With the approaching of large-scale retirement of power lithium-ion batteries(LIBs),their urgent handling is required for environmental protection and resource ***,at present,substantial spent power batteries,especial...
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With the approaching of large-scale retirement of power lithium-ion batteries(LIBs),their urgent handling is required for environmental protection and resource ***,at present,substantial spent power batteries,especially for those high recovery value cathode materials,have not been greenly,sustainably,and efficiently *** to the traditional recovery method for cathode materials with high energy consumption and severe secondary pollution,the direct repair regeneration,as a new type of short-process and efficient treatment methods,has attracted widespread ***,it still faces challenges in homogenization repair,electrochemical performance decline,and scaling-up *** promote the direct regeneration technology development of failed NCM materials,herein we deeply discuss the failure mechanism of nickel-cobalt-manganese(NCM)ternary cathode materials,including element loss,Li/Ni mixing,phase transformation,structural defects,oxygen release,and surface degradation and *** on this,the detailed analysis and summary of the direct regeneration method embracing solid-phase sintering,eutectic salt assistance,solvothermal synthesis,sol-gel process,spray drying,and redox mediation are ***,the upcycling strategy for regeneration materials,such as single-crystallization and high-nickelization,structural regulation,ion doping,and surface engineering,are discussed in ***,the challenges faced by the direct regeneration and corresponding countermeasures are pointed ***,this review provides valuable guidance for the efficient and high-value recovery of failed cathode materials.
In response to the growing demand for energy efficiency, safety, and lightweight designs in new energy vehicles, this study addresses the challenge of balancing strength and toughness in ultra-high strength steel(UHSS...
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In response to the growing demand for energy efficiency, safety, and lightweight designs in new energy vehicles, this study addresses the challenge of balancing strength and toughness in ultra-high strength steel(UHSS) components produced by hot stamping. An innovative hot stamping process based on a martensite-bainite(M-B) complex-phase microstructure was proposed to enhance the strength and toughness of UHSS. The microstructural evolution of the M-B complexphase during the hot stamping process was investigated using commercial B1800HS steel. With a microstructure consisting of 87.4.% martensite, 8.7% lower bainite, and 3.9% film-like retained austenite by volume fraction, the steel achieved a tensile strength of 1944 MPa, total elongation of 9.66%, and impact energy of 25.8 J. Compared with conventional hot stamping, the strength of the material showed only a slight improvement, whereas elongation and impact energy were enhanced by approximately 53% and 32%, respectively. A quantitative relationship among process parameters, resulting microstructure, and mechanical properties was established. Optimization between strength and toughness was observed when the low bainite volume fraction ranged from 5.06% to 8.73%. The toughening mechanisms are attributed to the refinement of martensite lath bundles(width of 202 nm) facilitated by bainite formation, the increase in high-angle grain boundaries, and the presence of nanoscale retained austenite(width of 80 nm) between the laths. Additionally, the refinement of grains and the formation of nanoscale(Nb, Ti)C precipitates(diameter of 17 nm) further contributed to the overall strength. The developed M-B complexphase process, which involves medium-temperature slow cooling followed by rapid low-temperature quenching, provides an optimal combination of strength and toughness for a wide range of applications.
The mechanical and thermodynamic properties of W-Ti alloys(including W_(15)Ti_(1),W_(14)Ti_(2),W_(12)Ti_(4) and W_(8)Ti_(8) alloys)were investigated by the first-principles approach based on density functional *** res...
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The mechanical and thermodynamic properties of W-Ti alloys(including W_(15)Ti_(1),W_(14)Ti_(2),W_(12)Ti_(4) and W_(8)Ti_(8) alloys)were investigated by the first-principles approach based on density functional *** results indicate that W-Ti alloys except W_(8)Ti_(8) are thermodynamically *** modulus and hardness of W-Ti alloys are smaller than those of pure tungsten and gradually decrease with increasing Ti ***,their B/G ratios and Poisson's ratios exceed those of pure tungsten,suggesting that the introduction of Ti decreases the mechanical strength while enhancing the ductility of W-Ti *** thermal expansion coefficients for W-Ti alloys all surpass those of pure tungsten,indicating that the introduction of titanium exacerbates the thermal expansion behavior of W-Ti ***,elevated pressure has the capacity to suppress the thermal expansion tendencies in titanium-doped tungsten *** study offers theoretical insights for the design of nuclear materials by exploring the mechanical and thermodynamic properties of W-Ti alloys.
Laser etching and laser chemical vapor deposition(LCVD)techniques were proposed for the rapid preparation of high-purity,strongly bonded SiC porous micro-nano-coatings on quartz *** laser serves as an external driving...
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Laser etching and laser chemical vapor deposition(LCVD)techniques were proposed for the rapid preparation of high-purity,strongly bonded SiC porous micro-nano-coatings on quartz *** laser serves as an external driving force for the vertical growth of SiC whiskers,facilitating the formation of a porous nanostructure that resembles coral models found in the macroscopic biological *** porous nanostructures are beneficial for reducing thermal expansion mismatch and relieving residual *** is capable of eliminating the cracks on the surface of SiC coatings as well as enhancing the bonding of SiC coatings with quartz substrates to avoid coating detachment.
The generation and manipulation of spin-polarized electrons at room temperature are essential for the development of advanced spin-optoelectronic *** this work,a one-pot method was used to successfully synthesize homo...
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The generation and manipulation of spin-polarized electrons at room temperature are essential for the development of advanced spin-optoelectronic *** this work,a one-pot method was used to successfully synthesize homogenous Mn:CsPbBr_(3) perovskite quantum dots in air with particle sizes of 7−8 *** effects of Mn doping on the structure,optical and magnetic properties of CsPbBr_(3) quantum dots were *** findings demonstrated proper Mn doping improved the crystallinity and photoluminescence(PL)of quantum *** prepared quantum dots have a narrow full width at half maximum emission(FWHM)of about 17−20 *** magnetic properties of the doped samples and the effect of the magnetic field on the PL spectra properties were *** results show that trace Mn doping can improve the room-temperature ferromagnetism of CsPbBr_(3) quantum *** with magnetic elements makes CsPbBr_(3) quantum dots more responsive to the applied magnetic *** at a lower 50 mT magnetic field,the PL peak of Mn:CsPbBr_(3) still declined 5.91%.Mn:CsPbBr_(3) quantum dots are a new type of multifunctional material that is beneficial to spintronics *** work demonstrates a low-cost synthesis *** should make all-inorganic perovskite quantum dots a promising material for room-temperature spin optoelectronic devices.
The exceptional photoelectric performance and high compatibility of perovskite materials render perovskite solar cells highly promising for extensive development,thus garnering significant *** perovskite solar cells,t...
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The exceptional photoelectric performance and high compatibility of perovskite materials render perovskite solar cells highly promising for extensive development,thus garnering significant *** perovskite solar cells,the hole transport layer plays a crucial *** the commonly employed organic small molecule hole transport material Spiro-OMeTAD,a certain period of oxidation treatment is required to achieve complete transport ***,this posttreatment oxidation processes typically rely on ambient oxidation,which poses challenges in terms of precise control and leads to degradation of the perovskite light absorption *** approach fails to meet the demands for high efficiency and stability in practical ***,the mechanism of ultrafast laser on Spiro-OMeTAD and the reaction process for laser-induced oxidation of it are ***2at Perovskite/Spiro-OMeTAD interface breaks down to produce I2upon ultrafast laser irradiation and I2promote the oxidation *** the laser irradiation oxidation processing,a higher stability of perovskite solar cells is *** work establishes a new approach toward oxidation treatment of Spiro-OMeTAD.
The O3-type layered cathode with high Ni content has attracted much attention because of its high capacity and simple synthesis ***,surface side reaction and O3-P3 phase transitions would occur during Na+insertion/ext...
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The O3-type layered cathode with high Ni content has attracted much attention because of its high capacity and simple synthesis ***,surface side reaction and O3-P3 phase transitions would occur during Na+insertion/extraction,resulting in unsatisfying electrochemical ***,O3-Na[Ni_(0.6)Co_(0.2)Mn_(0.2)]O_(2)(NNCM622)cathode is modified by a NaTiOx coating layer in a wet chemistry method,which reduces the parasitic reaction and facilitates Na+***,the partially doped Ti improves structural stability by restraining the irreversible multiple-phase *** a result,the modified NNCM622 cathode obtains a high specific capacity of 143.4 mAh g^(−1)and an improved capacity retention of 69%after 300 *** work offers new prospects for stabilizing the NNCM622 cathode with a feasible coating strategy.
A numerical method to predict the bursting strength of filament wound composite rocket motor case is proposed *** method can evaluate the longitudinal stress evolution of each composite layer as impregnated filaments ...
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A numerical method to predict the bursting strength of filament wound composite rocket motor case is proposed *** method can evaluate the longitudinal stress evolution of each composite layer as impregnated filaments with fiber tension are wound layer by layer,and consider the effects of accumulated stress and deformation during filament winding on the bursting strength of composite ***∅520 mm composite cases as a case study,the filament-winding-process-induced stress and deformation as well as progressive damage behavior are numerically predicted,followed by a comparison with experimental *** numerical results show that the predicted bursting pressures for composite cases manufactured on the mandrels with and without a flexible component are 14.20 MPa and 21.40 MPa,*** values exhibit slight deviation from the measured pressures of 13.50 MPa and 21.57 ***,the predicted damage locations,situated respectively in the dome and cylinder,agree well with the experimental *** observations indicate that use of flexible component reduces the load-bearing capacity of the ***,it validates the reliability and accuracy of the proposed numerical method in predicting the bursting strength of composite cases.
Micro/nanorobots(MNRs)are envisioned to provide revolutionary changes to therapies for infectious diseases as they can deliver various antibacterial agents or energies to many hard-to-reach infection ***,existing MNRs...
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Micro/nanorobots(MNRs)are envisioned to provide revolutionary changes to therapies for infectious diseases as they can deliver various antibacterial agents or energies to many hard-to-reach infection ***,existing MNRs face substantial challenges in addressing complex infections that progress from superficial to deep ***,we develop swarming magnetic Fe3O4@polydopamine-tannic acid nanorobots(Fe3O4@PDA-TA NRs)capable of performing targeted bacteria elimination in complicated bacterial infections by integrating superficial photothermal and deep chemical *** Fe3O4@PDA-TA nanoparticles(NPs),serving as building blocks of the nanorobots,are fabricated by in situ polymerization of dopamine followed by TA *** driven by alternating magnetic fields,Fe3O4@PDA-TA NPs can assemble into large energetic microswarms continuously flowing forward with tunable ***,the swarming Fe3O4@PDA-TA NRs can be navigated to achieve rapid broad coverage of a targeted superficial area from a distance and rapidly eradicate bacteria residing there upon exposure to near-infrared(NIR)light due to their efficient photothermal ***,they can concentrate at deep infection sites by traversing through confined,narrow,and tortuous passages,exerting sustained antibacterial action through their surface TA-induced easy cell adhesion and subsequent membrane ***,the swarming Fe3O4@PDA-TA NRs show great potential for addressing complex superficial-to-deep *** study may inspire the development of future therapeutic microsystems for various diseases with multifunction synergies,task flexibility,and high efficiency.
Nickel selenides have been studied as potential anode materials for sodium-ion batteries due to their high theoretical ***,the low electrical conductivity and the large volumetric variation during the charging/dischar...
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Nickel selenides have been studied as potential anode materials for sodium-ion batteries due to their high theoretical ***,the low electrical conductivity and the large volumetric variation during the charging/discharging process greatly reduce the specific capacity and cycling lifespan of the *** this paper,a simple strategy to fabricate NiSe nanoparticles enclosed in carbon hollow nanofibers(NiSe/C@CNF)is proposed,involving the preparation of Ni-precursor nanofibers by electrospinning,the coating of polydopamine and the formation of NiSe/C@CNF by calcination and *** combination of NiSe nanoparticles and porous carbon hollow nanofibers creates a strong conductive environment,which enhances the dynamic ability of sodium-ion transport and improves charge storage *** fabricated NiSe/C@CNF material exhibits excellent *** demonstrates a high rate capability,with specific capacities of 406.8 and 300.1 mAh·g^(-1)at 0.1 and 5.0 A·g^(-1),*** results highlight the potential of NiSe/C@CNF as an anode material for sodium-ion batteries,offering a large capacity and long life.
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