The recycling and reutilization of spent lithium-ion batteries(LIBs)have become an important measure to alleviate problems like resource scarcity and environmental pollution.Although some progress has been made,batter...The recycling and reutilization of spent lithium-ion batteries(LIBs)have become an important measure to alleviate problems like resource scarcity and environmental pollution.Although some progress has been made,battery recycling technology still faces challenges in terms of efficiency,effectiveness and environmental sustainability.This review aims to systematically review and analyze the current status of spent LIB recycling,and conduct a detailed comparison and evaluation of different recycling processes.In addition,this review introduces emerging recycling techniques,including deep eutectic solvents,molten salt roasting,and direct regeneration,with the intent of enhancing recycling efficiency and diminishing environmental repercussions.Furthermore,to increase the added value of recycled materials,this review proposes the concept of upgrading recycled materials into high value-added functional materials,such as catalysts,adsorbents,and graphene.Through life cycle assessment,the paper also explores the economic and environmental impacts of current battery recycling and highlights the importance that future recycling technologies should achieve a balance between recycling efficiency,economics and environmental benefits.Finally,this review outlines the opportunities and challenges of recycling key materials for next-generation batteries,and proposes relevant policy recommendations to promote the green and sustainable development of batteries,circular economy,and ecological civilization.展开更多
The interface mechanism between catalyst and carbon substrate has been the focus of research.In this paper,the FeCo alloy embedded N,S co-doped carbon substrate bifunctional catalyst(FeCo/S-NC)is obtained by a simple ...The interface mechanism between catalyst and carbon substrate has been the focus of research.In this paper,the FeCo alloy embedded N,S co-doped carbon substrate bifunctional catalyst(FeCo/S-NC)is obtained by a simple one-step pyrolysis strategy.The experimental results and density functional theory(DFT)calculation show that the formation of FeCo alloy is conducive to promoting electron transfer,and the introduction of S atom can enhance the interaction between FeCo alloy and carbon substrate,thus inhibiting the migration and agglomeration of particles on the surface of carbon material.The FeCo/SNC catalysts show outstanding performance for oxygen reduction reaction(ORR)and oxygen evolution reaction(OER).FeCo/S-NC shows a high half-wave potential(E_(1/2)=0.8823 V)for ORR and a low overpotential at 10 mA cm^(-2)(E_(j=10)=299 mV)for OER.In addition,compared with Pt/C+RuO_(2) assembled Zn-air battery(ZAB),the FeCo/S-NC assembled ZAB exhibits a larger power density(198.8 mW cm^(-2)),a higher specific capacity(786.1 mA h g_(zn)~(-1)),and ultra-stable cycle performance.These results confirm that the optimized composition and the interfacial interaction between catalyst and carbon substrate synergistically enhance the electrochemical performance.展开更多
The infamous type Ⅳ failure within the fine-grained heat-affected zone (FGHAZ) in G115 steel weldments seriously threatens the safe operation of ultra-supercritical (USC) power plants.In this work,the traditional the...The infamous type Ⅳ failure within the fine-grained heat-affected zone (FGHAZ) in G115 steel weldments seriously threatens the safe operation of ultra-supercritical (USC) power plants.In this work,the traditional thermo-mechanical treatment was modified via the replacement of hot-rolling with cold rolling,i.e.,normalizing,cold rolling,and tempering (NCT),which was developed to improve the creep strength of the FGHAZ in G115 steel weldments.The NCT treatment effectively promoted the dissolution of preformed M_(23)C_(6)particles and relieved the boundary segregation of C and Cr during welding thermal cycling,which accelerated the dispersed reprecipitation of M_(23)C_(6) particles within the fresh reaustenitized grains during post-weld heat treatment.In addition,the precipitation of Cu-rich phases and MX particles was promoted evidently due to the deformation-induced dislocations.As a result,the interacting actions between precipitates,dislocations,and boundaries during creep were reinforced considerably.Following this strategy,the creep rupture life of the FGHAZ in G115 steel weldments can be prolonged by 18.6%,which can further push the application of G115 steel in USC power plants.展开更多
03-type layered metal oxides hold great promise for sodium-ion batteries cathodes owing to their energy density advantage.However,the severe irreversible phase transition and sluggish Na^(+)diffusion kinetics pose sig...03-type layered metal oxides hold great promise for sodium-ion batteries cathodes owing to their energy density advantage.However,the severe irreversible phase transition and sluggish Na^(+)diffusion kinetics pose significant challenges to achieve high-performance layered cathodes.Herein,a boron-doped03-type high entropy oxide Na(Fe_(0.2)Co_(0.15)Cu_(0.05)Ni_(0.2)Mn_(0.2)Ti_(0.2))B_(0.02)O_(2)(NFCCNMT-B_(0.02))is designed and the covalent B-O bonds with high entropy configuration ensure a robust layered structure.The obtained cathode NFCCNMT-B_(0.02)exhibits impressive cycling performance(capacity retention of 95%and 82%after100 cycles and 300 cycles at 1 and 10 C,respectively)and outstanding rate capability(capacity of 83 mAh g^(-1)at 10 C).Furthermore,the NFCCNMT-B_(0.02)demonstrates a superior wide-temperature performance,maintaining the same capacity level(113,4 mAh g^(-1)@-20℃,121 mAh g^(-1)@25℃,and 119 mAh g^(-1)@60℃)and superior cycle stability(90%capacity retention after 100 cycles at 1 C at-20℃).The high-entropy configuration design with boron doping strategy contributes to the excellent sodium-ion storage performance.The high-entropy configuration design effectively suppresses irreversible phase transitions accompanied by small volume changes(ΔV=0.65 A3).B ions doping expands the Na layer distance and enlarges the P3 phase region,thereby enhancing Na^(+)diffusion kinetics.This work offers valuable insights into design of high-performance layered cathodes for sodium-ion batteries operating across a wide temperature.展开更多
High-entropy materials(HEMs),which are newly manufactured compounds that contain five or more metal cations,can be a platform with desired properties,including improved electrocatalytic performance owing to the inhere...High-entropy materials(HEMs),which are newly manufactured compounds that contain five or more metal cations,can be a platform with desired properties,including improved electrocatalytic performance owing to the inherent complexity.Here,a strain engineering methodology is proposed to design transition-metal-based HEM by Li manipulation(LiTM)with tunable lattice strain,thus tailoring the electronic structure and boosting electrocatalytic performance.As confirmed by the experiments and calculation results,tensile strain in the LiTM after Li manipulation can optimize the d-band center and increase the electrical conductivity.Accordingly,the asprepared LiTM-25 demonstrates optimized oxygen evolution reaction and hydrogen evolution reaction activity in alkaline saline water,requiring ultralow overpotentials of 265 and 42 mV at 10 mA cm−2,respectively.More strikingly,LiTM-25 retains 94.6%activity after 80 h of a durability test when assembled as an anion-exchange membrane water electrolyzer.Finally,in order to show the general efficacy of strain engineering,we incorporate Li into electrocatalysts with higher entropies as well.展开更多
Rechargeable metal-ion batteries, such as lithium-ion batteries(LIBs) and sodium-ion batteries(SIBs),have raised more attention because of the large demand for energy storage solutions. Undoubtedly, electrode material...Rechargeable metal-ion batteries, such as lithium-ion batteries(LIBs) and sodium-ion batteries(SIBs),have raised more attention because of the large demand for energy storage solutions. Undoubtedly, electrode materials and electrolytes are key parts of batteries, exhibiting critical influence on the reversible capacity and span life of the metal-ion battery. Nonetheless, researchers commonly express concerns regarding the stability of both electrodes and electrolytes. Given its commendable stability attributes,high-entropy materials have garnered widespread acclaim and have been applied in many fields since their inception, notably in energy storage. However, while certain high-entropy designs have achieved substantial breakthroughs, some have failed to meet anticipated outcomes within the high energy density energy storage materials. Moreover, there is a lack of comprehensive summary research on the corresponding mechanisms and design principles of high-entropy designs. This review examines the current high-entropy designs for cathodes, anodes, and electrolytes, aiming to summarize the design principle,potential mechanisms, and electrochemical performance. We focus on their structural characteristics,interface characteristics, and prospective development trends. At last, we provide a fair evaluation along-side succinct development suggestions.展开更多
Metal(Li,Na,K,Al)-ion batteries and lithium-sulfur and lithium-tellurium batteries are gaining recognition for their eco-friendly characteristics,substantial energy density,and sustainable attributes.However,the overa...Metal(Li,Na,K,Al)-ion batteries and lithium-sulfur and lithium-tellurium batteries are gaining recognition for their eco-friendly characteristics,substantial energy density,and sustainable attributes.However,the overall performance of rechargeable batteries heavily depends on their electrode materials.Transition metal tellurides have recently gained significant attention due to their high electrical conductivity and density.Cobalt telluride has received the most extensive research due to its catalytic activity,unique magnetic properties,and diverse composition and crystal structure.Nevertheless,its limited conductivity and significant volume variation contribute to electrode structural deterioration and rapid capacity decline.This review comprehensively summarizes recent advances in rational design and synthesis of modified cobalt telluride-based electrodes,encompassing defect engineering(Te vacancies,cation vacancies,heterointerfaces,and homogeneous interfaces)and composite engineering(derived carbon from precursors,carbon fibers,Mxene,graphene nanosheets,etc.).Particularly,the intricate evolution mechanisms of the conversion reaction process during cycling are elucidated.Furthermore,these modified strategies applied to other transitional metal tellurides,such as iron telluride,nickel telluride,zinc telluride,copper telluride,molybdenum telluride,etc.,are also thoroughly summarized.Additionally,their application extends to emerging aqueous zinc-ion batteries.Finally,potential challenges and prospects are discussed to further propel the development of transition metal tellurides electrode materials for next-generation rechargeable batteries.展开更多
With the development of big data and social computing,large-scale group decisionmaking(LGDM)is nowmerging with social networks.Using social network analysis(SNA),this study proposes an LGDM consensus model that consid...With the development of big data and social computing,large-scale group decisionmaking(LGDM)is nowmerging with social networks.Using social network analysis(SNA),this study proposes an LGDM consensus model that considers the trust relationship among decisionmakers(DMs).In the process of consensusmeasurement:the social network is constructed according to the social relationship among DMs,and the Louvain method is introduced to classify social networks to form subgroups.In this study,the weights of each decision maker and each subgroup are computed by comprehensive network weights and trust weights.In the process of consensus improvement:A feedback mechanism with four identification and two direction rules is designed to guide the consensus of the improvement process.Based on the trust relationship among DMs,the preferences are modified,and the corresponding social network is updated to accelerate the consensus.Compared with the previous research,the proposedmodel not only allows the subgroups to be reconstructed and updated during the adjustment process,but also improves the accuracy of the adjustment by the feedbackmechanism.Finally,an example analysis is conducted to verify the effectiveness and flexibility of the proposed method.Moreover,compared with previous studies,the superiority of the proposed method in solving the LGDM problem is highlighted.展开更多
Inconel 718 is the most popular nickel-based superalloy and is extensively used in aerospace,automotive,and energy indus-tries owing to its extraordinary thermomechanical properties.The effects of different two-step s...Inconel 718 is the most popular nickel-based superalloy and is extensively used in aerospace,automotive,and energy indus-tries owing to its extraordinary thermomechanical properties.The effects of different two-step solid solution treatments on microstructure andδphase precipitation of Inconel 718 alloy were studied,and the transformation mechanism fromγ″metastable phase toδphase was clarified.The precipitates were statistically analyzed by X-ray diffractometry.The results show that theδphase content firstly increased,and then decreased with the temperature of the second-step solid solution.The changes in microstructure andδphase were studied by scanning electron microscopy and transmission electron microscopy.An intragranularδphase formed in Inconel 718 alloy at the second-[100]_(δ)[011]γ step solid solution temperature of 925℃,and its orientation relationship withγmatrix was determined as//and(010)_(δ)//(111)γ.Furthermore,the Vickers hardness of different heat treatment samples was measured,and the sample treated by second-step solid solution at 1010℃ reached the maximum hardness of HV 446.84.展开更多
Based on the observation and analysis of cores and thin sections,and combined with cathodoluminescence,laser Raman,fluid inclusions,and in-situ LA-ICP-MS U-Pb dating,the genetic mechanism and petroleum geological sign...Based on the observation and analysis of cores and thin sections,and combined with cathodoluminescence,laser Raman,fluid inclusions,and in-situ LA-ICP-MS U-Pb dating,the genetic mechanism and petroleum geological significance of calcite veins in shales of the Cretaceous Qingshankou Formation in the Songliao Basin were investigated.Macroscopically,the calcite veins are bedding parallel,and show lenticular,S-shaped,cone-in-cone and pinnate structures.Microscopically,they can be divided into syntaxial blocky or columnar calcite veins and antitaxial fibrous calcite veins.The aqueous fluid inclusions in blocky calcite veins have a homogenization temperature of 132.5–145.1℃,the in-situ U-Pb dating age of blocky calcite veins is(69.9±5.2)Ma,suggesting that the middle maturity period of source rocks and the conventional oil formation period in the Qingshankou Formation are the sedimentary period of Mingshui Formation in Late Cretaceous.The aqueous fluid inclusions in fibrous calcite veins with the homogenization temperature of 141.2–157.4℃,yields the U-Pb age of(44.7±6.9)Ma,indicating that the middle-high maturity period of source rocks and the Gulong shale oil formation period in the Qingshankou Formation are the sedimentary period of Paleocene Yi'an Formaiton.The syntaxial blocky or columnar calcite veins were formed sensitively to the diagenetic evolution and hydrocarbon generation,mainly in three stages(fracture opening,vein-forming fluid filling,and vein growth).Tectonic extrusion activities and fluid overpressure are induction factors for the formation of fractures,and vein-forming fluid flows mainly as diffusion in a short distance.These veins generally follow a competitive growth mode.The antitaxial fibrous calcite veins were formed under the driving of the force of crystallization in a non-competitive growth environment.It is considered that the calcite veins in organic-rich shale of the Qingshankou Formation in the study area has important implications for local tectonic activities,fluid overpressure,hydrocarbon generation and expulsion,and diagenesis-hydrocarbon accumulation dating of the Songliao Basin.展开更多
AIM:To analyze the distribution of fibrovascular proliferative membranes(FVPMs)in proliferative diabetic retinopathy(PDR)patients that treated with pars plana vitrectomy(PPV),and to evaluate the outcomes separately.ME...AIM:To analyze the distribution of fibrovascular proliferative membranes(FVPMs)in proliferative diabetic retinopathy(PDR)patients that treated with pars plana vitrectomy(PPV),and to evaluate the outcomes separately.METHODS:This was a retrospective and cross-sectional study.Consecutive 25-gauge(25-G)PPV cases operated for PDR from May 2018 to April 2020.According to the FVPMs images outlined after operations,subjects were assigned into three groups:arcade type group,juxtapapillary type group,and central type group.All patients were followed up for over one year.General characteristics,operation-related variables,postoperative parameters and complications were recorded.RESULTS:Among 103 eyes recruited,the FVPMs distribution of nasotemporal and inferiosuperioral was significantly different(both P<0.01),with 95(92.23%)FVPMs located in the nasal quadrants,and 74(71.84%)in the inferior.The eyes with a central FVPM required the longest operation time,with silicon oil used in most patients,generally combined with tractional retinal detachment(RD)and rhegmatogenous RD,the worst postoperative bestcorrected visual acuity(BCVA)and the highest rates of recurrent RD(all P<0.05).FVPM type,age of onset diabetes mellitus,preoperative BCVA,and combined with tractional RD and rhegmatogenous RD were significantly associated with BCVA improvement(all P<0.05).Compared with the central type group,the arcade type group had higher rates of BCVA improvement.CONCLUSION:FVPMs are more commonly found in the nasal and inferior mid-peripheral retina in addition to the area of arcade vessels.Performing 25-G PPV for treating PDR eyes with central FVPM have relatively worse prognosis.展开更多
Supercapacitors known as typical electrochemical capacitors have been considered as one of the most promising candidates of energy storage systems owing to their advantages such as high-power density,long life span an...Supercapacitors known as typical electrochemical capacitors have been considered as one of the most promising candidates of energy storage systems owing to their advantages such as high-power density,long life span and lower production cost.The electrode materials play a crucial role on properties of supercapacitors.Hence,many researches have been focused on the development of novel electrode materials for high-performance supercapacitors.NiCo_2O_4as supercapacitor electrode material has drawn more and more attentions in recent years due to its outstanding advantages,such as high theoretical capacity,low cost,natural abundance and easy of synthesis.However,the NiCo_2O_4always suffer from severe capacity deterioration because of the low electrical conductivity and small surface area.Hence,it is necessary to systematically and comprehensively summarize the progress in understanding and modifying NiCo_2O_4-based materials from various aspects.In this review,the structure and synthesis method of NiCo_2O_4-based materials are discussed in detail.And then,the major goal of this review is to highlight new progress in using proposed strategies to improve the cycling stability and rate capacity of NiCo_2O_4-based materials,including synthesis,control of special morphologies and design of composite materials.Finally,an insight into the future research and development of Ni Co_2O_4-based materials for supercapacitors is prospected.展开更多
The mineralogical phase transformation of a low-grade nickel laterite ore during pre-roasting process and the extraction of silicon during alkaline leaching process were investigated.The results indicate that the reac...The mineralogical phase transformation of a low-grade nickel laterite ore during pre-roasting process and the extraction of silicon during alkaline leaching process were investigated.The results indicate that the reaction activity of nickel ores is effectively improved by pre-roasting at650°C for2h,because of the transformation of lizardite into magnesium olivine and protoenstatite.When finely ground ore samples(44-61μm)pre-roasted firstly react with sodium hydroxide solution(60g/L)with a solid/liquid ratio of1:5at140°C for120min,the extraction of silicon can reach89.89%,and the other valuable elements of magnesium,iron and nickel are accumulated in the solid residues.The leaching kinetics of nickel laterite ore can be described successfully by the diffusion through the product layer control model.The activation energy is calculated to be11.63kJ/mol and the kinetics equation can be expressed as1-3(1-x)2/3+2(1-x)=13.53×10-2exp[-11.63/(RT)]t.展开更多
In this paper,we investigate formation tracking control of autonomous underwater vehicles(AUVs)with model parameter uncertainties and external disturbances.The external disturbances due to the wind,waves,and ocean cur...In this paper,we investigate formation tracking control of autonomous underwater vehicles(AUVs)with model parameter uncertainties and external disturbances.The external disturbances due to the wind,waves,and ocean currents are combined with the model parameter uncertainties as a compound disturbance.Then a disturbance observer(DO)is introduced to estimate the compound disturbance,which can be achieved within a finite time independent of the initial estimation error.Based on a DO,a novel fixed-time sliding control scheme is developed,by which the follower vehicle can track the leader vehicle with all the states globally stabilized within a given settling time.The effectiveness and performance of the method are demonstrated by numerical simulations.展开更多
A novel process was proposed for the utilization of potash feldspar by roasting in the presence of sodium carbonate. The effects of roasting temperature, granularity, molar ratio of sodium carbonate to potash feldspar...A novel process was proposed for the utilization of potash feldspar by roasting in the presence of sodium carbonate. The effects of roasting temperature, granularity, molar ratio of sodium carbonate to potash feldspar and roasting time on the silica extraction rate were investigated. Under the optimal roasting conditions, the silica extraction rate was 98%. The optimal conditions, determined using an orthogonal experiment, were found to be roasting temperature of 875 A degrees C, potash feldspar granularity of 74-89 mu m, molar ratio of sodium carbonate to potash feldspar of 1.2:1, and roasting time of 80 min. The kinetics of potash feldspar roasting in the presence of sodium carbonate was described by the shrinking core model and the reaction rate was found to be controlled by the chemical reaction at the particle surface. According to the Arrhenius expression, the activation energy was 164.99 kJ/mol, and the process could be expressed as [1-(1-alpha)(1/3)]=2.66x10(5) exp[-164990/(RT)] t.展开更多
Ultrafine nano-scale Cu2Sb alloy confined in a three-dimensional porous carbon was synthesized using NaCl template-assisted vacuum freeze-drying followed by high-temperature sintering and was evaluated as an anode for...Ultrafine nano-scale Cu2Sb alloy confined in a three-dimensional porous carbon was synthesized using NaCl template-assisted vacuum freeze-drying followed by high-temperature sintering and was evaluated as an anode for sodium-ion batteries(SIBs)and potassium-ion batteries(PIBs).The alloy exerts excellent cycling durability(the capacity can be maintained at 328.3 mA·h·g^(-1) after 100 cycles for SIBs and 260 mA·h·g^(-1) for PIBs)and rate capability(199 mA·h·g^(-1) at 5 A·g^(-1) for SIBs and 148 mA·h·g^(-1) at 5 A·g^(-1) for PIBs)because of the smooth electron transport path,fast Na/K ion diffusion rate,and restricted volume changes from the synergistic effect of three-dimensional porous carbon networks and the ultrafine bimetallic nanoalloy.This study provides an ingenious design route and a simple preparation method toward exploring a high-property electrode for K-ion and Na-ion batteries,and it also introduces broad application prospects for other electrochemical applications.展开更多
Fe-Mn based layer oxides cathode materials have attracted widespread attention as a potential candidate for sodium-ion batteries(SIBs)owing to the earth abundance,cost-effectiveness and acceptable specific capacity.Ho...Fe-Mn based layer oxides cathode materials have attracted widespread attention as a potential candidate for sodium-ion batteries(SIBs)owing to the earth abundance,cost-effectiveness and acceptable specific capacity.However,the irreversible phase transition often brings rapid capacity decay,which seriously hinders the practical application in large-scale energy storage.Herein,we design a nickel-doped Na_(0.70)Fe_(0.10)Cu_(0.20)Ni_(0.05)Mn_(0.65)O_(2)(NFCNM-0.05)cathode material of SIBs with activated anionic redox reaction,and then inhibit the harmful phase transition.The ex-situ X-ray diffraction patterns demonstrate the NFCNM-0.05 always keeps the P2 phase during the sodiation/desodiation process,indicating a high structure stability.The ex-situ X-ray photoelectron spectroscopy implies the redox reactions between O2-and O-occur in the charging process,which offers extra specific capacity.Thus,the NFCNM-0.05 electrode delivers a high initial discharge capacity of 148 mA h g-1and remains a prominent cycling stability with an excellent capacity retention of 95.9%after 200 cycles at 1 C.In addition,the electrochemical impedance spectroscopy and galvanostatic intermittent titration technique show the NFCNM-0.05 electrode possesses fast ion diffusion ability,which is beneficial for the enhancement of rate performance.Even at 10 C,the NFCNM-0.05 can offer a reversible discharge capacity of 81 mA h g-1.DFT calculation demonstrates the doping of appropriate amount of Ni ions is benefit for the enhancement of the electrochemical performance of the layer oxides.This work provides an effective strategy to enhance the electrochemical performance of Fe-Mn based cathode materials of SIBs.展开更多
Li_(5)Cr_(7)Ti_(6)O_(25) is regarded as a promising anode material for Li-ion batteries(LIBs)because of its low cost and high theoretical capacity.However,the inherently poor conductivity significantly limits the enha...Li_(5)Cr_(7)Ti_(6)O_(25) is regarded as a promising anode material for Li-ion batteries(LIBs)because of its low cost and high theoretical capacity.However,the inherently poor conductivity significantly limits the enhancement of its rate capability and cycling stability,especially at high current densities.In this work,we construct one-dimensional Li_(5)Cr_(7)Ti_(6)O_(25)/C nanofibers by electrospinning method to enhance the kinetic,which realizes high cycling stability.Carbon coating enhances the structure stability,insertion/extraction reversibility of Li-ions and electrochemical reaction activity,and facilitates the transfer of Li-ions.Benefited from the unique architecture and component,the Li_(5)Cr_(7)Ti_(6)O_(25)/C(6.6 wt%)nanofiber shows an excellent rate capability with a reversible de-lithiation capacity of 370.8,290.6,269.2,254.3 and 244.9 m Ah g^(-1) at 200,300,500,800 and 1000 m A g^(-1),respectively.Even at a higher current density of 1 A g^(-1),Li_(5)Cr_(7)Ti_(6)O_(25)/C(6.6 wt%)nanofiber shows high cycling stability with an initial de-lithiation capacity of 237.8 m Ah g^(-1) and a capacity retention rate of about 84%after 500 cycles.The density functional theory calculation result confirms that the introduction of carbon on the surface of Li_(5)Cr_(7)Ti_(6)O_(25) changes the total density of states of Li_(5)Cr_(7)Ti_(6)O_(25),and thus improves electronic conductivity of the composite,resulting in a good electrochemical performance of Li_(5)Cr_(7)Ti_(6)O_(25)/C nanofibers.Li_(5)Cr_(7)Ti_(6)O_(25)/C nanofibers indicate a great potential as an anode material for the next generation of high-performance LIBs.展开更多
To investigate cutting performance in the helical milling of carbon fiber reinforced polymer(CFRP),experiments were conducted with unidirectional laminates.The results show that the influence of cutting parameters is ...To investigate cutting performance in the helical milling of carbon fiber reinforced polymer(CFRP),experiments were conducted with unidirectional laminates.The results show that the influence of cutting parameters is very significant in the helical milling process. The axial force increases with the increase of cutting speed, which is below 95 m/min; otherwise, the axial force decreases with the increase of cutting speed. The resultant force always increases when cutting speed increases; with the increase of tangential and axial feed rates, cutting forces increase gradually. In addition, damage rings can appear in certain regions of the entry edges; therefore, the relationship between machining performance(cutting forces and holemaking quality) and cutting parameters is established using the nonlinear fitting methodology. Thus, three cutting parameters in the helical milling of CFRP, under the steady state, are optimized based on the multi-objective genetic algorithm, including material removal rate and machining performance. Finally, experiments were carried out to prove the validity of optimized cutting parameters.展开更多
A novel process was proposed for recovering nickel from nickeliferous laterite ores.First of all,silicon and magnesium were removed from lateritic ore by high concentration sodium hydroxide leaching and carbonation re...A novel process was proposed for recovering nickel from nickeliferous laterite ores.First of all,silicon and magnesium were removed from lateritic ore by high concentration sodium hydroxide leaching and carbonation respectively,so as to enrich nickel. Then the method of ammonia carbonate leaching was adopted to recover nickel from the carbonized slag,and the remaining residue was used as a raw material for recovering iron.The effects of temperature,ammonia carbonate concentration,liquid/solid ratio and stirring speed on the recovery of nickel were examined.When the leached residue reacted with ammonia carbonate(6 mol·L- 1)in a ratio of liquid-to-solid of 5-1 at 60℃for 150 min at the stirring speed of 300 r·min- 1,approximate more than 95%nickel was recovered.During the whole process,there was no contamination produced and the chemical raw materials were recycled,thus the process was a green technology that having good social benefit.展开更多
基金financially supported by the National Natural Science Foundation of China(NSFC)(52274295)the Natural Science Foundation of Hebei Province(E2020501001,E2021501029,A2021501007,E2022501028,E2022501029)+5 种基金the Natural Science Foundation-Steel,the Iron Foundation of Hebei Province(No.E2022501030)the Performance subsidy fund for Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province(22567627H)the Science and Technology Project of Hebei Education Department(ZD2022158)the Central Guided Local Science and Technology Development Fund Project of Hebei province(226Z4401G)the China Scholarship Council(No.202206080061,202206050119)the 2023 Hebei Provincial Postgraduate Student Innovation Ability training funding project(CXZZSS2023195)。
文摘The recycling and reutilization of spent lithium-ion batteries(LIBs)have become an important measure to alleviate problems like resource scarcity and environmental pollution.Although some progress has been made,battery recycling technology still faces challenges in terms of efficiency,effectiveness and environmental sustainability.This review aims to systematically review and analyze the current status of spent LIB recycling,and conduct a detailed comparison and evaluation of different recycling processes.In addition,this review introduces emerging recycling techniques,including deep eutectic solvents,molten salt roasting,and direct regeneration,with the intent of enhancing recycling efficiency and diminishing environmental repercussions.Furthermore,to increase the added value of recycled materials,this review proposes the concept of upgrading recycled materials into high value-added functional materials,such as catalysts,adsorbents,and graphene.Through life cycle assessment,the paper also explores the economic and environmental impacts of current battery recycling and highlights the importance that future recycling technologies should achieve a balance between recycling efficiency,economics and environmental benefits.Finally,this review outlines the opportunities and challenges of recycling key materials for next-generation batteries,and proposes relevant policy recommendations to promote the green and sustainable development of batteries,circular economy,and ecological civilization.
基金supported by the National Natural Science Foundation of China(52374301 and 22279030)the Fundamental Research Funds for the Central Universities(N2223037)+1 种基金Hebei Key Laboratory of Dielectric and Electrolyte Functional Material,Northeastern University at Qinhuangdao(HKDEFM2021201)the Performance subsidy fund for the Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province(22567627H)。
文摘The interface mechanism between catalyst and carbon substrate has been the focus of research.In this paper,the FeCo alloy embedded N,S co-doped carbon substrate bifunctional catalyst(FeCo/S-NC)is obtained by a simple one-step pyrolysis strategy.The experimental results and density functional theory(DFT)calculation show that the formation of FeCo alloy is conducive to promoting electron transfer,and the introduction of S atom can enhance the interaction between FeCo alloy and carbon substrate,thus inhibiting the migration and agglomeration of particles on the surface of carbon material.The FeCo/SNC catalysts show outstanding performance for oxygen reduction reaction(ORR)and oxygen evolution reaction(OER).FeCo/S-NC shows a high half-wave potential(E_(1/2)=0.8823 V)for ORR and a low overpotential at 10 mA cm^(-2)(E_(j=10)=299 mV)for OER.In addition,compared with Pt/C+RuO_(2) assembled Zn-air battery(ZAB),the FeCo/S-NC assembled ZAB exhibits a larger power density(198.8 mW cm^(-2)),a higher specific capacity(786.1 mA h g_(zn)~(-1)),and ultra-stable cycle performance.These results confirm that the optimized composition and the interfacial interaction between catalyst and carbon substrate synergistically enhance the electrochemical performance.
基金financially supported by the National Key R&D Program of China(No.2022YFB3705300)the National Natural Science Foundation of China(Nos.U1960204 and 51974199)the Postdoctoral Fellowship Program of CPSF(No.GZB20230515)。
文摘The infamous type Ⅳ failure within the fine-grained heat-affected zone (FGHAZ) in G115 steel weldments seriously threatens the safe operation of ultra-supercritical (USC) power plants.In this work,the traditional thermo-mechanical treatment was modified via the replacement of hot-rolling with cold rolling,i.e.,normalizing,cold rolling,and tempering (NCT),which was developed to improve the creep strength of the FGHAZ in G115 steel weldments.The NCT treatment effectively promoted the dissolution of preformed M_(23)C_(6)particles and relieved the boundary segregation of C and Cr during welding thermal cycling,which accelerated the dispersed reprecipitation of M_(23)C_(6) particles within the fresh reaustenitized grains during post-weld heat treatment.In addition,the precipitation of Cu-rich phases and MX particles was promoted evidently due to the deformation-induced dislocations.As a result,the interacting actions between precipitates,dislocations,and boundaries during creep were reinforced considerably.Following this strategy,the creep rupture life of the FGHAZ in G115 steel weldments can be prolonged by 18.6%,which can further push the application of G115 steel in USC power plants.
基金financially supported by the National Natural Science Foundation of China(No.52071073,52177208,and52171202)Hebei Province“333 talent project”(No.C20221012)+1 种基金the Science and Technology Project of Hebei Education Department(BJK2023005)Hebei Province Graduate Innovation Funding Program CXZZBS2024177。
文摘03-type layered metal oxides hold great promise for sodium-ion batteries cathodes owing to their energy density advantage.However,the severe irreversible phase transition and sluggish Na^(+)diffusion kinetics pose significant challenges to achieve high-performance layered cathodes.Herein,a boron-doped03-type high entropy oxide Na(Fe_(0.2)Co_(0.15)Cu_(0.05)Ni_(0.2)Mn_(0.2)Ti_(0.2))B_(0.02)O_(2)(NFCCNMT-B_(0.02))is designed and the covalent B-O bonds with high entropy configuration ensure a robust layered structure.The obtained cathode NFCCNMT-B_(0.02)exhibits impressive cycling performance(capacity retention of 95%and 82%after100 cycles and 300 cycles at 1 and 10 C,respectively)and outstanding rate capability(capacity of 83 mAh g^(-1)at 10 C).Furthermore,the NFCCNMT-B_(0.02)demonstrates a superior wide-temperature performance,maintaining the same capacity level(113,4 mAh g^(-1)@-20℃,121 mAh g^(-1)@25℃,and 119 mAh g^(-1)@60℃)and superior cycle stability(90%capacity retention after 100 cycles at 1 C at-20℃).The high-entropy configuration design with boron doping strategy contributes to the excellent sodium-ion storage performance.The high-entropy configuration design effectively suppresses irreversible phase transitions accompanied by small volume changes(ΔV=0.65 A3).B ions doping expands the Na layer distance and enlarges the P3 phase region,thereby enhancing Na^(+)diffusion kinetics.This work offers valuable insights into design of high-performance layered cathodes for sodium-ion batteries operating across a wide temperature.
基金support provided by the National Natural Science Foundation of China(Grant Nos.51972048,U23A20605)support provided by the Performance subsidy fund for Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province(Grant No.22567627H)the additional data in the revised manuscriptsupported by the National Key Research and Development Program of China(No.2022YFB3706300).
文摘High-entropy materials(HEMs),which are newly manufactured compounds that contain five or more metal cations,can be a platform with desired properties,including improved electrocatalytic performance owing to the inherent complexity.Here,a strain engineering methodology is proposed to design transition-metal-based HEM by Li manipulation(LiTM)with tunable lattice strain,thus tailoring the electronic structure and boosting electrocatalytic performance.As confirmed by the experiments and calculation results,tensile strain in the LiTM after Li manipulation can optimize the d-band center and increase the electrical conductivity.Accordingly,the asprepared LiTM-25 demonstrates optimized oxygen evolution reaction and hydrogen evolution reaction activity in alkaline saline water,requiring ultralow overpotentials of 265 and 42 mV at 10 mA cm−2,respectively.More strikingly,LiTM-25 retains 94.6%activity after 80 h of a durability test when assembled as an anion-exchange membrane water electrolyzer.Finally,in order to show the general efficacy of strain engineering,we incorporate Li into electrocatalysts with higher entropies as well.
基金financially National Natural Science Foundation of China (NSFC) (52274295)Natural Science Foundation of Hebei Province (E2021501029, E2020501001, A2021501007, E2022501028, E2022501029)+11 种基金Natural Science Foundation - Steel and Iron Foundation of Hebei Province (No. E2022501030)Fundamental Research Funds for the Central Universities (No. N2323025, N2323013, N2302016, N2223009, N2223010, N2123035, N2023040)Performance subsidy fund for Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province (22567627H)Science and Technology Project of Hebei Education Department (ZD2022158)2023 Hebei Provincial doctoral candidate Innovation Ability training funding project (CXZZBS2023163)2023 Hebei Provincial Postgraduate Student Innovation Ability training funding project (CXZZSS2023195)Central Guided Local Science and Technology Development Fund Project of Hebei province (226Z4401G)The Fundamental Research Funds for the Central Universities (N2423052)Hebei Provincial Doctoral Candidate Innovation Ability Training Funding Project(CXZZBS2024176)The Science and Technology Project of Qinhuangdao City (202302B006)Science and Technology Project of Hebei Education Department (ZD2022158 and QN2024238)The Basic Research Project of Shijiazhuang City。
文摘Rechargeable metal-ion batteries, such as lithium-ion batteries(LIBs) and sodium-ion batteries(SIBs),have raised more attention because of the large demand for energy storage solutions. Undoubtedly, electrode materials and electrolytes are key parts of batteries, exhibiting critical influence on the reversible capacity and span life of the metal-ion battery. Nonetheless, researchers commonly express concerns regarding the stability of both electrodes and electrolytes. Given its commendable stability attributes,high-entropy materials have garnered widespread acclaim and have been applied in many fields since their inception, notably in energy storage. However, while certain high-entropy designs have achieved substantial breakthroughs, some have failed to meet anticipated outcomes within the high energy density energy storage materials. Moreover, there is a lack of comprehensive summary research on the corresponding mechanisms and design principles of high-entropy designs. This review examines the current high-entropy designs for cathodes, anodes, and electrolytes, aiming to summarize the design principle,potential mechanisms, and electrochemical performance. We focus on their structural characteristics,interface characteristics, and prospective development trends. At last, we provide a fair evaluation along-side succinct development suggestions.
基金financially supported by the National Natural Science Foundation of China (Nos.52171202,52177208,52071073)the financial support from CSIRO+3 种基金the Department of Climate Change,Energy,the Environment and Water (DCCEEW)Australian Governmentthe Australian Hydrogen Research Network (AHRN)the Australian Research Council (DE230100327 and LP220200583)the support from the DCCEEW International Clean Innovation Researcher Networks Grant (ICIRN000011)。
文摘Metal(Li,Na,K,Al)-ion batteries and lithium-sulfur and lithium-tellurium batteries are gaining recognition for their eco-friendly characteristics,substantial energy density,and sustainable attributes.However,the overall performance of rechargeable batteries heavily depends on their electrode materials.Transition metal tellurides have recently gained significant attention due to their high electrical conductivity and density.Cobalt telluride has received the most extensive research due to its catalytic activity,unique magnetic properties,and diverse composition and crystal structure.Nevertheless,its limited conductivity and significant volume variation contribute to electrode structural deterioration and rapid capacity decline.This review comprehensively summarizes recent advances in rational design and synthesis of modified cobalt telluride-based electrodes,encompassing defect engineering(Te vacancies,cation vacancies,heterointerfaces,and homogeneous interfaces)and composite engineering(derived carbon from precursors,carbon fibers,Mxene,graphene nanosheets,etc.).Particularly,the intricate evolution mechanisms of the conversion reaction process during cycling are elucidated.Furthermore,these modified strategies applied to other transitional metal tellurides,such as iron telluride,nickel telluride,zinc telluride,copper telluride,molybdenum telluride,etc.,are also thoroughly summarized.Additionally,their application extends to emerging aqueous zinc-ion batteries.Finally,potential challenges and prospects are discussed to further propel the development of transition metal tellurides electrode materials for next-generation rechargeable batteries.
基金The work was supported by Humanities and Social Sciences Fund of the Ministry of Education(No.22YJA630119)the National Natural Science Foundation of China(No.71971051)Natural Science Foundation of Hebei Province(No.G2021501004).
文摘With the development of big data and social computing,large-scale group decisionmaking(LGDM)is nowmerging with social networks.Using social network analysis(SNA),this study proposes an LGDM consensus model that considers the trust relationship among decisionmakers(DMs).In the process of consensusmeasurement:the social network is constructed according to the social relationship among DMs,and the Louvain method is introduced to classify social networks to form subgroups.In this study,the weights of each decision maker and each subgroup are computed by comprehensive network weights and trust weights.In the process of consensus improvement:A feedback mechanism with four identification and two direction rules is designed to guide the consensus of the improvement process.Based on the trust relationship among DMs,the preferences are modified,and the corresponding social network is updated to accelerate the consensus.Compared with the previous research,the proposedmodel not only allows the subgroups to be reconstructed and updated during the adjustment process,but also improves the accuracy of the adjustment by the feedbackmechanism.Finally,an example analysis is conducted to verify the effectiveness and flexibility of the proposed method.Moreover,compared with previous studies,the superiority of the proposed method in solving the LGDM problem is highlighted.
基金supported by the National Natural Science Foundation of China(Nos.52201203 and 52171107)the Hebei Provincial Natural Science Foundation,China(No.E2021501026)+1 种基金the National Natural Science Foundation of China-Joint Fund of Iron and Steel Research(No.U1960204)the“333”Talent Project of Hebei Province,China(No.B20221001).
文摘Inconel 718 is the most popular nickel-based superalloy and is extensively used in aerospace,automotive,and energy indus-tries owing to its extraordinary thermomechanical properties.The effects of different two-step solid solution treatments on microstructure andδphase precipitation of Inconel 718 alloy were studied,and the transformation mechanism fromγ″metastable phase toδphase was clarified.The precipitates were statistically analyzed by X-ray diffractometry.The results show that theδphase content firstly increased,and then decreased with the temperature of the second-step solid solution.The changes in microstructure andδphase were studied by scanning electron microscopy and transmission electron microscopy.An intragranularδphase formed in Inconel 718 alloy at the second-[100]_(δ)[011]γ step solid solution temperature of 925℃,and its orientation relationship withγmatrix was determined as//and(010)_(δ)//(111)γ.Furthermore,the Vickers hardness of different heat treatment samples was measured,and the sample treated by second-step solid solution at 1010℃ reached the maximum hardness of HV 446.84.
基金Supported by the Natural Science Foundation of Hebei(D2024501002)Fundamental Research Funds for the Central Universities(N2423020)Major Science and Technology Projects of CNPC(2021ZZ10)。
文摘Based on the observation and analysis of cores and thin sections,and combined with cathodoluminescence,laser Raman,fluid inclusions,and in-situ LA-ICP-MS U-Pb dating,the genetic mechanism and petroleum geological significance of calcite veins in shales of the Cretaceous Qingshankou Formation in the Songliao Basin were investigated.Macroscopically,the calcite veins are bedding parallel,and show lenticular,S-shaped,cone-in-cone and pinnate structures.Microscopically,they can be divided into syntaxial blocky or columnar calcite veins and antitaxial fibrous calcite veins.The aqueous fluid inclusions in blocky calcite veins have a homogenization temperature of 132.5–145.1℃,the in-situ U-Pb dating age of blocky calcite veins is(69.9±5.2)Ma,suggesting that the middle maturity period of source rocks and the conventional oil formation period in the Qingshankou Formation are the sedimentary period of Mingshui Formation in Late Cretaceous.The aqueous fluid inclusions in fibrous calcite veins with the homogenization temperature of 141.2–157.4℃,yields the U-Pb age of(44.7±6.9)Ma,indicating that the middle-high maturity period of source rocks and the Gulong shale oil formation period in the Qingshankou Formation are the sedimentary period of Paleocene Yi'an Formaiton.The syntaxial blocky or columnar calcite veins were formed sensitively to the diagenetic evolution and hydrocarbon generation,mainly in three stages(fracture opening,vein-forming fluid filling,and vein growth).Tectonic extrusion activities and fluid overpressure are induction factors for the formation of fractures,and vein-forming fluid flows mainly as diffusion in a short distance.These veins generally follow a competitive growth mode.The antitaxial fibrous calcite veins were formed under the driving of the force of crystallization in a non-competitive growth environment.It is considered that the calcite veins in organic-rich shale of the Qingshankou Formation in the study area has important implications for local tectonic activities,fluid overpressure,hydrocarbon generation and expulsion,and diagenesis-hydrocarbon accumulation dating of the Songliao Basin.
基金Supported by the Program for Qinhuangdao Self-financing Science and Technology Plan of 2008 (No.201805A143).
文摘AIM:To analyze the distribution of fibrovascular proliferative membranes(FVPMs)in proliferative diabetic retinopathy(PDR)patients that treated with pars plana vitrectomy(PPV),and to evaluate the outcomes separately.METHODS:This was a retrospective and cross-sectional study.Consecutive 25-gauge(25-G)PPV cases operated for PDR from May 2018 to April 2020.According to the FVPMs images outlined after operations,subjects were assigned into three groups:arcade type group,juxtapapillary type group,and central type group.All patients were followed up for over one year.General characteristics,operation-related variables,postoperative parameters and complications were recorded.RESULTS:Among 103 eyes recruited,the FVPMs distribution of nasotemporal and inferiosuperioral was significantly different(both P<0.01),with 95(92.23%)FVPMs located in the nasal quadrants,and 74(71.84%)in the inferior.The eyes with a central FVPM required the longest operation time,with silicon oil used in most patients,generally combined with tractional retinal detachment(RD)and rhegmatogenous RD,the worst postoperative bestcorrected visual acuity(BCVA)and the highest rates of recurrent RD(all P<0.05).FVPM type,age of onset diabetes mellitus,preoperative BCVA,and combined with tractional RD and rhegmatogenous RD were significantly associated with BCVA improvement(all P<0.05).Compared with the central type group,the arcade type group had higher rates of BCVA improvement.CONCLUSION:FVPMs are more commonly found in the nasal and inferior mid-peripheral retina in addition to the area of arcade vessels.Performing 25-G PPV for treating PDR eyes with central FVPM have relatively worse prognosis.
基金financially supported by the National Natural Science Foundation of China (nos. 51774002 and 51672156)Anhui Provincial Science Fund for Excellent Young Scholars (no. gxyqZD2016066)+2 种基金the National Key Basic Research Program of China (2014CB932400)Guangdong special support program (2015TQ01N401)Shenzhen Technical Plan Project (KQJSCX20160226191136)
文摘Supercapacitors known as typical electrochemical capacitors have been considered as one of the most promising candidates of energy storage systems owing to their advantages such as high-power density,long life span and lower production cost.The electrode materials play a crucial role on properties of supercapacitors.Hence,many researches have been focused on the development of novel electrode materials for high-performance supercapacitors.NiCo_2O_4as supercapacitor electrode material has drawn more and more attentions in recent years due to its outstanding advantages,such as high theoretical capacity,low cost,natural abundance and easy of synthesis.However,the NiCo_2O_4always suffer from severe capacity deterioration because of the low electrical conductivity and small surface area.Hence,it is necessary to systematically and comprehensively summarize the progress in understanding and modifying NiCo_2O_4-based materials from various aspects.In this review,the structure and synthesis method of NiCo_2O_4-based materials are discussed in detail.And then,the major goal of this review is to highlight new progress in using proposed strategies to improve the cycling stability and rate capacity of NiCo_2O_4-based materials,including synthesis,control of special morphologies and design of composite materials.Finally,an insight into the future research and development of Ni Co_2O_4-based materials for supercapacitors is prospected.
基金Project(2014CB643405) supported by the National Basic Research Program of ChinaProjects(51204036,51234009) supported by the National Natural Science Foundation of ChinaProject(BJ201604) supported by the Program for Top Young Talents of Higher Education Institutions of Hebei Province,China
文摘The mineralogical phase transformation of a low-grade nickel laterite ore during pre-roasting process and the extraction of silicon during alkaline leaching process were investigated.The results indicate that the reaction activity of nickel ores is effectively improved by pre-roasting at650°C for2h,because of the transformation of lizardite into magnesium olivine and protoenstatite.When finely ground ore samples(44-61μm)pre-roasted firstly react with sodium hydroxide solution(60g/L)with a solid/liquid ratio of1:5at140°C for120min,the extraction of silicon can reach89.89%,and the other valuable elements of magnesium,iron and nickel are accumulated in the solid residues.The leaching kinetics of nickel laterite ore can be described successfully by the diffusion through the product layer control model.The activation energy is calculated to be11.63kJ/mol and the kinetics equation can be expressed as1-3(1-x)2/3+2(1-x)=13.53×10-2exp[-11.63/(RT)]t.
基金supported in part by the National Natural Science Foundation of China(61573077,U1808205)the National Key Research and Development Program of China(2017YFA0700300)
文摘In this paper,we investigate formation tracking control of autonomous underwater vehicles(AUVs)with model parameter uncertainties and external disturbances.The external disturbances due to the wind,waves,and ocean currents are combined with the model parameter uncertainties as a compound disturbance.Then a disturbance observer(DO)is introduced to estimate the compound disturbance,which can be achieved within a finite time independent of the initial estimation error.Based on a DO,a novel fixed-time sliding control scheme is developed,by which the follower vehicle can track the leader vehicle with all the states globally stabilized within a given settling time.The effectiveness and performance of the method are demonstrated by numerical simulations.
基金Project(51204054)supported by the National Natural Science Foundation of ChinaProject(2007CB613603)supported by the National Basic Research Program of ChinaProject(N140204011)supported by the Ministry of Education Basic Scientific Research Business Expenses,China
文摘A novel process was proposed for the utilization of potash feldspar by roasting in the presence of sodium carbonate. The effects of roasting temperature, granularity, molar ratio of sodium carbonate to potash feldspar and roasting time on the silica extraction rate were investigated. Under the optimal roasting conditions, the silica extraction rate was 98%. The optimal conditions, determined using an orthogonal experiment, were found to be roasting temperature of 875 A degrees C, potash feldspar granularity of 74-89 mu m, molar ratio of sodium carbonate to potash feldspar of 1.2:1, and roasting time of 80 min. The kinetics of potash feldspar roasting in the presence of sodium carbonate was described by the shrinking core model and the reaction rate was found to be controlled by the chemical reaction at the particle surface. According to the Arrhenius expression, the activation energy was 164.99 kJ/mol, and the process could be expressed as [1-(1-alpha)(1/3)]=2.66x10(5) exp[-164990/(RT)] t.
基金financially supported by the National Natural Science Foundation of China(Nos.51871046,51902046,52071073,51874079,51571054,51771046,and 51674068)the Natural Science Foundation of Liaoning Province,China(No.201602257)+2 种基金Natural Science Foundation of Hebei Province,China(Nos.E2019501097,E2018501091,E2020501004)the Science and Technology Project of Hebei Province,China(No.15271302D)the Fundamental Research Funds for the Central Universities,China(Nos.N182304017,N182304015,N172302001,N172304044).
文摘Ultrafine nano-scale Cu2Sb alloy confined in a three-dimensional porous carbon was synthesized using NaCl template-assisted vacuum freeze-drying followed by high-temperature sintering and was evaluated as an anode for sodium-ion batteries(SIBs)and potassium-ion batteries(PIBs).The alloy exerts excellent cycling durability(the capacity can be maintained at 328.3 mA·h·g^(-1) after 100 cycles for SIBs and 260 mA·h·g^(-1) for PIBs)and rate capability(199 mA·h·g^(-1) at 5 A·g^(-1) for SIBs and 148 mA·h·g^(-1) at 5 A·g^(-1) for PIBs)because of the smooth electron transport path,fast Na/K ion diffusion rate,and restricted volume changes from the synergistic effect of three-dimensional porous carbon networks and the ultrafine bimetallic nanoalloy.This study provides an ingenious design route and a simple preparation method toward exploring a high-property electrode for K-ion and Na-ion batteries,and it also introduces broad application prospects for other electrochemical applications.
基金supported by the National Natural Science Foundation of China(U1960107)the Natural Science Foundation of Hebei Province(E2022501014)+3 种基金the “333”Talent Project of Hebei Province(A202005018)the Fundamental Research Funds for the Central Universities(N2123034)the Science and Technology Research Youth Fund Project of Higher Education Institutions of Hebei Province(QN2022196)the Performance subsidy fund for Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province(22567627H)。
文摘Fe-Mn based layer oxides cathode materials have attracted widespread attention as a potential candidate for sodium-ion batteries(SIBs)owing to the earth abundance,cost-effectiveness and acceptable specific capacity.However,the irreversible phase transition often brings rapid capacity decay,which seriously hinders the practical application in large-scale energy storage.Herein,we design a nickel-doped Na_(0.70)Fe_(0.10)Cu_(0.20)Ni_(0.05)Mn_(0.65)O_(2)(NFCNM-0.05)cathode material of SIBs with activated anionic redox reaction,and then inhibit the harmful phase transition.The ex-situ X-ray diffraction patterns demonstrate the NFCNM-0.05 always keeps the P2 phase during the sodiation/desodiation process,indicating a high structure stability.The ex-situ X-ray photoelectron spectroscopy implies the redox reactions between O2-and O-occur in the charging process,which offers extra specific capacity.Thus,the NFCNM-0.05 electrode delivers a high initial discharge capacity of 148 mA h g-1and remains a prominent cycling stability with an excellent capacity retention of 95.9%after 200 cycles at 1 C.In addition,the electrochemical impedance spectroscopy and galvanostatic intermittent titration technique show the NFCNM-0.05 electrode possesses fast ion diffusion ability,which is beneficial for the enhancement of rate performance.Even at 10 C,the NFCNM-0.05 can offer a reversible discharge capacity of 81 mA h g-1.DFT calculation demonstrates the doping of appropriate amount of Ni ions is benefit for the enhancement of the electrochemical performance of the layer oxides.This work provides an effective strategy to enhance the electrochemical performance of Fe-Mn based cathode materials of SIBs.
基金supported by the National Natural Science Foundation of China(U1960107)the“333”Talent Project of Hebei Province(A202005018)+1 种基金the Fundamental Research Funds for the Central Universities(N2123034 and N2123001)Hebei Key Laboratory of Dielectric and Electrolyte Functional Material,Northeastern University at Qinhuangdao(HKDEFM2021201)。
文摘Li_(5)Cr_(7)Ti_(6)O_(25) is regarded as a promising anode material for Li-ion batteries(LIBs)because of its low cost and high theoretical capacity.However,the inherently poor conductivity significantly limits the enhancement of its rate capability and cycling stability,especially at high current densities.In this work,we construct one-dimensional Li_(5)Cr_(7)Ti_(6)O_(25)/C nanofibers by electrospinning method to enhance the kinetic,which realizes high cycling stability.Carbon coating enhances the structure stability,insertion/extraction reversibility of Li-ions and electrochemical reaction activity,and facilitates the transfer of Li-ions.Benefited from the unique architecture and component,the Li_(5)Cr_(7)Ti_(6)O_(25)/C(6.6 wt%)nanofiber shows an excellent rate capability with a reversible de-lithiation capacity of 370.8,290.6,269.2,254.3 and 244.9 m Ah g^(-1) at 200,300,500,800 and 1000 m A g^(-1),respectively.Even at a higher current density of 1 A g^(-1),Li_(5)Cr_(7)Ti_(6)O_(25)/C(6.6 wt%)nanofiber shows high cycling stability with an initial de-lithiation capacity of 237.8 m Ah g^(-1) and a capacity retention rate of about 84%after 500 cycles.The density functional theory calculation result confirms that the introduction of carbon on the surface of Li_(5)Cr_(7)Ti_(6)O_(25) changes the total density of states of Li_(5)Cr_(7)Ti_(6)O_(25),and thus improves electronic conductivity of the composite,resulting in a good electrochemical performance of Li_(5)Cr_(7)Ti_(6)O_(25)/C nanofibers.Li_(5)Cr_(7)Ti_(6)O_(25)/C nanofibers indicate a great potential as an anode material for the next generation of high-performance LIBs.
基金supported by the Natural Science Foundation of Hebei Province,China (No.E2014501077)Natural Science Foundation of China (No.51275345)
文摘To investigate cutting performance in the helical milling of carbon fiber reinforced polymer(CFRP),experiments were conducted with unidirectional laminates.The results show that the influence of cutting parameters is very significant in the helical milling process. The axial force increases with the increase of cutting speed, which is below 95 m/min; otherwise, the axial force decreases with the increase of cutting speed. The resultant force always increases when cutting speed increases; with the increase of tangential and axial feed rates, cutting forces increase gradually. In addition, damage rings can appear in certain regions of the entry edges; therefore, the relationship between machining performance(cutting forces and holemaking quality) and cutting parameters is established using the nonlinear fitting methodology. Thus, three cutting parameters in the helical milling of CFRP, under the steady state, are optimized based on the multi-objective genetic algorithm, including material removal rate and machining performance. Finally, experiments were carried out to prove the validity of optimized cutting parameters.
基金Project(2007CB613603)supported by the National Basic Research Program of China
文摘A novel process was proposed for recovering nickel from nickeliferous laterite ores.First of all,silicon and magnesium were removed from lateritic ore by high concentration sodium hydroxide leaching and carbonation respectively,so as to enrich nickel. Then the method of ammonia carbonate leaching was adopted to recover nickel from the carbonized slag,and the remaining residue was used as a raw material for recovering iron.The effects of temperature,ammonia carbonate concentration,liquid/solid ratio and stirring speed on the recovery of nickel were examined.When the leached residue reacted with ammonia carbonate(6 mol·L- 1)in a ratio of liquid-to-solid of 5-1 at 60℃for 150 min at the stirring speed of 300 r·min- 1,approximate more than 95%nickel was recovered.During the whole process,there was no contamination produced and the chemical raw materials were recycled,thus the process was a green technology that having good social benefit.