Based on the pipe transportation of paste-like backfilling system of a certain deep coal mine,its dynamics process was simulated and analyzed.A two-dimensional dynamic model of extraordinary deep and lone pipe was bui...Based on the pipe transportation of paste-like backfilling system of a certain deep coal mine,its dynamics process was simulated and analyzed.A two-dimensional dynamic model of extraordinary deep and lone pipe was built by GAMBIT,on the basis of which the simulation was done by implicit solver of FLUENT 2ddp.The results show that hydraulic loss of pipe transportation is less than the pressure produced by gravity,which means the backfilling material can flow by itself.When the inlet velocity is 3.2 m/s,the maximum velocity of 4.10 m/s is at the elbow and the maximum velocity in the horizontal pipe is 3.91 m/s,which can both meet the stability requirement.The results of the simulation are proved to be reliable by the residual monitor plotting of related parameter,so it can be concluded that the system of pipe transportation is safe.展开更多
To make backfilling body meet strength requirement,physical-chemical evaluation and proportioning tests were conducted on several backfilling materials.Jigging sands,#32.5 cement and fly ash were determined as backfil...To make backfilling body meet strength requirement,physical-chemical evaluation and proportioning tests were conducted on several backfilling materials.Jigging sands,#32.5 cement and fly ash were determined as backfilling aggregate,binding material and modified material,respectively.An optimized proportion of backfilling materials with a solid mass fraction of 78%and cement:fly ash:jigging sands mass ratio of 1:2:14,was suggested to Jiangan Pyrite Mine,China.The slurry made by optimized proportion produced obvious shear thinning phenomena,and was confirmed as paste-like slurry.To analyze its rheological characteristics,L-type pipeline test and Haake VT550 rotational viscometer test were conducted.Bingham and Casson fluid models were applied to several paste-like slurry samples to simulate flow and stress states;Casson fluid model was proved to have better simulation effect on paste-like slurry with shear thinning phenomena;rheological parameters of backfilling slurry made by suggested proportion were measured.Initial yield stress,average apparent viscosity and limiting viscosity are 55.35 Pa,1.216 Pa-s and 0.48 Pa-s,respectively.Compared with Bingham fluid model,Casson fluid model has a better simulation effect on paste-like slurry with shear thinning phenomena,through calculating the residual standard deviations.展开更多
A paste-like self-flowing pipeline transportation backfilling technology with coal gangue as aggregate is proposed to remove the potential damage caused by coal gangue piles. As well, the difficult problems of recover...A paste-like self-flowing pipeline transportation backfilling technology with coal gangue as aggregate is proposed to remove the potential damage caused by coal gangue piles. As well, the difficult problems of recovering high quality safety coal pillars and deep mining of the Suncun Coal Mine （SCM）, Xinwen Coal Group, Shandong are resolved. The physical-chemical properties of coal gangue, optimized proportion of materials, backfilling system and craft in the SCM were studied in the laboratory and then an industrial test was carried out on high quality coal pillars under a town. The results show that finely crushed kaolinized and fresh gangue with granularity less than 5 mm can be used as aggregate with fly ash to replace part of the cement and a composite water reducer as an additive, accounting for 1.0%-1.5% of the total amount of cement and fly ash. The recommended proportion is l（cement）：4（fly ash）： 15（coal gangue）, with a mass fraction of 72%-75%, rheoiogical paste-like properties and a strength of more than 0.7 MPa at 7 d. The sequence of adding cement, fly ash, water reducer and then coal gangue ensures that the suspended state of the slurry, reducing the wear and jam of pipelines. The working face is advancing continuously by the alternating craft of building block walls with coal gangue and backfilling mined-out gobs with paste-like slurry. The recovery rate is as high as 90% with a backfilling cost of 36.9 YuarffL good utilization of coal gangue and no subsidence on the surface. This technology provides a good theoretical basis and application experience for coal mines, cement backfilling with paste-like slurry.展开更多
The experiments, which include the complete stress-strain curves, triaxial compressive loading history and the main factors affecting the compressive strength of the material, were made to research the mechanical prop...The experiments, which include the complete stress-strain curves, triaxial compressive loading history and the main factors affecting the compressive strength of the material, were made to research the mechanical properties of paste-like fill material. The results show that the material still has a relatively high load-bearing capacity after yielding. From the view of the backfill strength, the suitable content of the fine particles in the aggregates is 20%, the curing temperature of backfill slurry is about 20 centigrade degrees or higher. The backfill strength can reach 2.5-3.6 MPa when the binder dosage is 5%-8%. It can meet the needs for mining with backfill.展开更多
Utilizing phosphorus tailings as the raw material for foam concrete is a key approach to achieving sustainable and efficient resource utilization.During the preparation of phosphorus tailings-based foam concrete,slurr...Utilizing phosphorus tailings as the raw material for foam concrete is a key approach to achieving sustainable and efficient resource utilization.During the preparation of phosphorus tailings-based foam concrete,slurry performance is critical to the successful production.Phosphorus tailings,cement and microsilica were used to prepare foam concrete slurry in this study.A rheometer was employed as a test tool to measure the variation of linear viscoelastic zone(LVR),viscosity,and yield stress of the slurries with different cement contents.The results indicate that the phosphorus tailings-cement-microsilica slurry exhibits shear-thinning properties,which aligns well with the Herschel-Bulkley model,showing a high degree of correlation.As the cement content increases,the energy storage modulus of the slurry rises,and the LVR length shows a nonlinear trend.The LVR reaches its maximum length of 0.04%when the cement content is 6 mass%or 8 mass%.The increment of the cement content leads to a more intricate internal network structure,which hinders the reconstruction rate of the flocculated structure after high-shear deformation.展开更多
The multipath application of green resources needs to be realised under the carbon neutrality goal.Worldwide,biomass is a resource in urgent need of treatment.In this paper,corn stover biomass(YM)or biochar with diffe...The multipath application of green resources needs to be realised under the carbon neutrality goal.Worldwide,biomass is a resource in urgent need of treatment.In this paper,corn stover biomass(YM)or biochar with different particle sizes(YMF or YMX)was added during the preparation of coal-water slurry to investigate its effect on the performance of coal-water slurry and the micro-mechanism.The results showed that the fixed viscosity concentration of coal-water slurry(CYWS)with YM was only 47.42%,and the flowability was 49.9 mm,which made the slurry performance poor.The fixed viscosity concentration of coal-water slurry(CFWS)blended with YMF and coal-water slurry(CXWS)blended with YMX increased by 10.41%and 14.24%,respectively,compared with CYWS.Meanwhile,CXWS had the lowest thixotropy and yield stress,with a yield stress of only 16.13 Pa,which was 77.31 Pa lower than that of CYWS.This indicates that YMX treated by charring and milling is more favorable to be blended with coal to prepare coal-water slurry.This is due to the enhanced hydrophilicity and electronegativity of YMX.The enhanced hydrophilicity reduces the tendency to form three-dimensional networks in coal-water slurry,while the enhanced electronegativity improves the electrostatic repulsion between particles,which is beneficial to the dispersion of particles.In the subsequent EDLVO analyses,the same idea was proved.展开更多
To fundamentally alleviate the excavation chamber clogging during slurry tunnel boring machine(TBM)advancing in hard rock,large-diameter short screw conveyor was adopted to slurry TBM of Qingdao Jiaozhou Bay Second Un...To fundamentally alleviate the excavation chamber clogging during slurry tunnel boring machine(TBM)advancing in hard rock,large-diameter short screw conveyor was adopted to slurry TBM of Qingdao Jiaozhou Bay Second Undersea Tunnel.To evaluate the discharging performance of short screw conveyor in different cases,the full-scale transient slurry-rock two-phase model for a short screw conveyor actively discharging rocks was established using computational fluid dynamics-discrete element method(CFD-DEM)coupling approach.In the fluid domain of coupling model,the sliding mesh technology was utilized to describe the rotations of the atmospheric composite cutterhead and the short screw conveyor.In the particle domain of coupling model,the dynamic particle factories were established to produce rock particles with the rotation of the cutterhead.And the accuracy and reliability of the CFD-DEM simulation results were validated via the field test and model test.Furthermore,a comprehensive parameter analysis was conducted to examine the effects of TBM operating parameters,the geometric design of screw conveyor and the size of rocks on the discharging performance of short screw conveyor.Accordingly,a reasonable rotational speed of screw conveyor was suggested and applied to Jiaozhou Bay Second Undersea Tunnel project.The findings in this paper could provide valuable references for addressing the excavation chamber clogging during ultra-large-diameter slurry TBM tunneling in hard rock for similar future.展开更多
In this work,the influences of surface layer slurry at different temperatures(10℃,14℃,18℃,22℃)on wax patterns deformation,shrinkage,slurry coating characteristics,and the surface quality of the casting were invest...In this work,the influences of surface layer slurry at different temperatures(10℃,14℃,18℃,22℃)on wax patterns deformation,shrinkage,slurry coating characteristics,and the surface quality of the casting were investigated by using a single factor variable method.The surface morphologies of the shell molds produced by different temperatures of the surface(first)layer slurries were observed via electron microscopy.Furthermore,the microscopic composition of these shell molds was obtained by EDS,and the osmotic effect of the slurry on the wax patterns at different temperatures was also assessed by the PZ-200 Contact Angle detector.The forming reasons for the surface cracks and holes of thick and large ZTC4 titanium alloy by investment casting were analyzed.The experimental results show that the surface of the shell molds prepared by the surface layer slurry with a low temperature exhibits noticeable damage,which is mainly due to the poor coating performance and the serious expansion and contraction of wax pattern at low temperatures.The second layer shell material(SiO_(2),Al_(2)O_(3))immerses into the crack area of the surface layer,contacts and reacts with the molten titanium to form surface cracks and holes in the castings.With the increase of the temperature of surface layer slurry,the damage to the shell surface tends to weaken,and the composition of the shell molds'surface becomes more uniform with less impurities.The results show that the surface layer slurry at 22℃is evenly coated on the surface of the wax patterns with appropriate thickness,and there is no surface shell mold rupture caused by sliding slurry after sand leaching.The surface layer slurry temperature is consistent with the wax pattern temperature and the workshop temperature,so there is no damage of the surface layer shell caused by expansion and contraction.Therefore,the shell mold prepared by the surface layer slurry at this temperature has good integrity,isolating the contact between the low inert shell material and the titanium liquid effectively,and the ZTC4 titanium alloy cylinder casting prepared by this shell mold is smooth,without cracks and holes.展开更多
Traditional pyrometallurgical and hydrometallurgical methods to extract bismuth from sulfide ores face problems such as high cost,low-concentration SO_(2)generation,and long process time.In this study,the cyclone tech...Traditional pyrometallurgical and hydrometallurgical methods to extract bismuth from sulfide ores face problems such as high cost,low-concentration SO_(2)generation,and long process time.In this study,the cyclone technology and slurry electrolysis method were combined.The bismuth sulfide ore was dissolved directly at the anode,while the high purity bismuth was deposited efficiently at the cathode under the advantages of the two methods.The short process and high-efficiency extraction of bismuth sulfide ore were realized,and the pollution of low-concentration SO_(2)was avoided.Then,the effects of several crucial experimental conditions(current density,reaction time,temperature,pH,liquid-solid ratio,and circulation flow rate)on the leaching efficiency and recovery efficiency of bismuth were investigated.The leaching and electrowinning mechanisms during the recovery process were also analyzed according to the research results of this paper to better understand the cyclone slurry electrolysis process.The experimental results showed that 95.19%bismuth was leached into the acid solution in the anode area under optimal conditions,and the recovery efficiency and purity of bismuth on the cathode reached 91.13%and 99.26%,respectively,which were better than those by the traditional hydrometallurgy recovery process.展开更多
The influences of reaction temperature,duration,pressure,and catalyst concentration on the molecular transformation of residual slurry phase hydrocracking process were investigated.The molecular composition of the het...The influences of reaction temperature,duration,pressure,and catalyst concentration on the molecular transformation of residual slurry phase hydrocracking process were investigated.The molecular composition of the heteroatom compounds in the residue feedstock and its upgrading products were characterized using high-resolution Orbitrap mass spectrometry coupled with multiple ionization methods.The simultaneous promotion of cracking and hydrogenation reactions was observed with increasing of the reaction temperature and time.Specifically,there was a significant increase in the cracking degree of alkyl side chain,while the removal of low-condensation sulfur compounds such as sulfides and benzothiophenes was enhanced.In particular,the cracking reactions were more significantly facilitated by high temperatures,while an appropriately extended reaction time can result in the complete elimination of the aforementioned sulfur compounds with a lower degree of condensation.Under conditions of low hydrogen pressure and catalyst concentration,the products still exhibit a high relative abundance of easily convertible compounds such as sulfoxides,indicating a significant deficiency in the effectiveness of hydrogenation.The hydrogen pressure exhibits an optimal value,beyond which further increments have no effect on the composition and performance of the liquid product but can increase the yield of the liquid product.At significantly high catalyst concentration,the effect of desulfurization and deoxidation slightly diminishes,while the aromatic saturation of highly condensed compounds was notably enhanced.This hydrogenation saturation effect cannot be attained through manipulation of other operational parameters,thereby potentially benefiting subsequent product processing and utilization.This present study demonstrates a profound comprehension of the molecular-level residue slurry phase hydrocracking process,offering not only specific guide for process design and optimization but also valuable fundamental data for constructing reaction models at the molecular level.展开更多
Investment casting shell moulds are widely applied to cast alloys, but how to efficiently form a hierarchical porous structure inside the wall is an innovation and challenge. In this research, porous shell moulds with...Investment casting shell moulds are widely applied to cast alloys, but how to efficiently form a hierarchical porous structure inside the wall is an innovation and challenge. In this research, porous shell moulds with three infill patterns(rectilinear, grid, and honeycomb) were prepared using bauxite slurry and slurry extrusionbased additive manufacturing technology, and the effects of infill patterns on the properties were evaluated. The hierarchical pores inside the wall are composed of the macropores formed by infills and the micropores among bauxite particles. Different infill patterns result in changes in distribution and shape of pores, thereby affecting the properties of the shell moulds. The honeycomb pattern has more comprehensive advantages compared to the other two infill patterns. The samples prepared with the honeycomb pattern exhibit the highest bending strength(11.62 MPa) and porosity(41.6%), as well as good heat-transfer ability, with an average shrinkage rate within 2.0%. This work provides an attractive feasibility for fabricating shell moulds with hierarchical porous walls.展开更多
Erosion in slurry pumps presents a persistent challenge in industrial applications.This study examines the erosion of the static components of a 150ZJ-C42 centrifugal slurry pump,currently in operation at a beneficiat...Erosion in slurry pumps presents a persistent challenge in industrial applications.This study examines the erosion of the static components of a 150ZJ-C42 centrifugal slurry pump,currently in operation at a beneficiation plant,under varying particle conditions.Utilizing high-precision three-dimensional reverse engineering,the pump’s flow passage geometry was reconstructed to facilitate detailed erosion analysis.Focusing on the front and rear baffles of the pump chamber,as well as the volute,erosion patterns were analyzed for different particle volume concentrations and sizes.The results reveal that the highest erosion damage consistently occurs near the volute tongue,with wear being most severe in regions adjacent to the partition plate near the rear cover.Erosion damage intensity in this area correlates positively with particle diameter.Notably,the average erosion rate in the volute surpasses that of the front and rear chamber liners,reaching a value as high as 6.03×10^(-7)kg·m^(-2)·s^(-1)at a particle concentration of 9%and diameter of 0.1 mm,adversely impacting pump stability.For the pump chamber baffles,increased erosion is observed at a particle diameter of 0.05 mm under constant volume concentration conditions,while higher particle concentrations exacerbate localized erosion.展开更多
We examined the mechanical strength and microscopic property effects of bottom ash(BA)recycled concrete made by partially substituting natural aggregates made from three industrial wastes,fly ash(FA),silica fume(SF),f...We examined the mechanical strength and microscopic property effects of bottom ash(BA)recycled concrete made by partially substituting natural aggregates made from three industrial wastes,fly ash(FA),silica fume(SF),furnace slag(FS),and cement after BA was treated with slurry to improve the properties of BA and increase its utilisation.The compressive,flexural,splitting tensile strengths,and drying shrinkage test of the recycled concrete from BA were tested at the macroscopic level,and the specimens were analyzed by scanning electron microscopy(SEM)at the microscopic level.The experimental results show that the slurry treatment of BA results in a corresponding improvement in the macroscopic and microscopic properties of the obtained slurry-bound BA aggregates.The synergistic effect of FA and SF can better fill the pores on the surface of BA,which in turn can better improve the properties of recycled concrete.This study provides a theoretical support for improving the properties of BA and promoting its utilisation as a resource.展开更多
We demonstrate for the first time the critical influence of binder molecular weight on the performance of slurry-cast lithium nickel manganese cobalt oxide(NMC)cathodes in sulfide-based all-solid-state batteries(SSBs)...We demonstrate for the first time the critical influence of binder molecular weight on the performance of slurry-cast lithium nickel manganese cobalt oxide(NMC)cathodes in sulfide-based all-solid-state batteries(SSBs).SSBs are increasingly recognized as a safer and potentially more efficient alternative to traditional Li-ion batteries,owing to the superior ionic conductivities and inherent safety features of sulfide solid electrolytes.However,the integration of high-voltage NMC cathodes with sheet-type sulfide solid electrolytes presents significant fabrication challenges.Our findings reveal that higher molecular weight binders not only enhance the discharge capacity and cycle life of these cathodes but also ensure robust adhesion and structural integrity.By optimizing binder molecular weights,we effectively shield the active materials from degradation and mechanical stress,significantly boosting the functionality and longevity of SSBs.These results underscore the paramount importance of binder properties in advancing the practical application of high-performance all-solid-state batteries.展开更多
Bauxite tailing(BT)slurry has been generated and accumulated in large quantities,posing a threat to the green and sustainable development of the alumina industry.The regression equation between the actual water conten...Bauxite tailing(BT)slurry has been generated and accumulated in large quantities,posing a threat to the green and sustainable development of the alumina industry.The regression equation between the actual water content and mud water separation rate was established to achieve efficient resource utilization,and the feasibility of foam lightweight soil(FLS)prepared from BT was investigated.The effects of industrial waste residues(fly ash and slag powder)on the properties of FLS were studied.Meanwhile,the micro-mechanisms were revealed by XRD,SEM-EDS,and TG-DSC.The results revealed that fly ash reduced the workability and compressive strength of FLS.Slag powder can significantly enhance the compressive strength of FLS,which increased by 18.60%-23.26%,17.07%-58.54% and 12.12%-52.12%,respectively.Besides,slag powder can improve the long-term water stability performance and enhance carbonation resistance.XRD and thermal analyses showed that adding fly ash decreased the hydration degree of FLS,leading to a decrease in the hydration products.Slag powder improved the pore structure and compacted the skeleton structure of FLS.This study would provide an effective way to realize the resource utilization of BT,fly ash,and slag powder,with certain socio-economic and environmental benefits.展开更多
Dairy cattle slurry is a source of nitrogen(N)that can substitute for synthetic fertilizers.This study aimed to identify combinations of synthetic fertilizers and slurry optimal for maize growth and N dynamics in Nort...Dairy cattle slurry is a source of nitrogen(N)that can substitute for synthetic fertilizers.This study aimed to identify combinations of synthetic fertilizers and slurry optimal for maize growth and N dynamics in Northeast China.In a two-year field experiment testing synthetic-to-slurry N fertilization ratios,slurry application increased grain yield and yield components,net economic benefit,and N use efficiency relative to synthetic fertilization but led to higher nitrous oxide and ammonia emissions.A 1:1-1:3 synthetic N:slurry N ratio and slurry application at 60-90 t ha^(-1)balanced productivity with N losses.展开更多
The lanthanum-cerium-based slurry(LC-slurry)is extensively utilized in the chemical mechanical polishing(CMP)of TFT-LCD glass substrates,optical lenses,and other glass products.Sodium hexametaphosphate(SHMP),as a disp...The lanthanum-cerium-based slurry(LC-slurry)is extensively utilized in the chemical mechanical polishing(CMP)of TFT-LCD glass substrates,optical lenses,and other glass products.Sodium hexametaphosphate(SHMP),as a dispersant,is commonly employed to enhance the dispersion properties of LCslurry for improved polishing performance.However,the tendency of sedimentation to form a compacted sediment layer,which is challenging to redisperse,increases storage difficulty and polishing equipment failure risk,thereby limiting its utilization in CMP.In the present study,sodium carboxymethylcellulose(CMC-Na),a long-chain organic polymer,was employed to enhance the redispersibility of LC-slurry containing SHMP.A comprehensive investigation was conducted on the influence of CMC-Na dosage and slurry pH on dispersibility,redispersibility and polishing performance.Additionally,an analysis was carried out to elucidate the underlying mechanism behind the effect of CMC-Na.The study demonstrates that the LC-slurry,containing 250 ppm SHMP and 500 ppm CMC-Na,exhibits excellent dispersibility and redispersibility.Further polishing tests demonstrate that compared to the LC-slurry containing only SHMP,utilizing the slurry containing both SHMP and CMC-Na at various pH for polishing thin film transistor liquid crystal display(TFT-LCD)glass substrates results in a reduction of both material removal rate(MRR)and surface roughness(Sa).Specifically,when adjusting the slurry to a pH range of 5-6,the MRR can reach up to 330 nm/min,which closely approximates the MRR achieved by LC-slurry containing only 250 ppm SHMP at corresponding pH values.Meanwhile,after polishing,the surface roughness of the glass substrate measures approximately 0.47 nm.展开更多
Reef limestone is buried in the continental shelf and marine environment.Understanding the mechanisms governing filter cake formation in coral reef limestone strata is essential for various engineering activities in c...Reef limestone is buried in the continental shelf and marine environment.Understanding the mechanisms governing filter cake formation in coral reef limestone strata is essential for various engineering activities in coastal areas,including slurry pressure balanced(SPB)shield tunneling,which are currently not well understood.This study systematically investigates the slurry infiltration characteristics of different coral reef limestone types with inherent anisotropy,identified by growth line orientations,through a series of micro-infiltration column tests.Multiple slurry concentrations and pressures were used to analyze their effects on slurry infiltration dynamics and filter cake formation.Pre-and post-infiltration CT scanning was conducted to examine skeletal morphology and reconstruct the pore network structure of coral reef limestone samples.The results show that while increased slurry concentrations and pressures generally improve filter cake formation,excessive pressure can compromise filter cake integrity.By employing Dijkstra’s algorithm in a pore network model,the study identified primary seepage pathways,highlighting the significant role of near-vertical throat clusters in the infiltration process.A comprehensive analysis of pore structure and connectivity indices before and after infiltration revealed that the orientation of growth lines in coral reef limestone is the primary factor influencing macroscopic slurry infiltration behavior.These findings offer valuable insights for the design and execution of tunneling projects through coral reef limestone formations,especially in coastal regions.展开更多
This study investigates the leaching and purification processes for dunite slurry,a common mining waste material,and the carbonation processes for the mineralization of CO_(2) with Mg^(2+).Results indicate that HCl is...This study investigates the leaching and purification processes for dunite slurry,a common mining waste material,and the carbonation processes for the mineralization of CO_(2) with Mg^(2+).Results indicate that HCl is a promising leaching agent,and pH and temperature are major factors in controlling the efficiency of the leaching process,with leaching efficiencies of 82%achieved after 4 h using 2 M HCl solution at 75℃.The removal of other ions like Fe^(3+),Fe^(2+),and Al^(3+)through the purification of the leachate using ammonium hydroxide was also proven to be effective,completely removing iron and aluminum from the leachate from starting concentrations of 3.10 and 0.40 g/L,respectively.The carbonation of magnesium at room temperature was investigated with both purified leachate and pure MgCl_(2) aqueous solution.Nesquehonite crystals began to form after 1.5 h with a conversion of Mg^(2+)to nesquehonite of approximately 5%.The produced crystals possess a needle-like shape,which could be modified using the biopolymers pectin and xanthan.Pectin had a limited influence on the length of the crystals,reducing the needle length with increasing pectin concentration.Xanthan,on the other hand,shortened and widened the needle-like structure into a column shape as more xanthan was added.This study demonstrates the potential for this process to utilize mining wastes and sequester CO_(2),producing useful mineral products in the process.展开更多
Integrating high-nickel layered oxide cathodes with aqueous slurry electrode preparation routes holds the potential to simultaneously meet the demands for high energy density and low-cost production of lithium-ion bat...Integrating high-nickel layered oxide cathodes with aqueous slurry electrode preparation routes holds the potential to simultaneously meet the demands for high energy density and low-cost production of lithium-ion batteries.However,the influence of dual exposure to air and liquid water as well as the heating treatment during aqueous slurry electrode processing on the high-nickel layered oxide electrode is yet to be understood.In this study,we systematically investigate the structural evolution and electro-chemical behaviors when LiNi_(0.83)Mn_(0.05)Co_(0.12)O_(2)(NMC83)is subjected to aqueous slurry processing.It was observed that the crystal structure near the surface of NMC83 is partially reconstructed to contain a mixture of rock-salt and layered phases when exposed to water,leading to the deteriorated rate capability of the NMC83 electrodes.This partial surface reconstruction layer completely converts into a pure rock-salt phase upon cycling,accompanied by the release of O_(2),Ni leaching,catalyzed decomposition of the electrolyte,and the formation of a thick cathode electrolyte interphase layer.The byproducts of the electrolyte and dissolved Ni could shuttle to the Li metal side,causing a crosstalk effect that results in a thick and unstable solid electrolyte interphase layer on the Li surface.These in combination severely undermined the cycling stability of the NMC83 electrodes obtained from the aqueous slurry.A mitigation strategy using molecular self-assembly technique was demonstrated to enhance the surface stability of water-treated NMC83.Our findings offer new insights for tailoring ambient environment stability and aqueous slurry processability for ultra-high nickel layered oxide and other water-sensitive cathode materials.展开更多
基金Project(2008BAB32B03) supported by the National Science and Technology Pillar Program during the 11th Five-year Plan Period of China
文摘Based on the pipe transportation of paste-like backfilling system of a certain deep coal mine,its dynamics process was simulated and analyzed.A two-dimensional dynamic model of extraordinary deep and lone pipe was built by GAMBIT,on the basis of which the simulation was done by implicit solver of FLUENT 2ddp.The results show that hydraulic loss of pipe transportation is less than the pressure produced by gravity,which means the backfilling material can flow by itself.When the inlet velocity is 3.2 m/s,the maximum velocity of 4.10 m/s is at the elbow and the maximum velocity in the horizontal pipe is 3.91 m/s,which can both meet the stability requirement.The results of the simulation are proved to be reliable by the residual monitor plotting of related parameter,so it can be concluded that the system of pipe transportation is safe.
基金Project(2012BAC09B02)supported by the National Science and Technology Pillar Program during the 12th Five-Year Plan Period,China
文摘To make backfilling body meet strength requirement,physical-chemical evaluation and proportioning tests were conducted on several backfilling materials.Jigging sands,#32.5 cement and fly ash were determined as backfilling aggregate,binding material and modified material,respectively.An optimized proportion of backfilling materials with a solid mass fraction of 78%and cement:fly ash:jigging sands mass ratio of 1:2:14,was suggested to Jiangan Pyrite Mine,China.The slurry made by optimized proportion produced obvious shear thinning phenomena,and was confirmed as paste-like slurry.To analyze its rheological characteristics,L-type pipeline test and Haake VT550 rotational viscometer test were conducted.Bingham and Casson fluid models were applied to several paste-like slurry samples to simulate flow and stress states;Casson fluid model was proved to have better simulation effect on paste-like slurry with shear thinning phenomena;rheological parameters of backfilling slurry made by suggested proportion were measured.Initial yield stress,average apparent viscosity and limiting viscosity are 55.35 Pa,1.216 Pa-s and 0.48 Pa-s,respectively.Compared with Bingham fluid model,Casson fluid model has a better simulation effect on paste-like slurry with shear thinning phenomena,through calculating the residual standard deviations.
基金Projects 2006BAB02A03 supported by the National Key Technology Research and Development ProgramProjects 2006BA02B05 by the 11th Five Year Key Program for Science and Technology Development of China
文摘A paste-like self-flowing pipeline transportation backfilling technology with coal gangue as aggregate is proposed to remove the potential damage caused by coal gangue piles. As well, the difficult problems of recovering high quality safety coal pillars and deep mining of the Suncun Coal Mine （SCM）, Xinwen Coal Group, Shandong are resolved. The physical-chemical properties of coal gangue, optimized proportion of materials, backfilling system and craft in the SCM were studied in the laboratory and then an industrial test was carried out on high quality coal pillars under a town. The results show that finely crushed kaolinized and fresh gangue with granularity less than 5 mm can be used as aggregate with fly ash to replace part of the cement and a composite water reducer as an additive, accounting for 1.0%-1.5% of the total amount of cement and fly ash. The recommended proportion is l（cement）：4（fly ash）： 15（coal gangue）, with a mass fraction of 72%-75%, rheoiogical paste-like properties and a strength of more than 0.7 MPa at 7 d. The sequence of adding cement, fly ash, water reducer and then coal gangue ensures that the suspended state of the slurry, reducing the wear and jam of pipelines. The working face is advancing continuously by the alternating craft of building block walls with coal gangue and backfilling mined-out gobs with paste-like slurry. The recovery rate is as high as 90% with a backfilling cost of 36.9 YuarffL good utilization of coal gangue and no subsidence on the surface. This technology provides a good theoretical basis and application experience for coal mines, cement backfilling with paste-like slurry.
文摘The experiments, which include the complete stress-strain curves, triaxial compressive loading history and the main factors affecting the compressive strength of the material, were made to research the mechanical properties of paste-like fill material. The results show that the material still has a relatively high load-bearing capacity after yielding. From the view of the backfill strength, the suitable content of the fine particles in the aggregates is 20%, the curing temperature of backfill slurry is about 20 centigrade degrees or higher. The backfill strength can reach 2.5-3.6 MPa when the binder dosage is 5%-8%. It can meet the needs for mining with backfill.
基金Hubei Provincial Key Research Program Project(2023BCB099).
文摘Utilizing phosphorus tailings as the raw material for foam concrete is a key approach to achieving sustainable and efficient resource utilization.During the preparation of phosphorus tailings-based foam concrete,slurry performance is critical to the successful production.Phosphorus tailings,cement and microsilica were used to prepare foam concrete slurry in this study.A rheometer was employed as a test tool to measure the variation of linear viscoelastic zone(LVR),viscosity,and yield stress of the slurries with different cement contents.The results indicate that the phosphorus tailings-cement-microsilica slurry exhibits shear-thinning properties,which aligns well with the Herschel-Bulkley model,showing a high degree of correlation.As the cement content increases,the energy storage modulus of the slurry rises,and the LVR length shows a nonlinear trend.The LVR reaches its maximum length of 0.04%when the cement content is 6 mass%or 8 mass%.The increment of the cement content leads to a more intricate internal network structure,which hinders the reconstruction rate of the flocculated structure after high-shear deformation.
基金support from the Scientific Research Foundation for the Introduction of Talent,Anhui University of Science and Technology(2023yjrc90)the Fundamental Research Funds of the AUST(2024JBQN0015)the Open Research Fund Program of Anhui Provincial Institute of Modern Coal Processing Technology,Anhui University of Science and Technology(MTY202302).
文摘The multipath application of green resources needs to be realised under the carbon neutrality goal.Worldwide,biomass is a resource in urgent need of treatment.In this paper,corn stover biomass(YM)or biochar with different particle sizes(YMF or YMX)was added during the preparation of coal-water slurry to investigate its effect on the performance of coal-water slurry and the micro-mechanism.The results showed that the fixed viscosity concentration of coal-water slurry(CYWS)with YM was only 47.42%,and the flowability was 49.9 mm,which made the slurry performance poor.The fixed viscosity concentration of coal-water slurry(CFWS)blended with YMF and coal-water slurry(CXWS)blended with YMX increased by 10.41%and 14.24%,respectively,compared with CYWS.Meanwhile,CXWS had the lowest thixotropy and yield stress,with a yield stress of only 16.13 Pa,which was 77.31 Pa lower than that of CYWS.This indicates that YMX treated by charring and milling is more favorable to be blended with coal to prepare coal-water slurry.This is due to the enhanced hydrophilicity and electronegativity of YMX.The enhanced hydrophilicity reduces the tendency to form three-dimensional networks in coal-water slurry,while the enhanced electronegativity improves the electrostatic repulsion between particles,which is beneficial to the dispersion of particles.In the subsequent EDLVO analyses,the same idea was proved.
基金supported by the Fundamental Research Funds for the Central Universities(Grant No.2023YJS053)the National Natural Science Foundation of China(Grant No.52278386).
文摘To fundamentally alleviate the excavation chamber clogging during slurry tunnel boring machine(TBM)advancing in hard rock,large-diameter short screw conveyor was adopted to slurry TBM of Qingdao Jiaozhou Bay Second Undersea Tunnel.To evaluate the discharging performance of short screw conveyor in different cases,the full-scale transient slurry-rock two-phase model for a short screw conveyor actively discharging rocks was established using computational fluid dynamics-discrete element method(CFD-DEM)coupling approach.In the fluid domain of coupling model,the sliding mesh technology was utilized to describe the rotations of the atmospheric composite cutterhead and the short screw conveyor.In the particle domain of coupling model,the dynamic particle factories were established to produce rock particles with the rotation of the cutterhead.And the accuracy and reliability of the CFD-DEM simulation results were validated via the field test and model test.Furthermore,a comprehensive parameter analysis was conducted to examine the effects of TBM operating parameters,the geometric design of screw conveyor and the size of rocks on the discharging performance of short screw conveyor.Accordingly,a reasonable rotational speed of screw conveyor was suggested and applied to Jiaozhou Bay Second Undersea Tunnel project.The findings in this paper could provide valuable references for addressing the excavation chamber clogging during ultra-large-diameter slurry TBM tunneling in hard rock for similar future.
文摘In this work,the influences of surface layer slurry at different temperatures(10℃,14℃,18℃,22℃)on wax patterns deformation,shrinkage,slurry coating characteristics,and the surface quality of the casting were investigated by using a single factor variable method.The surface morphologies of the shell molds produced by different temperatures of the surface(first)layer slurries were observed via electron microscopy.Furthermore,the microscopic composition of these shell molds was obtained by EDS,and the osmotic effect of the slurry on the wax patterns at different temperatures was also assessed by the PZ-200 Contact Angle detector.The forming reasons for the surface cracks and holes of thick and large ZTC4 titanium alloy by investment casting were analyzed.The experimental results show that the surface of the shell molds prepared by the surface layer slurry with a low temperature exhibits noticeable damage,which is mainly due to the poor coating performance and the serious expansion and contraction of wax pattern at low temperatures.The second layer shell material(SiO_(2),Al_(2)O_(3))immerses into the crack area of the surface layer,contacts and reacts with the molten titanium to form surface cracks and holes in the castings.With the increase of the temperature of surface layer slurry,the damage to the shell surface tends to weaken,and the composition of the shell molds'surface becomes more uniform with less impurities.The results show that the surface layer slurry at 22℃is evenly coated on the surface of the wax patterns with appropriate thickness,and there is no surface shell mold rupture caused by sliding slurry after sand leaching.The surface layer slurry temperature is consistent with the wax pattern temperature and the workshop temperature,so there is no damage of the surface layer shell caused by expansion and contraction.Therefore,the shell mold prepared by the surface layer slurry at this temperature has good integrity,isolating the contact between the low inert shell material and the titanium liquid effectively,and the ZTC4 titanium alloy cylinder casting prepared by this shell mold is smooth,without cracks and holes.
基金Projects(52104355,52074363,52374364)supported by the National Natural Science Foundation of ChinaProject(2023YFC2907904)supported by the National Key R&D Program of China。
文摘Traditional pyrometallurgical and hydrometallurgical methods to extract bismuth from sulfide ores face problems such as high cost,low-concentration SO_(2)generation,and long process time.In this study,the cyclone technology and slurry electrolysis method were combined.The bismuth sulfide ore was dissolved directly at the anode,while the high purity bismuth was deposited efficiently at the cathode under the advantages of the two methods.The short process and high-efficiency extraction of bismuth sulfide ore were realized,and the pollution of low-concentration SO_(2)was avoided.Then,the effects of several crucial experimental conditions(current density,reaction time,temperature,pH,liquid-solid ratio,and circulation flow rate)on the leaching efficiency and recovery efficiency of bismuth were investigated.The leaching and electrowinning mechanisms during the recovery process were also analyzed according to the research results of this paper to better understand the cyclone slurry electrolysis process.The experimental results showed that 95.19%bismuth was leached into the acid solution in the anode area under optimal conditions,and the recovery efficiency and purity of bismuth on the cathode reached 91.13%and 99.26%,respectively,which were better than those by the traditional hydrometallurgy recovery process.
基金supported by the National Key R&D Program of China(2021YFA1501200)the National Natural Science Foundation of China(NSFC U23B20169 and 22021004)the Project of R&D Department of CNPC(2020B-2011)。
文摘The influences of reaction temperature,duration,pressure,and catalyst concentration on the molecular transformation of residual slurry phase hydrocracking process were investigated.The molecular composition of the heteroatom compounds in the residue feedstock and its upgrading products were characterized using high-resolution Orbitrap mass spectrometry coupled with multiple ionization methods.The simultaneous promotion of cracking and hydrogenation reactions was observed with increasing of the reaction temperature and time.Specifically,there was a significant increase in the cracking degree of alkyl side chain,while the removal of low-condensation sulfur compounds such as sulfides and benzothiophenes was enhanced.In particular,the cracking reactions were more significantly facilitated by high temperatures,while an appropriately extended reaction time can result in the complete elimination of the aforementioned sulfur compounds with a lower degree of condensation.Under conditions of low hydrogen pressure and catalyst concentration,the products still exhibit a high relative abundance of easily convertible compounds such as sulfoxides,indicating a significant deficiency in the effectiveness of hydrogenation.The hydrogen pressure exhibits an optimal value,beyond which further increments have no effect on the composition and performance of the liquid product but can increase the yield of the liquid product.At significantly high catalyst concentration,the effect of desulfurization and deoxidation slightly diminishes,while the aromatic saturation of highly condensed compounds was notably enhanced.This hydrogenation saturation effect cannot be attained through manipulation of other operational parameters,thereby potentially benefiting subsequent product processing and utilization.This present study demonstrates a profound comprehension of the molecular-level residue slurry phase hydrocracking process,offering not only specific guide for process design and optimization but also valuable fundamental data for constructing reaction models at the molecular level.
基金financially supported by the National Natural Science Foundation of China (No. 52062029)the Key Science and Technology Project of Gansu Province (No. 18YF1GA064)the Natural Science Foundation of Gansu Provence (No. 25JRRA094)。
文摘Investment casting shell moulds are widely applied to cast alloys, but how to efficiently form a hierarchical porous structure inside the wall is an innovation and challenge. In this research, porous shell moulds with three infill patterns(rectilinear, grid, and honeycomb) were prepared using bauxite slurry and slurry extrusionbased additive manufacturing technology, and the effects of infill patterns on the properties were evaluated. The hierarchical pores inside the wall are composed of the macropores formed by infills and the micropores among bauxite particles. Different infill patterns result in changes in distribution and shape of pores, thereby affecting the properties of the shell moulds. The honeycomb pattern has more comprehensive advantages compared to the other two infill patterns. The samples prepared with the honeycomb pattern exhibit the highest bending strength(11.62 MPa) and porosity(41.6%), as well as good heat-transfer ability, with an average shrinkage rate within 2.0%. This work provides an attractive feasibility for fabricating shell moulds with hierarchical porous walls.
基金The authors gratefully acknowledge the filnancial support of the National Natural Science Foundation of China(Grant No.52369018)the Major Training Program of University Research and Innovation Platform of Gansu Provincial Department of Education(No.2024CXPT-09)+1 种基金the Administration of Central Funds Guiding the Local Science and Technology Development,China(Grant No.23ZYQA0320)the Double First-Class Key Program of Gansu Provincial Department of Education,Grant No.GCJ2022-38.
文摘Erosion in slurry pumps presents a persistent challenge in industrial applications.This study examines the erosion of the static components of a 150ZJ-C42 centrifugal slurry pump,currently in operation at a beneficiation plant,under varying particle conditions.Utilizing high-precision three-dimensional reverse engineering,the pump’s flow passage geometry was reconstructed to facilitate detailed erosion analysis.Focusing on the front and rear baffles of the pump chamber,as well as the volute,erosion patterns were analyzed for different particle volume concentrations and sizes.The results reveal that the highest erosion damage consistently occurs near the volute tongue,with wear being most severe in regions adjacent to the partition plate near the rear cover.Erosion damage intensity in this area correlates positively with particle diameter.Notably,the average erosion rate in the volute surpasses that of the front and rear chamber liners,reaching a value as high as 6.03×10^(-7)kg·m^(-2)·s^(-1)at a particle concentration of 9%and diameter of 0.1 mm,adversely impacting pump stability.For the pump chamber baffles,increased erosion is observed at a particle diameter of 0.05 mm under constant volume concentration conditions,while higher particle concentrations exacerbate localized erosion.
基金Funded by the State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Independent Research Project(No.SKLGP2022Z001)。
文摘We examined the mechanical strength and microscopic property effects of bottom ash(BA)recycled concrete made by partially substituting natural aggregates made from three industrial wastes,fly ash(FA),silica fume(SF),furnace slag(FS),and cement after BA was treated with slurry to improve the properties of BA and increase its utilisation.The compressive,flexural,splitting tensile strengths,and drying shrinkage test of the recycled concrete from BA were tested at the macroscopic level,and the specimens were analyzed by scanning electron microscopy(SEM)at the microscopic level.The experimental results show that the slurry treatment of BA results in a corresponding improvement in the macroscopic and microscopic properties of the obtained slurry-bound BA aggregates.The synergistic effect of FA and SF can better fill the pores on the surface of BA,which in turn can better improve the properties of recycled concrete.This study provides a theoretical support for improving the properties of BA and promoting its utilisation as a resource.
基金partially sponsored by the Office of Energy Efficiency and Renewable Energy(EERE)in the Vehicle Technologies Office(VTO)through the Advanced Battery Materials Research(BMR)Program,managed by DrsThe Department of Energy will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan(http://energy.gov/downloads/doe-public-access-plan).
文摘We demonstrate for the first time the critical influence of binder molecular weight on the performance of slurry-cast lithium nickel manganese cobalt oxide(NMC)cathodes in sulfide-based all-solid-state batteries(SSBs).SSBs are increasingly recognized as a safer and potentially more efficient alternative to traditional Li-ion batteries,owing to the superior ionic conductivities and inherent safety features of sulfide solid electrolytes.However,the integration of high-voltage NMC cathodes with sheet-type sulfide solid electrolytes presents significant fabrication challenges.Our findings reveal that higher molecular weight binders not only enhance the discharge capacity and cycle life of these cathodes but also ensure robust adhesion and structural integrity.By optimizing binder molecular weights,we effectively shield the active materials from degradation and mechanical stress,significantly boosting the functionality and longevity of SSBs.These results underscore the paramount importance of binder properties in advancing the practical application of high-performance all-solid-state batteries.
基金Project(5206800)supported by the National Natural Science Foundation of ChinaProject(2024JJA160096)supported by the Natural Science Foundation of Guangxi Province,China。
文摘Bauxite tailing(BT)slurry has been generated and accumulated in large quantities,posing a threat to the green and sustainable development of the alumina industry.The regression equation between the actual water content and mud water separation rate was established to achieve efficient resource utilization,and the feasibility of foam lightweight soil(FLS)prepared from BT was investigated.The effects of industrial waste residues(fly ash and slag powder)on the properties of FLS were studied.Meanwhile,the micro-mechanisms were revealed by XRD,SEM-EDS,and TG-DSC.The results revealed that fly ash reduced the workability and compressive strength of FLS.Slag powder can significantly enhance the compressive strength of FLS,which increased by 18.60%-23.26%,17.07%-58.54% and 12.12%-52.12%,respectively.Besides,slag powder can improve the long-term water stability performance and enhance carbonation resistance.XRD and thermal analyses showed that adding fly ash decreased the hydration degree of FLS,leading to a decrease in the hydration products.Slag powder improved the pore structure and compacted the skeleton structure of FLS.This study would provide an effective way to realize the resource utilization of BT,fly ash,and slag powder,with certain socio-economic and environmental benefits.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA28100200)the National Key Research and Development Program of China(2022YFD150080202)+1 种基金the Key Laboratory of Low-carbon Green Agriculture in Northeastern China,Ministry of Agriculture and Rural Affairs of the People’s Republic of China(LCGANE12)the Northeast Agricultural University Scholar Project and Academic Backbones Program(20YJXG13)。
文摘Dairy cattle slurry is a source of nitrogen(N)that can substitute for synthetic fertilizers.This study aimed to identify combinations of synthetic fertilizers and slurry optimal for maize growth and N dynamics in Northeast China.In a two-year field experiment testing synthetic-to-slurry N fertilization ratios,slurry application increased grain yield and yield components,net economic benefit,and N use efficiency relative to synthetic fertilization but led to higher nitrous oxide and ammonia emissions.A 1:1-1:3 synthetic N:slurry N ratio and slurry application at 60-90 t ha^(-1)balanced productivity with N losses.
基金supported by the National Key Research and Development Program(2021YFB3501103)Guiding Local Funding Projects for Scientific and Technological Development by Central Government in Hebei(216Z1402G)Youth Fund of GRINM Group Co.,Ltd.
文摘The lanthanum-cerium-based slurry(LC-slurry)is extensively utilized in the chemical mechanical polishing(CMP)of TFT-LCD glass substrates,optical lenses,and other glass products.Sodium hexametaphosphate(SHMP),as a dispersant,is commonly employed to enhance the dispersion properties of LCslurry for improved polishing performance.However,the tendency of sedimentation to form a compacted sediment layer,which is challenging to redisperse,increases storage difficulty and polishing equipment failure risk,thereby limiting its utilization in CMP.In the present study,sodium carboxymethylcellulose(CMC-Na),a long-chain organic polymer,was employed to enhance the redispersibility of LC-slurry containing SHMP.A comprehensive investigation was conducted on the influence of CMC-Na dosage and slurry pH on dispersibility,redispersibility and polishing performance.Additionally,an analysis was carried out to elucidate the underlying mechanism behind the effect of CMC-Na.The study demonstrates that the LC-slurry,containing 250 ppm SHMP and 500 ppm CMC-Na,exhibits excellent dispersibility and redispersibility.Further polishing tests demonstrate that compared to the LC-slurry containing only SHMP,utilizing the slurry containing both SHMP and CMC-Na at various pH for polishing thin film transistor liquid crystal display(TFT-LCD)glass substrates results in a reduction of both material removal rate(MRR)and surface roughness(Sa).Specifically,when adjusting the slurry to a pH range of 5-6,the MRR can reach up to 330 nm/min,which closely approximates the MRR achieved by LC-slurry containing only 250 ppm SHMP at corresponding pH values.Meanwhile,after polishing,the surface roughness of the glass substrate measures approximately 0.47 nm.
文摘Reef limestone is buried in the continental shelf and marine environment.Understanding the mechanisms governing filter cake formation in coral reef limestone strata is essential for various engineering activities in coastal areas,including slurry pressure balanced(SPB)shield tunneling,which are currently not well understood.This study systematically investigates the slurry infiltration characteristics of different coral reef limestone types with inherent anisotropy,identified by growth line orientations,through a series of micro-infiltration column tests.Multiple slurry concentrations and pressures were used to analyze their effects on slurry infiltration dynamics and filter cake formation.Pre-and post-infiltration CT scanning was conducted to examine skeletal morphology and reconstruct the pore network structure of coral reef limestone samples.The results show that while increased slurry concentrations and pressures generally improve filter cake formation,excessive pressure can compromise filter cake integrity.By employing Dijkstra’s algorithm in a pore network model,the study identified primary seepage pathways,highlighting the significant role of near-vertical throat clusters in the infiltration process.A comprehensive analysis of pore structure and connectivity indices before and after infiltration revealed that the orientation of growth lines in coral reef limestone is the primary factor influencing macroscopic slurry infiltration behavior.These findings offer valuable insights for the design and execution of tunneling projects through coral reef limestone formations,especially in coastal regions.
基金supported by Fonds Wetenschappelijk Onderzoek-Vlaanderen(FWO).D.M.acknowledges support from FWO in the form of strategic basic research fellowships(File number:1S13924N).
文摘This study investigates the leaching and purification processes for dunite slurry,a common mining waste material,and the carbonation processes for the mineralization of CO_(2) with Mg^(2+).Results indicate that HCl is a promising leaching agent,and pH and temperature are major factors in controlling the efficiency of the leaching process,with leaching efficiencies of 82%achieved after 4 h using 2 M HCl solution at 75℃.The removal of other ions like Fe^(3+),Fe^(2+),and Al^(3+)through the purification of the leachate using ammonium hydroxide was also proven to be effective,completely removing iron and aluminum from the leachate from starting concentrations of 3.10 and 0.40 g/L,respectively.The carbonation of magnesium at room temperature was investigated with both purified leachate and pure MgCl_(2) aqueous solution.Nesquehonite crystals began to form after 1.5 h with a conversion of Mg^(2+)to nesquehonite of approximately 5%.The produced crystals possess a needle-like shape,which could be modified using the biopolymers pectin and xanthan.Pectin had a limited influence on the length of the crystals,reducing the needle length with increasing pectin concentration.Xanthan,on the other hand,shortened and widened the needle-like structure into a column shape as more xanthan was added.This study demonstrates the potential for this process to utilize mining wastes and sequester CO_(2),producing useful mineral products in the process.
基金financially supported by the National Key R&D Program of China(2021YFB3800300)the National Natural Science Foundation of China(22179143 and 22309202)+1 种基金the Jiangsu Funding Program for Excellent Postdoctoral Talentthe Gusu Leading Talents Program(ZXL2023190)。
文摘Integrating high-nickel layered oxide cathodes with aqueous slurry electrode preparation routes holds the potential to simultaneously meet the demands for high energy density and low-cost production of lithium-ion batteries.However,the influence of dual exposure to air and liquid water as well as the heating treatment during aqueous slurry electrode processing on the high-nickel layered oxide electrode is yet to be understood.In this study,we systematically investigate the structural evolution and electro-chemical behaviors when LiNi_(0.83)Mn_(0.05)Co_(0.12)O_(2)(NMC83)is subjected to aqueous slurry processing.It was observed that the crystal structure near the surface of NMC83 is partially reconstructed to contain a mixture of rock-salt and layered phases when exposed to water,leading to the deteriorated rate capability of the NMC83 electrodes.This partial surface reconstruction layer completely converts into a pure rock-salt phase upon cycling,accompanied by the release of O_(2),Ni leaching,catalyzed decomposition of the electrolyte,and the formation of a thick cathode electrolyte interphase layer.The byproducts of the electrolyte and dissolved Ni could shuttle to the Li metal side,causing a crosstalk effect that results in a thick and unstable solid electrolyte interphase layer on the Li surface.These in combination severely undermined the cycling stability of the NMC83 electrodes obtained from the aqueous slurry.A mitigation strategy using molecular self-assembly technique was demonstrated to enhance the surface stability of water-treated NMC83.Our findings offer new insights for tailoring ambient environment stability and aqueous slurry processability for ultra-high nickel layered oxide and other water-sensitive cathode materials.
