The effect of Ti content on the microstructure and mechanical properties of as-cast light-weight Ti_(x)(AlVCr)_(100−x)medium entropy alloys was studied by compressive tests,X-ray diffraction,scanning electron microsco...The effect of Ti content on the microstructure and mechanical properties of as-cast light-weight Ti_(x)(AlVCr)_(100−x)medium entropy alloys was studied by compressive tests,X-ray diffraction,scanning electron microscopy and transmission electron microscopy.The results suggest that yield strength increases and then decreases with the increment of Ti content.The Ti_(60)(AlVCr)_(40)alloy has the best combination of high strength of 1204 MPa and uniform plastic strain of 70%,possessing a high specific yield strength of 255 MPa·cm^(3)/g.The enhancement of strength is mainly attributed to the synergic effects of solid-solution and coherent nano-precipitation strengthening,while dislocation motion such as dislocation pinning,entanglement and dislocation cells significantly increases the strain-hardening capacity.展开更多
Drying operations are of grave importance to realize the reduction and utilization of sewage sludge resources,but the conventional thermal evaporation drying(TED)technology presents challenges due to the need for a la...Drying operations are of grave importance to realize the reduction and utilization of sewage sludge resources,but the conventional thermal evaporation drying(TED)technology presents challenges due to the need for a large amount of thermal energy to conquer the phase-change latent heat of moisture.Herein,we report a non-phase change technology based on particle high-speed self-rotation in a cyclone for fast,low-temperature drying of viscous sludge with high-moisture contents.Dispersed phase medium(DPM)is introduced into the cyclone self-rotation drying(CSRD)reactor to enhance the dispersion of the viscous sludge.The effects of carrier gas temperature,feeding rate,size,and proportion of DPM particles in the drying process are systematically examined.Under optimal operating conditions,the weighted content of moisture in the viscous sludge could be reduced from 80%to 15.01%in less than 5 s,achieving a high drying efficiency of 95.79%.Theoretical calculations also reveal that 89.26%of the moisture is removed through non-phase change pathway,contributing to a 522-fold increase in the drying rate of CSRD compared to TED technology.This investigation presents a sustainable effective approach for high moisture viscous sludge treatment with low energy consumption and carbon emissions.展开更多
Steel–flux reactions involving the high aluminum(0.75–3.85 wt.%Al)low manganese(2.2 wt.%Mn)steel and the 18 wt.%SiO_(2)–18 wt.%Al2O3 mold flux were investigated.The results indicated that the reaction rate increase...Steel–flux reactions involving the high aluminum(0.75–3.85 wt.%Al)low manganese(2.2 wt.%Mn)steel and the 18 wt.%SiO_(2)–18 wt.%Al2O3 mold flux were investigated.The results indicated that the reaction rate increased when the initial aluminum content increased from 0.76 to 3.85 wt.%.Utilizing the two-film theory,a steel–flux reaction kinetic model controlled by mass transfer was established,which considered the influence of the initial composition on the density of liquid steel and flux.The mass transfer of aluminum in the steel phase was the reaction rate-determining step.It was confirmed that the mass transfer coefficient of Al was 1.87×10^(−4).The predicted results of the kinetic model were consistent and reliable with the experimental results.Thermodynamic equilibrium calculation was performed using FactSage 8.2,which was compared with the steel and flux final composition after 30 min.The content of initial aluminum in the liquid steel played a critical role in the SiO_(2)equilibrium content of the mold flux.In addition,the steel–flux reaction between[Al]and(SiO_(2))occurred with the initial SiO_(2)content in the mold flux lower than 3 wt.%.展开更多
The present work reports characteristics of dislocation slip behavior in an equi-atomic HfNbTiZr refractory medium entropy alloy(RMEA)and its systematic comparison with pure niobium(Nb).Fully-recrystallized specimens ...The present work reports characteristics of dislocation slip behavior in an equi-atomic HfNbTiZr refractory medium entropy alloy(RMEA)and its systematic comparison with pure niobium(Nb).Fully-recrystallized specimens were fabricated by cold rolling and subsequent annealing,and uniaxial tensile deformation was applied at room temperature.Slip trace morphologies on the surfaces of the tensile-deformed ma-terials were quantitatively characterized,and the so-calledψand x relationships of the observed slip traces were evaluated by a newly developed method for polycrystalline specimens.Wavy slip traces were observed in most grains in the pure Nb.They consisted of low-indexed slip planes,such as{110},and{112},and high-indexed(or undetermined)slip planes.Some straight slip traces persisting on the low-indexed slip planes were also found in the pure Nb.In contrast,straight slip traces were dominant in the RMEA.The straight slip traces in the RMEA were not parallel to particular slip planes but mostly distributed along the maximum shear stress plane(MSSP),indicating that frequent cross slip in very short intervals occurred.Large deviations of slip planes from the MSSP in a few grains of the RMEA were attributed to the slip transfer from neighboring grains as a characteristic of polycrystalline materi-als.Frequent cross slip in short intervals,attributed to homogeneous slip resistance distribution for screw dislocations in the RMEA originating from the chemical heterogeneity on an atomic scale,was proposed as a novel mechanism responsible for the unique slip behavior and macroscopic deformation behavior.展开更多
Fe-Cr-Ni austenitic alloys are extensively utilized in the hot-end components of nuclear light water reactors,turbine disks,and gas compressors.However,their low strength at elevated temperatures limits their engineer...Fe-Cr-Ni austenitic alloys are extensively utilized in the hot-end components of nuclear light water reactors,turbine disks,and gas compressors.However,their low strength at elevated temperatures limits their engineering applications.In this study,a novel precipit-ation-strengthened alloy system is developed by incorporating Al and Si elements into a FeCrNi equiatomic alloy.The results indicate that the FeCrNiAl_(x)Si_(x)(at%,x=0.1,0.2)alloys possess heterogeneous precipitation structures that feature a micron-scaleσphase at the grain boundaries and a nanoscale ordered body-centered cube(B2)phase within the grains.An exceptional strength-ductility synergy across a wide temperature range is achieved in FeCrNiAl_(0.1)Si_(0.1)alloys due to grain refinement and precipitation strengthening.Notably,a yield strength of 693.83 MPa,an ultimate tensile strength of 817.55 MPa,and a uniform elongation of 18.27%are attained at 873 K.The dislo-cation shearing mechanism for B2 phases and the Orowan bypass mechanism forσphase,coupled with a high density of nano-twins and stacking faults in the matrix,contribute to the excellent mechanical properties at cryogenic and ambient temperatures.Moreover,the emergence of serratedσphase and micro-twins in the matrix plays a crucial role in the strengthening and toughening mechanisms at inter-mediate temperatures.This study offers a novel perspective and strategy for the development of precipitation-hardened Fe-Cr-Ni austen-itic alloys with exceptional strength-ductility synergy over a broad temperature range.展开更多
A new metastable dual-phase Fe59 Cr13 Ni18 Al10 medium entropy alloy(MEA)with hierarchically heteroge-neous microstructure from micro-to nano-scale was designed in this work.Partially recrystallized FCC phase and lots...A new metastable dual-phase Fe59 Cr13 Ni18 Al10 medium entropy alloy(MEA)with hierarchically heteroge-neous microstructure from micro-to nano-scale was designed in this work.Partially recrystallized FCC phase and lots of NiAl-rich B2 precipitates are obtained by annealing and aging treatment.The yield strength of the MEA at room temperature(298 K)and liquid nitrogen temperature(77 K)increased from∼910 MPa and∼1250 MPa in the annealed state,respectively,to∼1145 MPa and∼1520 MPa in the aged state,while the uniform elongation maintained more than 15%.The excellent mechanical properties of the MEA both at 298 and 77 K are attributed to the co-activation of multiple strengthening mech-anisms,including fine grain,dislocation,precipitation,transformation-induced plasticity,stacking faults,and nano-twins.展开更多
Different application scenarios put forward diverse requirements of mechanical properties for magnesium alloys.In this study,the extruded Mg-Sc-Nd-Zn alloy series with high plasticity and medium strength was developed...Different application scenarios put forward diverse requirements of mechanical properties for magnesium alloys.In this study,the extruded Mg-Sc-Nd-Zn alloy series with high plasticity and medium strength was developed.The uniformly distributed Mg_(3)Nd(β_(1))phase,high-density twins,and the activated non-basal dislocation slips contribute to the high plasticity of Mg-Sc-Nd alloy.With the addition of Zn element,the appearance of coarse ScZn phases,which prevents the activation of{1012}tensile twins,leads to an increase in strength but a simultaneous decrease in the plasticity of the extruded alloys.Adjusting the Zn content in the Mg-Sc-Nd-xZn allows a series of alloys with various strengths and plasticity matching.The results obtained in this work are of great importance for developing a regulatable magnesium alloy series that aims at different application scenarios.展开更多
Reversible solid oxide cell(RSOC)is a new energy conversion device with significant applications,especially for power grid peaking shaving.However,the reversible conversion process of power generation/energy storage p...Reversible solid oxide cell(RSOC)is a new energy conversion device with significant applications,especially for power grid peaking shaving.However,the reversible conversion process of power generation/energy storage poses challenges for the performance and stability of air electrodes.In this work,a novel high-entropy perovskite oxide La_(0.2)Pr_(0.2)Gd_(0.2)Sm_(0.2)Sr_(0.2)Co_(0.8)Fe_(0.2)O_(3−δ)(HE-LSCF)is proposed and investigated as an air electrode in RSOC.The electrochemical behavior of HE-LSCF was studied as an air electrode in both fuel cell and electrolysis modes.The polarization impedance(Rp)of the HE-LSCF electrode is only 0.25Ω·cm^(2) at 800℃ in an air atmosphere.Notably,at an electrolytic voltage of 2 V and a temperature of 800℃,the current density reaches up to 1.68 A/cm^(2).The HE-LSCF air electrode exhibited excellent reversibility and stability,and its electrochemical performance remains stable after 100 h of reversible operation.With these advantages,HE-LSCF is shown to be an excellent air electrode for RSOC.展开更多
Metal Additive Manufacturing(MAM) technology has become an important means of rapid prototyping precision manufacturing of special high dynamic heterogeneous complex parts. In response to the micromechanical defects s...Metal Additive Manufacturing(MAM) technology has become an important means of rapid prototyping precision manufacturing of special high dynamic heterogeneous complex parts. In response to the micromechanical defects such as porosity issues, significant deformation, surface cracks, and challenging control of surface morphology encountered during the selective laser melting(SLM) additive manufacturing(AM) process of specialized Micro Electromechanical System(MEMS) components, multiparameter optimization and micro powder melt pool/macro-scale mechanical properties control simulation of specialized components are conducted. The optimal parameters obtained through highprecision preparation and machining of components and static/high dynamic verification are: laser power of 110 W, laser speed of 600 mm/s, laser diameter of 75 μm, and scanning spacing of 50 μm. The density of the subordinate components under this reference can reach 99.15%, the surface hardness can reach 51.9 HRA, the yield strength can reach 550 MPa, the maximum machining error of the components is 4.73%, and the average surface roughness is 0.45 μm. Through dynamic hammering and high dynamic firing verification, SLM components meet the requirements for overload resistance. The results have proven that MEM technology can provide a new means for the processing of MEMS components applied in high dynamic environments. The parameters obtained in the conclusion can provide a design basis for the additive preparation of MEMS components.展开更多
In recent years,medium entropy alloys have become a research hotspot due to their excellent physical and chemical performances.By controlling reasonable elemental composition and processing parameters,the medium entro...In recent years,medium entropy alloys have become a research hotspot due to their excellent physical and chemical performances.By controlling reasonable elemental composition and processing parameters,the medium entropy alloys can exhibit similar properties to high entropy alloys and have lower costs.In this paper,a FeCoNi medium entropy alloy precursor was prepared via sol-gel and coprecipitation methods,respectively,and FeCoNi medium entropy alloys were prepared by carbothermal and hydrogen reduction.The phases and magnetic properties of FeCoNi medium entropy alloy were investigated.Results showed that FeCoNi medium entropy alloy was produced by carbothermal and hydrogen reduction at 1500℃.Some carbon was detected in the FeCoNi medium entropy alloy prepared by carbothermal reduction.The alloy prepared by hydrogen reduction was uniform and showed a relatively high purity.Moreover,the hydrogen reduction product exhibited better saturation magnetization and lower coercivity.展开更多
Lightweight high/medium-entropy alloys(H/MEAs)possess attractive properties such as high strength-to-weight ratios,however,their limited room-temperature tensile ductility hinders their widespread engi-neering impleme...Lightweight high/medium-entropy alloys(H/MEAs)possess attractive properties such as high strength-to-weight ratios,however,their limited room-temperature tensile ductility hinders their widespread engi-neering implementation,for instance in aerospace structural components.This work achieved a transfor-mative improvement of room-temperature tensile ductility in Ti-V-Zr-Nb MEAs with densities of 5.4-6.5 g/cm3,via ingenious composition modulation.Through the systematic co-adjustment of Ti and V contents,an intrinsic ductility mechanism was unveiled,manifested by a transition from predominant intergranular brittle fracture to pervasive ductile dimpled rupture.Notably,the modulated deformation mechanisms evolved from solitary slip toward collaborative multiple slip modes,without significantly compromising strength.Compared to equimolar Ti-V-Zr-Nb,a(Ti1.5V)3ZrNb composition demonstrated an impressive 360%improvement in elongation while sustaining a high yield strength of around 800 MPa.Increasing Ti and V not only purified the grain boundaries by reducing detrimental phases,but also tai-lored the deformation dislocation configurations.These insights expanded the applicability of lightweight HEAs to areas demanding combined high strength and ductility.展开更多
The influence of Nb-V microalloying on the hot deformation behavior and microstructures of medium Mn steel(MMS)was investigated by uniaxial hot compression tests.By establishing the constitutive equations for simulati...The influence of Nb-V microalloying on the hot deformation behavior and microstructures of medium Mn steel(MMS)was investigated by uniaxial hot compression tests.By establishing the constitutive equations for simulating the measured flow curves,we successfully constructed deformation activation energy(Q)maps and processing maps for identifying the region of flow instability.We concluded the following consequences of Nb-V alloying for MMS.(i)The critical strain increases and the increment diminishes with the increasing deformation temperature,suggesting that NbC precipitates more efficiently retard dynamic recrystallization(DRX)in MMS compared with solute Nb.(ii)The deformation activation energy of MMS is significantly increased and even higher than that of some reported high Mn steels,suggesting that its ability to retard DRX is greater than that of the high Mn content.(iii)The hot workability of MMS is improved by narrowing the hot processing window for the unstable flow stress,in which fine recrystallized and coarse unrecrystallized grains are present.展开更多
Due to the limitations of spatial bandwidth product and data transmission bandwidth,the field of view,resolution,and imaging speed constrain each other in an optical imaging system.Here,a fast-zoom and high-resolution...Due to the limitations of spatial bandwidth product and data transmission bandwidth,the field of view,resolution,and imaging speed constrain each other in an optical imaging system.Here,a fast-zoom and high-resolution sparse compound-eye camera(CEC)based on dual-end collaborative optimization is proposed,which provides a cost-effective way to break through the trade-off among the field of view,resolution,and imaging speed.In the optical end,a sparse CEC based on liquid lenses is designed,which can realize large-field-of-view imaging in real time,and fast zooming within 5 ms.In the computational end,a disturbed degradation model driven super-resolution network(DDMDSR-Net)is proposed to deal with complex image degradation issues in actual imaging situations,achieving high-robustness and high-fidelity resolution enhancement.Based on the proposed dual-end collaborative optimization framework,the angular resolution of the CEC can be enhanced from 71.6"to 26.0",which provides a solution to realize high-resolution imaging for array camera dispensing with high optical hardware complexity and data transmission bandwidth.Experiments verify the advantages of the CEC based on dual-end collaborative optimization in high-fidelity reconstruction of real scene images,kilometer-level long-distance detection,and dynamic imaging and precise recognition of targets of interest.展开更多
GH4169 joints manufactured by Linear Friction Welding(LFW)are subjected to tensile test and stair-case method to evaluate the High Cycle Fatigue(HCF)performance at 650℃.The yield and ultimate tensile strengths are 58...GH4169 joints manufactured by Linear Friction Welding(LFW)are subjected to tensile test and stair-case method to evaluate the High Cycle Fatigue(HCF)performance at 650℃.The yield and ultimate tensile strengths are 582 MPa and 820 MPa,respectively.The HCF strength of joint reaches 400 MPa,which is slightly lower than that of Base Metal(BM),indicating reliable quality of this type of joint.The microstructure observation results show that all cracks initiate at the inside of specimens and transfer into deeper region with decrease of external stress,and the crack initiation site is related with microhardness of matrix.The Electron Backscattered Diffraction(EBSD)results of the observed regions with different distances to fracture show that plastic deformation plays a key role in HCF,and the Schmid factor of most grains near fracture exceeds 0.4.In addition,the generation of twins plays a vital role in strain concentration release and coordinating plastic deformation among grains.展开更多
Both fractional crystallization and fluid-melt-crystal interaction are involved in the formation of highly fractionated granites.This paper assessed those two processes using geochemistry of muscovite and tourmaline a...Both fractional crystallization and fluid-melt-crystal interaction are involved in the formation of highly fractionated granites.This paper assessed those two processes using geochemistry of muscovite and tourmaline and bulkrock chemistry of multi-phase Wangxianling granitoids,South China.Compositional variations suggest the coarse-grained muscovite granite is produced from fractional crystallization of the two-mica granite whereas the fine-grained muscovite granite represents a distinct magma pulse.Progressive fractionation of quartz,feldspar and biotite leads to elevated boron and aluminum content in melt which promoted muscovite and tourmaline to crystallize,which promotes two-mica granite evolving towards tourmaline-bearing muscovite granite.Fluid-melt-crystal interaction occurred at the magmatichydrothermal transitional stage and resulted in the textural and chemical zonings of tourmaline and muscovite in finegrained muscovite granite.The rims of both tourmaline and muscovite are characterized by the enrichment of fluid mobile elements such as Li,Mn,Cs and Zn and heavierδ^(11)B values of the tourmaline rims(-15.0‰to-13.6‰)compared to cores(-15.7‰to-14.3‰).Meanwhile,significant M-type REE tetrad effects(TE_(1,3)=1.07-1.18)and low K/Rb ratios(48-52)also correspond to fluid-melt-crystal interaction.This study shows zoned muscovite and tourmaline can be excellent tracers of fractional crystallization and late-stage fluid-melt-crystal interaction in highly evolved magmatic systems.展开更多
Up-and-coming high-temperature materials,refractory high entropy alloys,are suffering from lower oxidation resistance,restricting their applications in the aerospace field.In this study,two novel treatments of Al-depo...Up-and-coming high-temperature materials,refractory high entropy alloys,are suffering from lower oxidation resistance,restricting their applications in the aerospace field.In this study,two novel treatments of Al-deposited and remelted were developed to refine the microstructure and enhance the oxidation resistance of refractory high entropy alloy using electron beam freeform fabrication(EBF3).Finer and short-range ordering structures were observed in the remelted sample,whereas the Al-deposited sample showcased the formation of silicide and intermetallic phases.High-temperature cyclic and isothermal oxidation tests at 1000℃ were carried out.The total weight gain after 60 h of cyclic oxidation decreased by 17.49%and 30.46%for the remelted and deposited samples,respectively,compared to the as-cast state.Oxidation kinetics reveal an evident lower mass gain and oxidation rate in the treated samples.A multilayer oxide consisting of TiO_(2)+Al_(2)O_(3)+SiO_(2)+AlNbO_(4) was studied for its excellent oxidation resistance.The oxidation behavior of rutile,corundum and other oxides was analyzed using first principles calculations and chemical defect analysis.Overall,this research,which introduces novel treatments,offers promising insights for enhancing the inherent oxidation resistance of refractory high entropy alloys.展开更多
Low-to medium-maturity oil shale resources display substantial reserves, offering promising prospects for in-situ conversion inChina. Investigating the evolution of the mechanical properties of the reservoir and capro...Low-to medium-maturity oil shale resources display substantial reserves, offering promising prospects for in-situ conversion inChina. Investigating the evolution of the mechanical properties of the reservoir and caprock under in-situ high-temperature and confine-ment conditions is of considerable importance. Compared to conventional mechanical experiments on rock samples after high-temperat-ure treatment, in-situ high-temperature experiments can more accurately characterize the behavior of rocks in practical engineering,thereby providing a more realistic reflection of their mechanical properties. In this study, an in-situ high-temperature triaxial compressiontesting machine is developed to conduct in-situ compression tests on sandstone at different temperatures(25, 200, 400, 500, and 650℃)and confining pressures(0, 10, and 20 MPa). Based on the experimental results, the temperature-dependent changes in compressivestrength, peak strain, elastic modulus, Poisson's ratio, cohesion, and internal friction angle are thoroughly analyzed and discussed. Resultsindicate that the mass of sandstone gradually decreases as the temperature increases. The thermal conductivity and thermal diffusivity ofsandstone exhibit a linear relationship with temperature. Peak stress decreases as the temperature rises, while it increases with higher con-fining pressures. Notably, the influence of confining pressure on peak stress diminishes at higher temperatures. Additionally, as the tem-perature rises, the Poisson's ratio of sandstone decreases. The internal friction angle also decreases with increasing temperature, with 400℃ acting as the threshold temperature. Interestingly, under uniaxial conditions, the damage stress of sandstone is less affected by tem-perature. However, when the confining pressure is 10 or 20 MPa, the damage stress decreases as the temperature increases. This study en-hances our understanding of the influence of in-situ high-temperature and confinement conditions on the mechanical properties of sand-stone strata. The study also provides valuable references and experimental data that support the development of low-to medium-maturityoil shale resources.展开更多
The soaring demand for smart portable electronics and electric vehicles is propelling the advancements in high-energy–density lithium-ion batteries.Lithium manganese iron phosphate(LiMn_(x)Fe_(1-x)PO_(4))has garnered...The soaring demand for smart portable electronics and electric vehicles is propelling the advancements in high-energy–density lithium-ion batteries.Lithium manganese iron phosphate(LiMn_(x)Fe_(1-x)PO_(4))has garnered significant attention as a promising positive electrode material for lithium-ion batteries due to its advantages of low cost,high safety,long cycle life,high voltage,good high-temperature performance,and high energy density.Although LiMn_(x)Fe_(1-x)PO_(4)has made significant breakthroughs in the past few decades,there are still facing great challenges in poor electronic conductivity and Li-ion diffusion,manganese dissolution affecting battery cycling performance,as well as low tap density.This review systematically summarizes the reaction mechanisms,various synthesis methods,and electrochemical properties of LiMn_(x)Fe_(1-x)PO_(4)to analyze reaction processes accurately and guide material preparation.Later,the main challenges currently faced are concluded,and the corresponding various modification strategies are discussed to enhance the reaction kinetics and electrochemical performance of LiMn_(x)Fe_(1-x)PO_(4),including multi-scale particle regulation,heteroatom doping,surface coating,as well as microscopic morphology design.Finally,in view of the current research challenges faced by intrinsic reaction processes,kinetics,and energy storage applications,the promising research directions are anticipated.More importantly,it is expected to provide key insights into the development of high-performance and stable LiMn_(x)Fe_(1-x)PO_(4)materials,to achieve practical energy storage requirements.展开更多
The Early Cambrian Yuertusi Formation(Є_(1)y)in the Tarim Basin of China deposits a continuously developed suite of organic-rich black mudstones,which constitute an important source of oil and gas reservoirs in the Pa...The Early Cambrian Yuertusi Formation(Є_(1)y)in the Tarim Basin of China deposits a continuously developed suite of organic-rich black mudstones,which constitute an important source of oil and gas reservoirs in the Paleozoic.However,its hydrocarbon generation and evolution characteristics and resource potential have long been constrained by deeply buried strata and previous research.In this paper,based on the newly obtained ultra-deep well drilling data,the hydrocarbon generation and expulsion model ofЄ_(1)y shale was established by using data-driven Monte Carlo simulation,upon which the hydrocarbon generation,expulsion,and retention amounts were calculated by using the diagenetic method.The research indicates that theЄ_(1)y shale reaches the hydrocarbon generation and expulsion threshold at equivalent vitrinite reflectances of 0.46%and 0.72%,respectively.The cumulative hydrocarbon generation is 68.88×10^(10)t,the cumulative hydrocarbon expulsion is 35.59×10^(10)t,and the cumulative residual hydrocarbon is 33.29×10^(10)t.This paper systematically and quantitatively calculates the hydrocarbon expulsion at various key geological periods for theЄ_(1)y source rocks in the study area for the first time,more precisely confirming that the black shale of theЄ_(1)y is the most significant source rock contributing to the marine oil and gas resources in the Tarim Basin,filling the gap in hydrocarbon expulsion calculation in the study area,and providing an important basis for the formation and distribution of Paleozoic hydrocarbon reservoirs.The prospect of deep ultra-deep oil and gas exploration in the Tarim Basin is promising.Especially,the large area of dolomite reservoirs under the Cambrian salt and source rock interiors are the key breakthrough targets for the next exploration in the Tarim Basin.展开更多
The deterioration of aqueous zinc-ion batteries(AZIBs)is confronted with challenges such as unregulated Zn^(2+)diffusion,dendrite growth and severe decay in battery performance under harsh environments.Here,a design c...The deterioration of aqueous zinc-ion batteries(AZIBs)is confronted with challenges such as unregulated Zn^(2+)diffusion,dendrite growth and severe decay in battery performance under harsh environments.Here,a design concept of eutectic electrolyte is presented by mixing long chain polymer molecules,polyethylene glycol dimethyl ether(PEGDME),with H_(2)O based on zinc trifluoromethyl sulfonate(Zn(OTf)2),to reconstruct the Zn^(2+)solvated structure and in situ modified the adsorption layer on Zn electrode surface.Molecular dynamics simulations(MD),density functional theory(DFT)calculations were combined with experiment to prove that the long-chain polymer-PEGDME could effectively reduce side reactions,change the solvation structure of the electrolyte and priority absorbed on Zn(002),achieving a stable dendrite-free Zn anode.Due to the comprehensive regulation of solvation structure and zinc deposition by PEGDME,it can stably cycle for over 3200 h at room temperature at 0.5 mA/cm^(2)and 0.5 mAh/cm^(2).Even at high-temperature environments of 60℃,it can steadily work for more than 800 cycles(1600 h).Improved cyclic stability and rate performance of aqueous Zn‖VO_(2)batteries in modified electrolyte were also achieved at both room and high temperatures.Beyond that,the demonstration of stable and high-capacity Zn‖VO_(2)pouch cells also implies its practical application.展开更多
基金supported by the National Natural Science Foundation of China(Nos.52071176,12072331,51771090,51671103)the Priority Academic Program Development(PAPD)of Jiangsu Higher Education Institutions,China.
文摘The effect of Ti content on the microstructure and mechanical properties of as-cast light-weight Ti_(x)(AlVCr)_(100−x)medium entropy alloys was studied by compressive tests,X-ray diffraction,scanning electron microscopy and transmission electron microscopy.The results suggest that yield strength increases and then decreases with the increment of Ti content.The Ti_(60)(AlVCr)_(40)alloy has the best combination of high strength of 1204 MPa and uniform plastic strain of 70%,possessing a high specific yield strength of 255 MPa·cm^(3)/g.The enhancement of strength is mainly attributed to the synergic effects of solid-solution and coherent nano-precipitation strengthening,while dislocation motion such as dislocation pinning,entanglement and dislocation cells significantly increases the strain-hardening capacity.
基金supported by the National Key Research and Development Program of China(2019YFA0705800)the National Natural Science Foundation of China(52030001)the Science&Technology Commission of Shanghai Municipality(20dz1207600).
文摘Drying operations are of grave importance to realize the reduction and utilization of sewage sludge resources,but the conventional thermal evaporation drying(TED)technology presents challenges due to the need for a large amount of thermal energy to conquer the phase-change latent heat of moisture.Herein,we report a non-phase change technology based on particle high-speed self-rotation in a cyclone for fast,low-temperature drying of viscous sludge with high-moisture contents.Dispersed phase medium(DPM)is introduced into the cyclone self-rotation drying(CSRD)reactor to enhance the dispersion of the viscous sludge.The effects of carrier gas temperature,feeding rate,size,and proportion of DPM particles in the drying process are systematically examined.Under optimal operating conditions,the weighted content of moisture in the viscous sludge could be reduced from 80%to 15.01%in less than 5 s,achieving a high drying efficiency of 95.79%.Theoretical calculations also reveal that 89.26%of the moisture is removed through non-phase change pathway,contributing to a 522-fold increase in the drying rate of CSRD compared to TED technology.This investigation presents a sustainable effective approach for high moisture viscous sludge treatment with low energy consumption and carbon emissions.
基金support from the National Key R&D Program of China(No.2023YFB3709900)the National Natural Science Foundation of China(Grant No.U22A20171).
文摘Steel–flux reactions involving the high aluminum(0.75–3.85 wt.%Al)low manganese(2.2 wt.%Mn)steel and the 18 wt.%SiO_(2)–18 wt.%Al2O3 mold flux were investigated.The results indicated that the reaction rate increased when the initial aluminum content increased from 0.76 to 3.85 wt.%.Utilizing the two-film theory,a steel–flux reaction kinetic model controlled by mass transfer was established,which considered the influence of the initial composition on the density of liquid steel and flux.The mass transfer of aluminum in the steel phase was the reaction rate-determining step.It was confirmed that the mass transfer coefficient of Al was 1.87×10^(−4).The predicted results of the kinetic model were consistent and reliable with the experimental results.Thermodynamic equilibrium calculation was performed using FactSage 8.2,which was compared with the steel and flux final composition after 30 min.The content of initial aluminum in the liquid steel played a critical role in the SiO_(2)equilibrium content of the mold flux.In addition,the steel–flux reaction between[Al]and(SiO_(2))occurred with the initial SiO_(2)content in the mold flux lower than 3 wt.%.
基金supported by the Elements Strategy Initiative for Structural Materials(ESISM,No.JPMXP0112101000)the JSP EIG CONCERT-Japan(No.JPMJSC21C6)+5 种基金the Grant-in-Aid for Scientific Research on Innovative Area“High Entropy Alloys”(Nos.JP18H05455 and JP18H05451)the Grant-in-Aid for Scientific Re-search(A)(Nos.JP20H00306 and JP23H00234)the Grant-in-Aid for Research Activity Start-up(No.JP21K20487)the Grant-in-Aid for Early-Career Scientists(No.JP22K14501)the Grant-in-Aid for JSPS Research Fellow(No.JP18J20766)supported by China Scholarship Council(CSC),China.
文摘The present work reports characteristics of dislocation slip behavior in an equi-atomic HfNbTiZr refractory medium entropy alloy(RMEA)and its systematic comparison with pure niobium(Nb).Fully-recrystallized specimens were fabricated by cold rolling and subsequent annealing,and uniaxial tensile deformation was applied at room temperature.Slip trace morphologies on the surfaces of the tensile-deformed ma-terials were quantitatively characterized,and the so-calledψand x relationships of the observed slip traces were evaluated by a newly developed method for polycrystalline specimens.Wavy slip traces were observed in most grains in the pure Nb.They consisted of low-indexed slip planes,such as{110},and{112},and high-indexed(or undetermined)slip planes.Some straight slip traces persisting on the low-indexed slip planes were also found in the pure Nb.In contrast,straight slip traces were dominant in the RMEA.The straight slip traces in the RMEA were not parallel to particular slip planes but mostly distributed along the maximum shear stress plane(MSSP),indicating that frequent cross slip in very short intervals occurred.Large deviations of slip planes from the MSSP in a few grains of the RMEA were attributed to the slip transfer from neighboring grains as a characteristic of polycrystalline materi-als.Frequent cross slip in short intervals,attributed to homogeneous slip resistance distribution for screw dislocations in the RMEA originating from the chemical heterogeneity on an atomic scale,was proposed as a novel mechanism responsible for the unique slip behavior and macroscopic deformation behavior.
基金supported by the National Natural Science Foundation of China(Nos.12072220,12102291,and 12225207)the Science and Technology Innovation Teams of Shanxi Province,China(No.202204051002006)the Central Guidance on Local Science and Technology Development Fund of Shanxi Province,China(No.YDZJSX2021B002).
文摘Fe-Cr-Ni austenitic alloys are extensively utilized in the hot-end components of nuclear light water reactors,turbine disks,and gas compressors.However,their low strength at elevated temperatures limits their engineering applications.In this study,a novel precipit-ation-strengthened alloy system is developed by incorporating Al and Si elements into a FeCrNi equiatomic alloy.The results indicate that the FeCrNiAl_(x)Si_(x)(at%,x=0.1,0.2)alloys possess heterogeneous precipitation structures that feature a micron-scaleσphase at the grain boundaries and a nanoscale ordered body-centered cube(B2)phase within the grains.An exceptional strength-ductility synergy across a wide temperature range is achieved in FeCrNiAl_(0.1)Si_(0.1)alloys due to grain refinement and precipitation strengthening.Notably,a yield strength of 693.83 MPa,an ultimate tensile strength of 817.55 MPa,and a uniform elongation of 18.27%are attained at 873 K.The dislo-cation shearing mechanism for B2 phases and the Orowan bypass mechanism forσphase,coupled with a high density of nano-twins and stacking faults in the matrix,contribute to the excellent mechanical properties at cryogenic and ambient temperatures.Moreover,the emergence of serratedσphase and micro-twins in the matrix plays a crucial role in the strengthening and toughening mechanisms at inter-mediate temperatures.This study offers a novel perspective and strategy for the development of precipitation-hardened Fe-Cr-Ni austen-itic alloys with exceptional strength-ductility synergy over a broad temperature range.
基金supported by the National Natural Science Foundation of China(Nos.52101053 and 52274399)the Henan Provincial Science and Technology Research Project(No.232102231025).
文摘A new metastable dual-phase Fe59 Cr13 Ni18 Al10 medium entropy alloy(MEA)with hierarchically heteroge-neous microstructure from micro-to nano-scale was designed in this work.Partially recrystallized FCC phase and lots of NiAl-rich B2 precipitates are obtained by annealing and aging treatment.The yield strength of the MEA at room temperature(298 K)and liquid nitrogen temperature(77 K)increased from∼910 MPa and∼1250 MPa in the annealed state,respectively,to∼1145 MPa and∼1520 MPa in the aged state,while the uniform elongation maintained more than 15%.The excellent mechanical properties of the MEA both at 298 and 77 K are attributed to the co-activation of multiple strengthening mech-anisms,including fine grain,dislocation,precipitation,transformation-induced plasticity,stacking faults,and nano-twins.
基金Project supported by the National Natural Science Foundation of China(52301107)the National Key Research and Development Program of China(2021YFC2400703)。
文摘Different application scenarios put forward diverse requirements of mechanical properties for magnesium alloys.In this study,the extruded Mg-Sc-Nd-Zn alloy series with high plasticity and medium strength was developed.The uniformly distributed Mg_(3)Nd(β_(1))phase,high-density twins,and the activated non-basal dislocation slips contribute to the high plasticity of Mg-Sc-Nd alloy.With the addition of Zn element,the appearance of coarse ScZn phases,which prevents the activation of{1012}tensile twins,leads to an increase in strength but a simultaneous decrease in the plasticity of the extruded alloys.Adjusting the Zn content in the Mg-Sc-Nd-xZn allows a series of alloys with various strengths and plasticity matching.The results obtained in this work are of great importance for developing a regulatable magnesium alloy series that aims at different application scenarios.
基金supported by Fundamental Research Funds for the Central Universities(2023KYJD1008)the Science Research Projects of the Anhui Higher Education Institutions of China(2022AH051582).
文摘Reversible solid oxide cell(RSOC)is a new energy conversion device with significant applications,especially for power grid peaking shaving.However,the reversible conversion process of power generation/energy storage poses challenges for the performance and stability of air electrodes.In this work,a novel high-entropy perovskite oxide La_(0.2)Pr_(0.2)Gd_(0.2)Sm_(0.2)Sr_(0.2)Co_(0.8)Fe_(0.2)O_(3−δ)(HE-LSCF)is proposed and investigated as an air electrode in RSOC.The electrochemical behavior of HE-LSCF was studied as an air electrode in both fuel cell and electrolysis modes.The polarization impedance(Rp)of the HE-LSCF electrode is only 0.25Ω·cm^(2) at 800℃ in an air atmosphere.Notably,at an electrolytic voltage of 2 V and a temperature of 800℃,the current density reaches up to 1.68 A/cm^(2).The HE-LSCF air electrode exhibited excellent reversibility and stability,and its electrochemical performance remains stable after 100 h of reversible operation.With these advantages,HE-LSCF is shown to be an excellent air electrode for RSOC.
基金funded by the National Natural Science Foundation of China Youth Fund(Grant No.62304022)Science and Technology on Electromechanical Dynamic Control Laboratory(China,Grant No.6142601012304)the 2022e2024 China Association for Science and Technology Innovation Integration Association Youth Talent Support Project(Grant No.2022QNRC001).
文摘Metal Additive Manufacturing(MAM) technology has become an important means of rapid prototyping precision manufacturing of special high dynamic heterogeneous complex parts. In response to the micromechanical defects such as porosity issues, significant deformation, surface cracks, and challenging control of surface morphology encountered during the selective laser melting(SLM) additive manufacturing(AM) process of specialized Micro Electromechanical System(MEMS) components, multiparameter optimization and micro powder melt pool/macro-scale mechanical properties control simulation of specialized components are conducted. The optimal parameters obtained through highprecision preparation and machining of components and static/high dynamic verification are: laser power of 110 W, laser speed of 600 mm/s, laser diameter of 75 μm, and scanning spacing of 50 μm. The density of the subordinate components under this reference can reach 99.15%, the surface hardness can reach 51.9 HRA, the yield strength can reach 550 MPa, the maximum machining error of the components is 4.73%, and the average surface roughness is 0.45 μm. Through dynamic hammering and high dynamic firing verification, SLM components meet the requirements for overload resistance. The results have proven that MEM technology can provide a new means for the processing of MEMS components applied in high dynamic environments. The parameters obtained in the conclusion can provide a design basis for the additive preparation of MEMS components.
基金financially supported by the National Natural Science Foundation of China(Nos.52074078 and 52374327)the Applied Fundamental Research Program of Liaoning Province,China(No.2023JH2/101600002)+3 种基金the Liaoning Provincial Natural Science Foundation,China(No.2022-YQ-09)the Shenyang Young Middle-Aged Scientific and Technological Innovation Talent Support Program,China(No.RC220491)the Liaoning Province Steel Industry-University-Research Innovation Alliance Cooperation Project of Bensteel Group,China(No.KJBLM202202)the Fundamental Research Funds for the Central Universities,China(Nos.N2201023 and N2325009)。
文摘In recent years,medium entropy alloys have become a research hotspot due to their excellent physical and chemical performances.By controlling reasonable elemental composition and processing parameters,the medium entropy alloys can exhibit similar properties to high entropy alloys and have lower costs.In this paper,a FeCoNi medium entropy alloy precursor was prepared via sol-gel and coprecipitation methods,respectively,and FeCoNi medium entropy alloys were prepared by carbothermal and hydrogen reduction.The phases and magnetic properties of FeCoNi medium entropy alloy were investigated.Results showed that FeCoNi medium entropy alloy was produced by carbothermal and hydrogen reduction at 1500℃.Some carbon was detected in the FeCoNi medium entropy alloy prepared by carbothermal reduction.The alloy prepared by hydrogen reduction was uniform and showed a relatively high purity.Moreover,the hydrogen reduction product exhibited better saturation magnetization and lower coercivity.
基金supported by the National Natural Science Foundation of China(Nos.51925103,52271149,52171159)the Innovation Program of Shanghai Municipal Education Commission(No.2021-01-07-00-09-E00114)+5 种基金the Natural Science Foundation of Shanghai(22ZR1422500)the Innovation Program of Shanghai Science and Technology(No.23520760700)the Aviation Foundation(No.2023Z0530S6004)the Fund of the State Key Laboratory of Solidification Processing in NWPU(No.SKLSP202221)the financial support from Program 173(No.2020-JCIQ-ZD-186-01)the Space Utilization System of China Manned Space Engineering(No.KJZ-YY-NCL08).
文摘Lightweight high/medium-entropy alloys(H/MEAs)possess attractive properties such as high strength-to-weight ratios,however,their limited room-temperature tensile ductility hinders their widespread engi-neering implementation,for instance in aerospace structural components.This work achieved a transfor-mative improvement of room-temperature tensile ductility in Ti-V-Zr-Nb MEAs with densities of 5.4-6.5 g/cm3,via ingenious composition modulation.Through the systematic co-adjustment of Ti and V contents,an intrinsic ductility mechanism was unveiled,manifested by a transition from predominant intergranular brittle fracture to pervasive ductile dimpled rupture.Notably,the modulated deformation mechanisms evolved from solitary slip toward collaborative multiple slip modes,without significantly compromising strength.Compared to equimolar Ti-V-Zr-Nb,a(Ti1.5V)3ZrNb composition demonstrated an impressive 360%improvement in elongation while sustaining a high yield strength of around 800 MPa.Increasing Ti and V not only purified the grain boundaries by reducing detrimental phases,but also tai-lored the deformation dislocation configurations.These insights expanded the applicability of lightweight HEAs to areas demanding combined high strength and ductility.
基金financial support from the National Natural Science Foundation of China(Nos.52233018 and 51831002)the China Baowu Low Carbon Metallurgy Innovation Foudation(No.BWLCF202213)。
文摘The influence of Nb-V microalloying on the hot deformation behavior and microstructures of medium Mn steel(MMS)was investigated by uniaxial hot compression tests.By establishing the constitutive equations for simulating the measured flow curves,we successfully constructed deformation activation energy(Q)maps and processing maps for identifying the region of flow instability.We concluded the following consequences of Nb-V alloying for MMS.(i)The critical strain increases and the increment diminishes with the increasing deformation temperature,suggesting that NbC precipitates more efficiently retard dynamic recrystallization(DRX)in MMS compared with solute Nb.(ii)The deformation activation energy of MMS is significantly increased and even higher than that of some reported high Mn steels,suggesting that its ability to retard DRX is greater than that of the high Mn content.(iii)The hot workability of MMS is improved by narrowing the hot processing window for the unstable flow stress,in which fine recrystallized and coarse unrecrystallized grains are present.
基金financial supports from National Natural Science Foundation of China(Grant Nos.U23A20368 and 62175006)Academic Excellence Foundation of BUAA for PhD Students.
文摘Due to the limitations of spatial bandwidth product and data transmission bandwidth,the field of view,resolution,and imaging speed constrain each other in an optical imaging system.Here,a fast-zoom and high-resolution sparse compound-eye camera(CEC)based on dual-end collaborative optimization is proposed,which provides a cost-effective way to break through the trade-off among the field of view,resolution,and imaging speed.In the optical end,a sparse CEC based on liquid lenses is designed,which can realize large-field-of-view imaging in real time,and fast zooming within 5 ms.In the computational end,a disturbed degradation model driven super-resolution network(DDMDSR-Net)is proposed to deal with complex image degradation issues in actual imaging situations,achieving high-robustness and high-fidelity resolution enhancement.Based on the proposed dual-end collaborative optimization framework,the angular resolution of the CEC can be enhanced from 71.6"to 26.0",which provides a solution to realize high-resolution imaging for array camera dispensing with high optical hardware complexity and data transmission bandwidth.Experiments verify the advantages of the CEC based on dual-end collaborative optimization in high-fidelity reconstruction of real scene images,kilometer-level long-distance detection,and dynamic imaging and precise recognition of targets of interest.
基金supported by the National Natural Science Foundation of China(Nos.52074228,52305420,and 51875470)the China Postdoctoral Science Foundation(No.2023M742830)。
文摘GH4169 joints manufactured by Linear Friction Welding(LFW)are subjected to tensile test and stair-case method to evaluate the High Cycle Fatigue(HCF)performance at 650℃.The yield and ultimate tensile strengths are 582 MPa and 820 MPa,respectively.The HCF strength of joint reaches 400 MPa,which is slightly lower than that of Base Metal(BM),indicating reliable quality of this type of joint.The microstructure observation results show that all cracks initiate at the inside of specimens and transfer into deeper region with decrease of external stress,and the crack initiation site is related with microhardness of matrix.The Electron Backscattered Diffraction(EBSD)results of the observed regions with different distances to fracture show that plastic deformation plays a key role in HCF,and the Schmid factor of most grains near fracture exceeds 0.4.In addition,the generation of twins plays a vital role in strain concentration release and coordinating plastic deformation among grains.
基金funded by the National Natural Science Foundation of China(Grant Nos.42072089 and 41530206)。
文摘Both fractional crystallization and fluid-melt-crystal interaction are involved in the formation of highly fractionated granites.This paper assessed those two processes using geochemistry of muscovite and tourmaline and bulkrock chemistry of multi-phase Wangxianling granitoids,South China.Compositional variations suggest the coarse-grained muscovite granite is produced from fractional crystallization of the two-mica granite whereas the fine-grained muscovite granite represents a distinct magma pulse.Progressive fractionation of quartz,feldspar and biotite leads to elevated boron and aluminum content in melt which promoted muscovite and tourmaline to crystallize,which promotes two-mica granite evolving towards tourmaline-bearing muscovite granite.Fluid-melt-crystal interaction occurred at the magmatichydrothermal transitional stage and resulted in the textural and chemical zonings of tourmaline and muscovite in finegrained muscovite granite.The rims of both tourmaline and muscovite are characterized by the enrichment of fluid mobile elements such as Li,Mn,Cs and Zn and heavierδ^(11)B values of the tourmaline rims(-15.0‰to-13.6‰)compared to cores(-15.7‰to-14.3‰).Meanwhile,significant M-type REE tetrad effects(TE_(1,3)=1.07-1.18)and low K/Rb ratios(48-52)also correspond to fluid-melt-crystal interaction.This study shows zoned muscovite and tourmaline can be excellent tracers of fractional crystallization and late-stage fluid-melt-crystal interaction in highly evolved magmatic systems.
基金supported by the National Key Research and Development Program of China(Grant No.2022YFF0609000)National Natural Science Foundation of China(Grant Nos.52171034 and 52101037)Postdoctoral Fellowship Program of CPSFara(No.GZB20230944).
文摘Up-and-coming high-temperature materials,refractory high entropy alloys,are suffering from lower oxidation resistance,restricting their applications in the aerospace field.In this study,two novel treatments of Al-deposited and remelted were developed to refine the microstructure and enhance the oxidation resistance of refractory high entropy alloy using electron beam freeform fabrication(EBF3).Finer and short-range ordering structures were observed in the remelted sample,whereas the Al-deposited sample showcased the formation of silicide and intermetallic phases.High-temperature cyclic and isothermal oxidation tests at 1000℃ were carried out.The total weight gain after 60 h of cyclic oxidation decreased by 17.49%and 30.46%for the remelted and deposited samples,respectively,compared to the as-cast state.Oxidation kinetics reveal an evident lower mass gain and oxidation rate in the treated samples.A multilayer oxide consisting of TiO_(2)+Al_(2)O_(3)+SiO_(2)+AlNbO_(4) was studied for its excellent oxidation resistance.The oxidation behavior of rutile,corundum and other oxides was analyzed using first principles calculations and chemical defect analysis.Overall,this research,which introduces novel treatments,offers promising insights for enhancing the inherent oxidation resistance of refractory high entropy alloys.
基金financially supported by the Beijing Natural Science Foundation,China (No.JQ21028)the National Natural Science Foundation of China (Nos.52311530070,52278326,and 52004015)+2 种基金the Major National Science and Technology Project for Deep Earth,China (No.2024ZD1003805)the Project from PetroChina RIPED:the Study on the evolution law of Mineral Structure and Rock Mechanical Properties Under Ultra-High Temperature Conditions (No.2022-KFKT-02)the Fundamental Research Funds for the Central Universities of China (No.FRF-IDRY-20-003,Interdisciplinary Research Project for Young Teachers of USTB)。
文摘Low-to medium-maturity oil shale resources display substantial reserves, offering promising prospects for in-situ conversion inChina. Investigating the evolution of the mechanical properties of the reservoir and caprock under in-situ high-temperature and confine-ment conditions is of considerable importance. Compared to conventional mechanical experiments on rock samples after high-temperat-ure treatment, in-situ high-temperature experiments can more accurately characterize the behavior of rocks in practical engineering,thereby providing a more realistic reflection of their mechanical properties. In this study, an in-situ high-temperature triaxial compressiontesting machine is developed to conduct in-situ compression tests on sandstone at different temperatures(25, 200, 400, 500, and 650℃)and confining pressures(0, 10, and 20 MPa). Based on the experimental results, the temperature-dependent changes in compressivestrength, peak strain, elastic modulus, Poisson's ratio, cohesion, and internal friction angle are thoroughly analyzed and discussed. Resultsindicate that the mass of sandstone gradually decreases as the temperature increases. The thermal conductivity and thermal diffusivity ofsandstone exhibit a linear relationship with temperature. Peak stress decreases as the temperature rises, while it increases with higher con-fining pressures. Notably, the influence of confining pressure on peak stress diminishes at higher temperatures. Additionally, as the tem-perature rises, the Poisson's ratio of sandstone decreases. The internal friction angle also decreases with increasing temperature, with 400℃ acting as the threshold temperature. Interestingly, under uniaxial conditions, the damage stress of sandstone is less affected by tem-perature. However, when the confining pressure is 10 or 20 MPa, the damage stress decreases as the temperature increases. This study en-hances our understanding of the influence of in-situ high-temperature and confinement conditions on the mechanical properties of sand-stone strata. The study also provides valuable references and experimental data that support the development of low-to medium-maturityoil shale resources.
基金National Natural Science Foundation of China(52104294)Fundamental Research Funds for the Central Universities(FRF-TP-19-079A1)。
文摘The soaring demand for smart portable electronics and electric vehicles is propelling the advancements in high-energy–density lithium-ion batteries.Lithium manganese iron phosphate(LiMn_(x)Fe_(1-x)PO_(4))has garnered significant attention as a promising positive electrode material for lithium-ion batteries due to its advantages of low cost,high safety,long cycle life,high voltage,good high-temperature performance,and high energy density.Although LiMn_(x)Fe_(1-x)PO_(4)has made significant breakthroughs in the past few decades,there are still facing great challenges in poor electronic conductivity and Li-ion diffusion,manganese dissolution affecting battery cycling performance,as well as low tap density.This review systematically summarizes the reaction mechanisms,various synthesis methods,and electrochemical properties of LiMn_(x)Fe_(1-x)PO_(4)to analyze reaction processes accurately and guide material preparation.Later,the main challenges currently faced are concluded,and the corresponding various modification strategies are discussed to enhance the reaction kinetics and electrochemical performance of LiMn_(x)Fe_(1-x)PO_(4),including multi-scale particle regulation,heteroatom doping,surface coating,as well as microscopic morphology design.Finally,in view of the current research challenges faced by intrinsic reaction processes,kinetics,and energy storage applications,the promising research directions are anticipated.More importantly,it is expected to provide key insights into the development of high-performance and stable LiMn_(x)Fe_(1-x)PO_(4)materials,to achieve practical energy storage requirements.
基金supported by the CNPC Science and Technology Major Project of the Fourteenth Five-Year Plan(2021DJ0101)the National Natural Science Foundation of China(U19B600302,41872148)。
文摘The Early Cambrian Yuertusi Formation(Є_(1)y)in the Tarim Basin of China deposits a continuously developed suite of organic-rich black mudstones,which constitute an important source of oil and gas reservoirs in the Paleozoic.However,its hydrocarbon generation and evolution characteristics and resource potential have long been constrained by deeply buried strata and previous research.In this paper,based on the newly obtained ultra-deep well drilling data,the hydrocarbon generation and expulsion model ofЄ_(1)y shale was established by using data-driven Monte Carlo simulation,upon which the hydrocarbon generation,expulsion,and retention amounts were calculated by using the diagenetic method.The research indicates that theЄ_(1)y shale reaches the hydrocarbon generation and expulsion threshold at equivalent vitrinite reflectances of 0.46%and 0.72%,respectively.The cumulative hydrocarbon generation is 68.88×10^(10)t,the cumulative hydrocarbon expulsion is 35.59×10^(10)t,and the cumulative residual hydrocarbon is 33.29×10^(10)t.This paper systematically and quantitatively calculates the hydrocarbon expulsion at various key geological periods for theЄ_(1)y source rocks in the study area for the first time,more precisely confirming that the black shale of theЄ_(1)y is the most significant source rock contributing to the marine oil and gas resources in the Tarim Basin,filling the gap in hydrocarbon expulsion calculation in the study area,and providing an important basis for the formation and distribution of Paleozoic hydrocarbon reservoirs.The prospect of deep ultra-deep oil and gas exploration in the Tarim Basin is promising.Especially,the large area of dolomite reservoirs under the Cambrian salt and source rock interiors are the key breakthrough targets for the next exploration in the Tarim Basin.
基金supported by the National Natural Science Foundation of China(Nos.22208221,22178221)the Natural Science Foundation of Guangdong Province(Nos.2024A1515011078,2024A1515011507)+1 种基金the Shenzhen Science and Technology Program(Nos.JCYJ20220818095805012,JCYJ20230808105109019)the Start-up Research Funding of Shenzhen University(No.868-000001032522).
文摘The deterioration of aqueous zinc-ion batteries(AZIBs)is confronted with challenges such as unregulated Zn^(2+)diffusion,dendrite growth and severe decay in battery performance under harsh environments.Here,a design concept of eutectic electrolyte is presented by mixing long chain polymer molecules,polyethylene glycol dimethyl ether(PEGDME),with H_(2)O based on zinc trifluoromethyl sulfonate(Zn(OTf)2),to reconstruct the Zn^(2+)solvated structure and in situ modified the adsorption layer on Zn electrode surface.Molecular dynamics simulations(MD),density functional theory(DFT)calculations were combined with experiment to prove that the long-chain polymer-PEGDME could effectively reduce side reactions,change the solvation structure of the electrolyte and priority absorbed on Zn(002),achieving a stable dendrite-free Zn anode.Due to the comprehensive regulation of solvation structure and zinc deposition by PEGDME,it can stably cycle for over 3200 h at room temperature at 0.5 mA/cm^(2)and 0.5 mAh/cm^(2).Even at high-temperature environments of 60℃,it can steadily work for more than 800 cycles(1600 h).Improved cyclic stability and rate performance of aqueous Zn‖VO_(2)batteries in modified electrolyte were also achieved at both room and high temperatures.Beyond that,the demonstration of stable and high-capacity Zn‖VO_(2)pouch cells also implies its practical application.
