National Natural Science Foundation of China(52066007,22279048)the Major Science and Technology Project of Yunnan Province(202202AG050017).
文摘Molten salt gasification is a promising technology for biomass conversion due to its advantages of superior heat transfer and the ability of utilizing solar energy to reduce carbon emission.In this study,the characteristics of corncob CO_(2)-gasification in molten salt environments is thoroughly investigated,and the approach of introducing Fe_(2)O_(3) as catalyst to enhance the syngas yield is proposed.The results showed that the molten salts significantly promoted the conversion of corncob into gaseous products with very low tar and char yield.Compared to O_(2) and H_(2)O atmospheres,utilizing CO_(2) as gasifying agent enhanced the yield of gaseous products during the corncob gasification,especially the yields of CO and H_(2).The introduction of Fe_(2)O_(3) as a catalyst could further increase the yield of gaseous products and the cold gas efficiency(CGE),and the yield of syngas was increased into 2258.3 ml·g^(−1) with a high CGE of 105.8%in 900℃.The findings evidenced that CO_(2) gasification in the molten salt environment with Fe_(2)O_(3) addition can promote the cracking of tar,increasing the syngas yield significantly.Moreover,the energy required to drive the gasification process was calculated,and the total energy consumption was calculated as 16.83 GJ·t^(−1).The study opened up a new solution for the biomass gasification,exhibiting a great potential in distributed energy or chemical systems.
基金supported by the Yunnan Province Nonferrous Metal Vacuum Metallurgy Top Team[No.202305AS350012]。
文摘Magnesium(Mg),as one of the most abundant elements in earth's crust,is the lightest structural metal with extensive applications across various industries.However,the performance of Mg-based products is highly dependent on their impurity levels,and the lack of high-purity Mg,along with efficient purification method,has posed significant challenge to its widespread industrial adoption.This study investigates the impurity behavior in Mg ingots during the vacuum gasification purification process.Through the analysis of binary phase diagrams,iron(Fe)-based foam material was selected for the filtration and purification of Mg vapor in a vacuum tube furnace.A novel approach combining vacuum gasification,vapor purification,and directional condensation is proposed.The effect of filter pore sizes and filtration temperatures on the efficacy of impurity removal was evaluated.Experimental results demonstrate that Fe-based foam with a pore size of 60 ppi,at a filtration temperature of 773 K,effectively removes impurities such as calcium(Ca),potassium(K),sodium(Na),manganese(Mn),silicon(Si),aluminum(Al),and various oxides,sulfides,and chlorides from the vapor phase.Consequently,high-purity Mg with a purity level exceeding 5N3 was obtained in the condensation zone.
文摘Magnesium(Mg)alloys are widely used lightweight structural materials for automobiles and help reduce carbon emissions.However,their use increases the production of Mg alloy scrap,which is recycled at a much lower rate than aluminum,and its greater complexity poses challenges to existing recycling processes.Although vacuum distillation can be used to recycle Mg alloy scrap,this requires optimizing and maximizing metal recirculation,but there has been no thermodynamic analysis of this process.In this study,the feasibility and controllability of separating inclusions and 23 metal impurities were evaluated,and their distribution and removal limits were quantified.Thermodynamic analyses and experimental results showed that inclusions and impurity metals of separation coefficient lgβ_(i)≤-5,including Cu,Fe,Co,and Ni below 0.001 ppm,could be removed from the matrix.All Zn entered the recycled Mg,while impurities with-1<lgβ_(i)<-5 such as Li,Ca,and Mn severely affected the purity of the recycled Mg during the later stage of distillation.Therefore,an optimization strategy for vacuum distillation recycling:lower temperatures and higher system pressures for Zn separation in the early stage,and the early termination of the recovery process in the later stage or a continuous supply of raw melt can also prevent contamination during recycling.The alloying elements Al and Zn in Mg alloy scrap can be further recovered and purified by vacuum distillation when economically feasible,to maximize the recycling of metal resources.
基金supported by grants from the Beijing Natural Science Foundation,Beijing Economic and Technological Development Zone Innovation Joint Fund(Grant no.L248072).
文摘Immune checkpoint inhibitors have markedly improved outcomes in patients with multiple advanced malignancies.However,their widespread use has markedly increased the incidence of immune-related adverse events(irAEs).irAEs can affect a wide range of organ systems and are characterized by heterogeneous onset,broad toxicity spectra,and complex management requirements,thus ultimately impairing treatment continuation and patient quality of life.This review systematically summarizes the epidemiological features,clinical progression,and current management of irAEs.Existing guidelines largely focus on acute toxicities but have not provided structured strategies for chronic,delayed-onset,or multisystem irAEs.Moreover,clinical practice is hampered by incomplete multidisciplinary collaboration,insufficient training of oncologists,and fragmented treatment pathways,all of which limit the efficacy of irAE management.We propose incorporating irAE management into core oncology training and call for the establishment of comprehensive interdisciplinary frameworks to ensure the standardized long-term use of immunotherapy.
基金supported by the National High-Level Hospital Clinical Research Funding(2022-PUMCH-D-002).
文摘Background:Hypereosinophilia(HE)is a rare disease characterized by an increase in eosinophils.Suplatast tosilate is a selective Th2 cytokine inhibitor.This case report presents the course and prognosis of a patient with hypereosinophilia treated with suplatast tosilate monotherapy.Case presentation:A 41-year-old female patient who complained of“Elevated blood eosinophils were found during physical examination for more than 2 months”visited the Allergy Department.The systematic screening results of parasites,autoantibodies spectrum,tumor markers,peripheral blood morphology analysis,and leukemia fusion gene(FIP1L1-PDGFRα)were all negative.Gastrointestinal endoscopy only indicated mild gastritis.The dust mites and multiple fungal mixtures were weakly positive in intradermal tests.Finally diagnosed HE.After treatment with suplatast tosilate 2 months of 100mg three times daily,the blood eosinophils decreased to normal.Then,maintenance treatment with 50mg three times a day for 3 months.And without recurrence during nearly five years of follow-up.Conclusion:The report indicates that suplatast tosilate can reduce peripheral blood eosinophils levels in patients with HE,and may be a reliable option for individualized treatment of HE.However,there is still no consensus on whether suplatast tosilate can be used as a first-line treatment or as an adjuvant therapy to reduce the corticosteroids dosage for patients with eosinophilia,and further research is needed.
基金supported by the National Key Research and Development Program of China(No.2018YFE0207300)Beijing Natural Science Foundation(No.M23008)+1 种基金the National High Level Hospital Clinical Research Funding(No.2022-PUMCH-B-124)the National High Level Hospital Clinical Research Funding(No.2022-PUMCH-A-057)。
文摘Varicocele(VC)is a common cause of male infertility,yet there is a lack of molecular information for VC-associated male infertility.This study investigated alterations in the seminal plasma metabolomic and lipidomic profiles of infertile male VC patients.Twenty infertile males with VC and twenty-three age-matched healthy controls(HCs)were recruited from Peking Union Medical College Hospital(Beijing,China)between October 2019 and April 2021.Untargeted metabolite and lipid profiles from seminal plasma were analyzed using mass spectrometry.Four hundred and seventy-six metabolites and seventeen lipids were significantly different in infertile male VC patients compared to HCs.The top enriched pathways among these significantly different metabolites are protein digestion and absorption,aminoacyl-transfer RNA(tRNA)biosynthesis,and biosynthesis of amino acids.Different key lipid species,including triglyceride(TG),diacylglycerol(DG),ceramides(Cer),and phosphatidylserine(PS),varied betweenVC and HC groups.The distinct metabolites and lipids were moderately correlated.DL-3-phenyllactic acid is a potential diagnostic biomarker for VC-related male infertility(area under the curve[AUC]=0.893),positively correlating with sperm count,concentration,and motility.Furthermore,DL-3-phenyllactic acid is the only metabolite shared by all four comparisons(VC vs HC,VC-induced oligoasthenospermia[OAS]vs VC-induced asthenospermia[AS],OAS vs HC,and AS vs HC).DL-3-phenyllactic acid significantly decreased in OAS than AS.Metabolite-targeting gene analysis revealed carbonic anhydrase 9(CA9)might be the strongest candidate associated with the onset and severity of VC.The seminal plasma metabolite and lipid profiles of infertile males with VC differ significantly from those of HCs.DL-3-phenyllactic acid could be a promising biomarker.
基金supported by Clinical Research Operating Fund of Central High Level Hospitals(2022-PUMCH-B-088).
文摘Atopic dermatitis(AD)is one of the most common chronic inflammatory skin diseases.It usually develops in childhood and may persist into adulthood.Dupilumab is a fully human monoclonal antibody directed against interleukin-4R-alpha,the common chain of interleukin-4 and interleukin-13 receptors.Dupilumab showed clinical improvements in patients with atopic dermatitis,asthma,and chronic rhinosinusitis and is currently under development for other indications.However,there are many adverse effects reported after dupilumab therapy including local injection site reactions,conjunctivitis,headache,and nasopharyngitis.We report a new case of a 4-year-old child who experienced anaphylaxis after dupilumab injection.In addition to,we summary and disscuss the rare adverse reactions caused by dupilumab injection by searching the literature in pubmed.
基金graciously funded by the Central Government Guidance Fund for Supporting the Local Science and Technology Development(No.XZ202101YD0002C).
文摘Background:Developmental dysplasia of the hip(DDH)is a prevalent pediatric condition with a multifactorial etiology.Its incidence varies geographically,with notably higher rates observed on the Xizang plateau.This study was performed to evaluate the lipidomics signatures associated with DDH by analyzing plasma samples.Methods:Fifty infants were recruited,including 25 diagnosed with DDH and 25 age-matched healthy controls.In addition to plasma samples,comprehensive laboratory test results and medical records were collected for each participant.An untargeted lipidomics profiling approach was employed to identify distinguishing metabolic signatures.Results:Lipidomics profiles differed significantly between patients with DDH and healthy controls.Several differential metabolites were identified,including triacylglycerol(TAG)(17:0/18:1/20:1),TAG(17:0/17:0/17:0),phosphatidylethanolamine(PE)(10:0/26:4),TAG(17:0/18:0/18:0),TAG(16:0/17:0/22:1),TAG(16:0/18:0/22:0),TAG(17:0/19:0/19:0),TAG(13:0/20:0/20:0),TAG(18:0/18:0/22:0),and TAG(16:0/20:0/20:0).The primary lipid species showing differences were TAGs and PE.Conclusions:Distinct shifts in lipidomics profiles were observed in infants with DDH.To the best of our knowledge,this study is the first to explore lipidomics signatures in patients with DDH.The combined assessment of TAG(17:0/18:1/20:1)and TAG(17:0/17:0/17:0)may serve as a potential diagnostic tool for DDH.
基金financially supported by the National Natural Science Foundation of China(No.U2202251)the Yunnan Major Scientific and Technological Projects(No.202202AG050017-02)the Yunnan Fundamental Research Projects(No.202101BE070001-017).
文摘Electroreduction of CO_(2) into beneficial products is integral to attaining carbon neutrality.Herein,we detail a series of anti-perovskite nitrides InNNi_(3−x)V_(x)(x=0,0.2,0.4,0.6,0.8)to be highly effective CO_(2)RR.The InNNi_(2.4)V_(0.6) demonstrated exceptional conversion of CO_(2) to formate,achieving an optimal Faraday efficiency(FE)of 93.6%at−0.754 V versus RHE.It also exhibited a partial current density of 200 mA cm^(−2) at−1.1 V versus RHE,along with remarkable stability in an H-type cell.Electrochemical tests,X-ray absorption fine structure,and theoretical calculations demonstrated that in addition to altering InNNi_(3) electronic structure,V doping results in lattice distortion in NiN_(3) octahedron,increasing the lattice spacing of InNNi_(2.4)V_(0.6)(111)surface,exposing more active sites.This enhances its ability to adsorb the reaction intermediate ^(*)OCHO,thereby facilitating the conversion of CO_(2) into formate.This research offers a viable approach for optimizing an electrocatalyst to convert CO_(2) to valuable products.
基金Project supported by the Major Science and Technology Projects in Yunnan Province(202302AG050005)。
文摘Energy shortages and global warming are driving the focus on the greenhouse gases CH_(4)and CO_(2).The main reason why dry reforming of methane(DRM)has yet to be industrialized is its catalytic tendency to deactivate due to carbon deposition or sintering.Single-atom Ni/CeO_(2)catalysts with suitable metalsupport interactions may provide a new strategy for developing highly active and coking-resistant nickel-based catalysts.In this work,we investigated the properties of the catalytic models of singleatom Ni loaded on CeO_(2)(111),CeO_(2)(110)and CeO_(2)(100),as well as their catalytic DRM performance with the density functional theory method(DFT).The interaction of CeO_(2)with different low-index crystal planes and single-atom Ni can be explained by the anchoring effect of surface O ions on Ni.Adsorption energies,growth patterns of Ni clusters,and migration studies of Ni atoms all indicate that the CeO_(2)(100)surface has the strongest anchoring effect on isolated Ni atoms,followed by the CeO_(2)(110)surface,with the CeO_(2)(111)surface being the weakest,Methane activation studies have shown that the activation ability of Ni_(1)/CeO_(2)(110)for methane strongly depends on the coordination environment of Ni,By contrast,methane activation by Ni on Ni_(1)/CeO_(2)(111)exhibits better activity and stability.Moreover,the Ni—CeO_(2)interaction correlates well with the DRM reaction performance.Interactions that are too strong anchor Ni atoms well but are not optimal for DRM activity.Ni_(1)/CeO_(2)(110)has relatively moderate interactions,promotes the^(*)CH_(4)→^(*)CH process,and has good resistance to carbon deposition.The metalsupport interaction-DRM reactivity(or stability)relationship is vital for the design of"super"highactivity and high-stability DRM catalysts.
基金supported by USTB Institute for International People-to-People Exchange in Mining,Metallurgy and Metals Industries(No.FRF-IPPE-2404)Scientific Research Platform Construction Fund for the Introduction of High-Level Talents at Kunming University of Science and Technology(No.CA25073M246A).
文摘The superconducting high gradient magnetic separation(S-HGMS)technology can be used to effectively extract silica from iron ore tailings(IOTs).However,particle agglomeration in strong magnetic fields poses a challenge in achieving optimal performance.In this study,we investigated the agglomeration of IOT particles and the mechanisms for its inhibition through surface analysis,density functional theory(DFT),and extended Derjaguin-Landau-Verwey-Overbeek(EDLVO)theory.Hematite was found to exhibit the highest magnetic moment among the minerals present in IOTs,making it particularly prone to magnetic agglomeration.The addition of the dispersant SDSH into the slurry was essential in promoting the dispersion of IOT particles during the S-HGMS process.This dispersant hydrolyzed to form HPO_(4)^(2-)and RSO_(3)^(-)groups in the solution,which then chemically adsorbed onto the metal ions exposed on the surfaces of non-quartz particles,increasing interparticle electrostatic repulsion.Furthermore,the RSO_(3)^(-)groups physically adsorbed onto the surface of quartz particles,resulting in strong steric repulsion and enhancing the hydrophilicity of the particle surfaces,thereby inhibiting magnetic agglomeration between the particles.Under optimal conditions,the SiO_(2)grade of the obtained high-grade silica powder increased from an initial value of 76.32%in IOTs to 97.42%,achieving a SiO_(2)recovery rate of 54.81%,which meets the requirements for quartz sand used in glass preparation.This study provides valuable insights into the magnetic agglomeration of IOT particles and its inhibition while providing a foundation for regulating S-HGMS processes.
基金Supported by Yunnan Fundamental Research Projects(Nos.202301AT070469,202301AT070275)Supported by Yunnan Major Scientific and Technological Projects(No.202202AG050002).
文摘Smelting with oxygen bottom blowing is one of the main methods used in the frame of copper pyrometallurgy.With this approach,feed materials and oxygen-enriched air are introduced in reversed order to enhance multiphaseflow within the furnace.Understanding the flow structure and temperature distribution in this setup is crucial foroptimizing production.In this study,gas-liquid interactions,and temperature profiles under varying air-injectionconditions are examined by means of numerical simulation for a 3.2 m×20 m furnace.The results indicate that thehigh-velocity regions are essentially distributed near the lance within the reaction region and the flue gas outlet,while low-velocity regions are located close to the furnace walls on both side of the reaction region.Dead regionsappear in the sedimentation region,with gas velocities surpassing those of the molten phase.As the injection rateincreases from 0.50 to 0.80 Nm3/s,the stabilization time of the average liquid surface velocity decreases from 2.6 sto 1.9 s,exhibiting a similar trend to the gas holdup.During stabilization,the average liquid surface velocity risesfrom 0.505 to 0.702 m/s.The average turbulent kinetic energy(TKE)of the fluid in the molten bath increases from0.095 to 0.162 m^(2)/s^(2).The proportion of the area distribution with TKE greater than 0.10 m^(2)/s^(2) and the gas holdupat steady state both rise with an increase in the injection quantity.The maximum splashing height of the melt growsfrom approximately 0.756 to 1.154 m,with the affected area expanding from 14.239 to 20.498 m^(2).Under differentworking conditions with varying injection quantities,the average temperature changes in melt zone and flue gaszone of the furnace are small.The temperature in the melt and in the flue-gas zone spans the interval 1200℃–1257℃,and 1073℃–1121℃,respectively.The temperature distribution of the melt and flue gas reveals a patterncharacterized by elevated temperatures in the reaction zone,gradually transitioning to lower temperatures in thesedimentation region.
