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Efficient recovery of tungsten from scheelite concentrates using a sulfur-phosphorus mixed acid leaching system

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Tungsten 2024年第4期6卷 821-832页

作者： Jiang-Tao Li Li-Li Gao Zhong-Wei Zhao Xu-Heng Liu Xing-Yu Chen School of Metallurgy and Environment Central South University Key Laboratory of Hunan Province for Metallurgy and material processing of Rare Metals

In recent years,a new process for leaching scheelite concentrates with sulfur-phosphorus mixed acid has been successfully *** process suffers from the elimination of the retarding effect of calcium sulfate,the selective extraction of tungsten from the H3PW12O40-H2SO4-H3PO4mixture solution,and the removal of introduced ***,in this paper,we investigated the inhibition measures of a calcium sulfate-blocking membrane,the selective extraction of tungsten by ion exchange,and the removal of phosphorus by the magnesium ammonium salt *** results showed that the addition of calcium sulfate whisker seeds and a higher H3PO4concentration inhibited spontaneous diffuse nucleation,promoted crystal growth,and avoided the formation of a dense blocking *** 98 wt.% of the scheelite concentrate was digested by *** selective adsorption of PW12O403-was realized using D301 resin,and the extraction efficiency of tungsten exceeded 99.9%.After desorption with ammonia water,PW12O403-was depolymerized into WO42-and PO43-.99.9 wt.% of phosphorus was removed in the form of MgNH4PO4by the magnesium ammonium salt method,and the residual phosphorus concentration in the solution was lower than 10 mg·*** purification,the highest-grade ammonium paratungstate product was prepared by evaporative crystallization.

关键词： Calcium sulfate Ion exchange Scheelite concentrates Sulfur-phosphorus mixed acid Tungsten

Mussel-inspired Methacrylic Gelatin-dopamine/Ag Nanoparticles/Graphene Oxide Hydrogels with Improved Adhesive and Antibacterial Properties for Applications as Wound Dressings

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Journal of Wuhan University of Technology(materials Science) 2024年第2期39卷 512-521页

作者：宿正楠 HU Yanru MENG Lihui OUYANG Zhiyuan LI Wenchao ZHU Fang XIE Bin 吴庆知 State Key Laboratory of Advanced Technology for materials Synthesis and processing Biomedical Material and Engineering Center of Hubei ProvinceWuhan University of TechnologyWuhan 430070China

A novel strategy was developed to prepare the methacrylic gelatin-dopamine(GelMA-DA)/Ag nanoparticles(NPs)/graphene oxide(GO) composite hydrogels with good biocompatibility,mechanical properties,and antibacterial ***-inspired DA was utilized to modify the GelMA molecules,which imparts good adhesive performance to the ***,interfacial enhancer,not only improves mechanical properties of the hydrogels,but also provides anchor sites for loading Ag NPs through numerous oxygencontaining functional groups on the *** experimental results show that the GelMA/Ag NPs/GO hydrogels have good biocompatibility,and exhibit a swelling rate of 202±16%,the lap shear strength of 147±17 kPa,and compressive modulus of 136±53 kPa,in the case of the Ag NPs/GO content of 2 mg/*** activity of the hydrogels against both gram-negative and gram-positive bacteria is dependent on the Ag NPs/GO content derived from the release of Ag^(+).Furthermore,the GelMA/Ag NPs/GO hydrogels possess good adhesive ability,which is resistant to highly twisted state when stuck on the surface of *** results demonstrate promising potential of the GelMA-DA/Ag NPs/GO hydrogels as wound dressings for biomedical applications in clinical and emergent treatment.

关键词： GelMA dopamine,graphene oxide adhesion antibacterial ability

A molecular insight into coke formation process of vacuum residue in thermal cracking reaction

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Petroleum Science 2024年第3期21卷 2130-2138页

作者： Ji-Guang Li Xin Guo Huan-Di Hou Heavy Oil processing department Sinopec Research Institute of Petroleum Processing Co.LtdBeijing100083China

Understanding the coking behaviors has been considered to be really essential for developing better vacuum residue processing technologies.A battery of thermal cracking tests of typical vacuum residue at 410℃ with various reaction time were performed to evaluate the coke formation *** total yields of ideal components including naphtha,atmospheric gas oil(AGO)and vacuum gas oil(VGO)of thermal cracking reactions increased from 10.89%to 40.81%,and the conversion ratios increased from8.05%to 43.33%with increasing the reaction time from 10 to 70 *** asphaltene content increased from 12.14%to a maximum of 22.39%and then decreased,and this maximum of asphaltene content occurred at the end of the coking induction *** asphaltenes during the coking induction period,at the end and after coking induction period of those tested thermal cracking reactions were characterized to disclose the structure changing rules for coke formation process,and the coke formation pathways were discussed to reveal the coke formation process at molecular level.

关键词： Vacuum residue Thermal cracking Asphaltene Coking induction period Sulfur Nitrogen

Tuning the solubility of polysulfides for constructing practical lithium-sulfur battery

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Journal of Energy Chemistry 2024年第8期95卷 611-617,I0013页

作者： Jiapeng Li Jianlong Cong Haijin Ji Ting Shi Lixia Yuan Yunhui Huang State Key Laboratory of material processing and Die&Mold Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074HubeiChina

Li-S batteries are regarded as one of the most promising candidates for next-generation battery systems with high energy density and low ***,the dissolution-precipitation reaction mechanism of the sulfur(S)cathode enhances the kinetics of the redox processes of the insulating sulfu r,which also arouses the notorious shuttle effect,leading to serious loss of S species and corrosion of Li *** get a balance between the shuttle restraining and the kinetic property,a combined strategy of electrolyte regulation and cathode modification is proposed via introducing 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoroprpyl ether(HFE)instead of 1,2-dimethoxyethane(DME),and SeS_(7)instead of S_*** introduction of HFE tunes the solvation structure of the LiTFSI and the dissolution of intermediate polysulfides with Se doping(LiPSSes),and optimize the interface stability of the Li anode *** minor Se substitution compensates the decrease in kinetic due to the decreased solubility of *** this way,the Li-SeS_(7)batteries deliver a reversible capacity of 1062 and 1037 mAh g^(-1)with 2.0 and 5.5 mg SeS_(7)cm^(-2)loading condition,***,an electrolyte-electrode loading model is established to explain the relationship between the optimal electrolyte and cathode *** makes more sense to guide the electrolyte design for practical Li-S batteries.

关键词： Li-S batteries Lithium polysulfides Solubility Shuttle effect Interface Se doping

Unraveling the incompatibility mechanism of ethylene carbonate-based electrolytes in sodium metal anodes

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Journal of Energy Chemistry 2024年第7期94卷 560-567页

作者： Daomin Qin Fangyuan Cheng Meilian Cao Feiyang Yan Qian Wang Chun Fang Jiantao Han State Key Laboratory of material processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan430074HubeiChina

Ethylene carbonate(EC)is widely used in lithium-ion batteries due to its optimal overall performance with satisfactory conductivity,relatively stable solid electrolyte interphase(SEI),and wide electrochemical *** is also the most widely used electrolyte solvent in sodium ion ***,compared to lithium metal,sodium metal(Na)shows higher activity and reacts violently with EC-based electrolyte(NaPF_(6)as solute),which leads to the failure of sodium metal batteries(SMBs).Herein,we reveal the electrochemical instability mechanism of EC on sodium metal battery,and find that the com-bination of EC and NaPF_(6) is electrically reduced in sodium metal anode during charging,resulting in the reduction of the first coulombic efficiency,and the continuous consumption of electrolyte leads to the cell *** address the above issues,an additive modified linear carbonate-based electrolyte is provided as a substitute for EC based ***,ethyl methyl carbonate(EMC)and dimethyl carbon-ate(DMC)as solvents and fluoroethylene carbonate(FEC)as SEI-forming additive have been identified as the optimal solvent for NaFP_(6)based electrolyte and used in Na_(4)Fe_(3)(PO_(4))_(2)(P_(2)O_(7))/Na *** batter-ies exhibit excellent capacity retention rate of about 80%over 1000 cycles at a cut-off voltage of 4.3 V.

关键词： Na metal batteries Ethylene carbonate decomposition Na_(4)Fe_(3)(PO_(4))_(2)(P_(2)O_(7))cathode Interface engineering Ethylene carbonate-free electrolyte

All-fluorinated electrolyte for non-flammable batteries with ultra-high specific capacity at 4.7 V

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Green Energy & Environment 2024年第10期9卷 1601-1609页

作者： Zhe Wang Zhuo Li Jialong Fu Sheng Zheng Rui Yu Xiaoyan Zhou Guanjie He Xin Guo State Key Laboratory of material processing and Die&Mould Technology Laboratory of Solid State IonicsSchool of Materials Science and EngineeringHuazhong University of Science and Technology Electrochemical Innovation Lab Department of Chemical EngineeringUniversity College London

Li metal batteries （LMBs） with Li Ni0.8Mn0.1Co0.1O2（NMC811） cathodes could release a specific energy of >500 Wh kg-1by increasing the charge ***,high-nickel cathodes working at high voltages accelerate degradations in bulk and at interfaces,thus significantly degrading the cycling lifespan and decreasing the specific ***,we rationally design an all-fluorinated electrolyte with addictive tri（2,2,2-trifluoroethyl） borate （TFEB）,based on 3,3,3-fluoroethylmethylcarbonate （FEMC） and fluoroethylene carbonate （FEC）,which enables stable cycling of high nickel cathode (Li Ni0.8Co0.1Mn0.1O2,NMC811) under a cut-off voltage of 4.7 V in Li metal *** electrolyte not only shows the fire-extinguishing properties,but also inhibits the transition metal dissolution,the gas production,side reactions on the cathode ***,the NMC811||Li cell demonstrates excellent performance by using limited Li and high-loading cathode,delivering a specific capacity>220 m A h g-1,an average Coulombic efficiency >99.6% and capacity retention >99.7% over 100 cycles.

关键词： Fluorinated electrolyte Li metal batteries Solid electrolyte interphase Cathode electrolyte interphase Coulombic efficiency

Electrochemical anodic oxidation assisted fabrication of memristors

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International Journal of Extreme Manufacturing 2024年第3期6卷 250-272页

作者： Shuai-Bin Hua Tian Jin Xin Guo School of materials Science and Engineering State Key Laboratory of Material Processing and Die&Mould TechnologyHuazhong University of Science and TechnologyWuhan 430074People’s Republic of China

Owing to the advantages of simple structure,low power consumption and high-density integration,memristors or memristive devices are attracting increasing attention in the fields such as next generation non-volatile memories,neuromorphic computation and data ***,the deposition of memristive films often requires expensive equipment,strict vacuum conditions,high energy consumption,and extended processing *** contrast,electrochemical anodizing can produce metal oxide films quickly(e.g.10 s) under ambient *** means of the anodizing technique,oxide films,oxide nanotubes,nanowires and nanodots can be fabricated to prepare *** film thickness,nanostructures,defect concentrations,etc,can be varied to regulate device performances by adjusting oxidation parameters such as voltage,current and *** memristors fabricated by the anodic oxidation technique can achieve high device consistency,low variation,and ultrahigh yield *** article provides a comprehensive review of the research progress in the field of anodic oxidation assisted fabrication of ***,the principle of anodic oxidation is introduced;then,different types of memristors produced by anodic oxidation and their applications are presented;finally,features and challenges of anodic oxidation for memristor production are elaborated.

关键词： anodic oxidation anodized aluminium oxide memristor resistive switching electrical properties

Effect of Microstructural Characteristics on Fracture Toughness in Direct Energy Deposited Novel Ti-6Al-4V-1Mo Alloy

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 119-131页

作者： Chao Xia Kexin Zhao Xin Zhou Yuqi He Panpan Gao Hengxin Zhang Guangrui Gao Fengying Zhang Hua Tan School of material Science and Engineering Chang’an UniversityXi’an710064China Science and Technology on Plasma Dynamics Laboratory Air Force Engineering UniversityXi’an710038China State Key Laboratory of Solidification processing Northwestern Polytechnical UniversityXi’an710072China Surface material Protection Co. LtdXi’an710018China

Meeting the damage tolerance requirements for engineering-grade titanium alloys pose a significant challenge in achieving high fracture toughness in direct energy deposition(DED)titanium *** work primarily investigated the relationship between the microstructure and the fracture toughness of DED new Ti-6Al-4V-1Mo *** types of microstructures were designed via two process strategies:high-line energy density(HE)and low-line energy density(LE).Relative to LE samples,HE samples possess larger-sized microstructural characteristics(coarser grain boundaryα(α_(GB)),largerαcolonies,and coarserαlaths).Lessα/βphase boundaries were formed by coarserαlaths in the HE samples,increasing the movement of dislocations,resulting in tensile strength decreasing from 1007.1 MPa(LE)to 930.8 MPa(HE)and elongation increasing from 10.8%(LE)to 15.7%(HE).Also,HE samples exhibited an excellent fracture toughness of 114.0 MPa m^(1/2),significantly higher than that of LE samples(76.8 MPa m^(1/2)).An analysis of crack propagation paths was conducted to investigate the factors contributing to *** primary factor enhancing toughness is the frequent obstruction of cracks by coarseαGB and largeαcolonies in HE ***,the pretty large-angle deflections induced by the superposition effect of coarseαGB and largeαcolonies play a vital of significant *** factors induced the long and tortuous high-energy pathways,which resulted in ultimately improved fracture *** discovered microstructural toughening mechanisms can serve as a reference for future studies involving titanium alloys,offering insights on how to enhance fracture toughness by achieving similar characteristics.

关键词： Direct energy deposition Ti-6Al-4V-1Mo Tensile properties Fracture toughness Crack propagation

Effect of solidification cooling rate on microstructure and tribology characteristics of Zn-4Si alloy

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International Journal of Minerals,Metallurgy and materials 2024年第2期31卷 362-373页

作者： F.Akbari M.Golkaram S.Beyrami G.Shirazi K.Mantashloo R.Taghiabadi M.Saghafi Yazdi I.Ansarian department of Metallurgy and material Science Imam Khomeini International University(IKIU)Qazvin ***Iran

The main objective of this work was to modify the microstructure and enhance the tribological properties of a new Zn-4Si al-loy through a high solidification cooling rate(SCR).According to the results,by increasing the SCR from 2.0 to 59.5℃/s the average size of primary Si particles and that of the grains reduced from 76.1 and 3780μm to less than about 14.6 and 460μm,***-ing the SCR also enhanced the microstructural homogeneity,decreased the porosity content(by 50%),and increased the matrix hardness(by 36%).These microstructural changes enhanced the tribological *** instance,under the applied pressure of 0.5 MPa,an in-crease in the SCR from 2.0 to 59.5℃/s decreased the wear rate and the average friction coefficient of the alloy by 57%and 23%,*** wear mechanism was also changed from the severe delamination,adhesion,and abrasion in the slowly-cooled alloy to the mild tribolayer delamination/abrasion in the high-cooling-rate-solidified sample.

关键词： zinc-silicon alloy primary silicon solidification cooling rate tribology sliding wear