The overuse and ineffective management of plastics have led to significant environmental pollution. Catalytic upcycling into value-added chemicals has emerged as a promising solution. This review provides a comprehens...
详细信息
The overuse and ineffective management of plastics have led to significant environmental pollution. Catalytic upcycling into value-added chemicals has emerged as a promising solution. This review provides a comprehensive overview of recent advances in catalytic upcycling, focusing on the cleavage of chemical bonds such as carbon-carbon (C-C), carbon-oxygen (C-O), and carbon-hydrogen (C-H) in plastics. It systematically discusses plastics conversion via electrocatalysis, thermal catalysis, and photocatalysis. Additionally, it explores the conversion of plastics into value-added chemicals and functional polymers. The review also addresses the challenges in this field and aims to offer insights for developing sustainable and effective plastics upcycling technologies.
Deep learning has achieved great progress in image recognition,segmentation,semantic recognition and game *** this study,a latest deep learning model,a conditional diffusion model was adopted as a surrogate model to p...
详细信息
Deep learning has achieved great progress in image recognition,segmentation,semantic recognition and game *** this study,a latest deep learning model,a conditional diffusion model was adopted as a surrogate model to predict the heat transfer during the casting process instead of numerical *** conditional diffusion model was established and trained with the geometry shapes,initial temperature fields and temperature fields at t_(i) as the condition and random noise sampled from standard normal distribution as the *** output was the temperature field at t_(i+1).Therefore,the temperature field at t_(i+1)can be predicted as the temperature field at t_(i) is known,and the continuous temperature fields of all the time steps can be predicted based on the initial temperature field of an arbitrary 2D geometry.A training set with 3022D shapes and their simulated temperature fields at different time steps was *** accuracy for the temperature field for a single time step reaches 97.7%,and that for continuous time steps reaches 69.1%with the main error actually existing in the sand *** effect of geometry shape and initial temperature field on the prediction accuracy was investigated,the former achieves better result than the latter because the former can identify casting,mold and chill by different colors in the input *** diffusion model has proved the potential as a surrogate model for numerical simulation of the casting process.
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...
详细信息
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.
We are delighted to introduce this Special Issue of Acta Metallurgica Sinica(English Letters)dedicated to"Thermoelectric materials and Devices."Thermoelectric materials and devices have emerged as a promisin...
详细信息
We are delighted to introduce this Special Issue of Acta Metallurgica Sinica(English Letters)dedicated to"Thermoelectric materials and Devices."Thermoelectric materials and devices have emerged as a promising technology for sustainable energy solutions,enabling efficient conversion between heat and *** special collection highlights the latest advancements in the field,showcasing cutting-edge research and fostering interdisciplinary collaboration among researchers worldwide.
Graphene prepared by non-covalent modification of sulfonated poly(ether-ether-ketone)(SPG)was combined with polyvinylidene fluoride(PVDF)/Al to improve the PVDF/Al thermal conductivity while reducing the effect of the...
详细信息
Graphene prepared by non-covalent modification of sulfonated poly(ether-ether-ketone)(SPG)was combined with polyvinylidene fluoride(PVDF)/Al to improve the PVDF/Al thermal conductivity while reducing the effect of the thermal resistance at the graphene-polymer *** regulation rule of SPG with different contents on the energy release of fluorine-containing system was *** the content of SPG is 4%,the peak pressure and rise rate of SPG/PVDF/Al composite powder during ignition reach the maximum of 4845.28 kPa and 8683.58 kPa/*** the content of SPG is 5%,the PVDF/Al composite powder is completely coated by SPG,and the calorific value of the material reachs the maximum of 29.094 kJ/*** the design and micro-control of the composite powder,the calorific value of the material can be effectively improved,but the improvement of the mass release rate still depends on the graphene content and surface modification state.
Ag vacancies have been shown to regulate the thermoelectric properties of Ag_(2)***,their effect on the mechanical properties of Ag_(2)S remains *** this study,Ag_(2)S-based samples with various Ag vacancy concentrati...
详细信息
Ag vacancies have been shown to regulate the thermoelectric properties of Ag_(2)***,their effect on the mechanical properties of Ag_(2)S remains *** this study,Ag_(2)S-based samples with various Ag vacancy concentration were prepared,and their mechanical properties were investigated experimentally and *** the bending strength and fracture strain decrease with increasing Ag vacancy ***,the dimple size on the fracture surfaces of the samples gradually reduces with increasing Ag vacancy concentration,further confirming the reduction in material *** functional theory results reveal that Ag vacancies lead to the disruption of Ag–S bonds in Ag_(2)S at low ultimate strains,consequently causing a simultaneous reduction in both strength and deformability,which agrees reasonably well with the experimental *** work provides new insights into the effect of vacancies on the mechanical properties of Ag_(2)S materials,which could guide the design of fast ionic thermoelectric materials.
The method to combine thermoelectric(TE)and magnetocaloric(MC)cooling techniques lies in developing a new material that simultaneously possesses a large TE and good MC cooling *** this work,using n-type Bi_(2)Te_(2.7)...
详细信息
The method to combine thermoelectric(TE)and magnetocaloric(MC)cooling techniques lies in developing a new material that simultaneously possesses a large TE and good MC cooling *** this work,using n-type Bi_(2)Te_(2.7)Se_(0.3)(BTS)as the TE base material and Gd as the second-phase MC material,Gd/BTS composites were prepared by the spark plasma sintering *** the composites,interfacial reaction between Gd and BTS was identified,resulting in the formation of Gd Te,which has a large impact on the electron concentration through the adjustment of defect *** MC/TE composite containing 2.5 wt%Gd exhibited a ZT value of 0.6 at 300 K,essentially retaining the original TE performance,while all the composites largely maintained the excellent MC performance of *** work provides a potential pathway to achieving high performance in MC/TE composites.
By replacing hexyl chains in poly(3-hexylthiophene)(P3HT)with 2-propoxyethyls,four poly(3-(2-propoxyethyl)thiophene)(P3POET)homopolymers with comparable polydispersity indexes(PDI)and regioregularities were prepared h...
详细信息
By replacing hexyl chains in poly(3-hexylthiophene)(P3HT)with 2-propoxyethyls,four poly(3-(2-propoxyethyl)thiophene)(P3POET)homopolymers with comparable polydispersity indexes(PDI)and regioregularities were prepared herein in addition with step increment of about 7 kDa on numberaverage molecular weight(M_(n))from around 11 to 32 kDa(accordingly denoted as P11k,P18k,P25k,and P32k).When doped in film by FeCl_(3)at the optimized conditions,the maximum power factor(PF_(max))increases greatly from 4.3μW·m^(-1)·K^(-2)for P11k to 8.8μW·m^(-1)·K^(-2)for P18k,and further to 9.7μW·m^(-1)·K^(-2)for P25k,followed by a slight decrease to 9.2μW·m^(-1)·K^(-2)for *** close Seebeck coefficients(S)at PF_(max)are observed in these doped polymer films due to their consistent frontier orbital energy levels and Fermi *** main contribution to this PF_(max)evolution thus comes from the corresponding conductivities(σ).Theσvariation of the doped films can be rationally correlated with their microstructure evolution.
Emerging technological advances are reshaping the casting sector in latest *** technology is evolving towards intelligent casting paradigm that involves automation,greenization and intelligentization,which attracts mo...
详细信息
Emerging technological advances are reshaping the casting sector in latest *** technology is evolving towards intelligent casting paradigm that involves automation,greenization and intelligentization,which attracts more and more attention from the academic and industry *** this paper,the main features of casting technology were briefly summarized and forecasted,and the recent developments of key technologies and the innovative efforts made in promoting intelligent casting process were ***,the technical visions of intelligent casting process were also put *** key technologies for intelligent casting process comprise 3D printing technologies,intelligent mold technologies and intelligent process control *** future,the intelligent mold that derived from mold with sensors,control devices and actuators will probably incorporate the Internet of Things,online inspection,embedded simulation,decision-making and control system,and other technologies to form intelligent cyber-physical casting system,which may pave the way to realize intelligent *** is promising that the intelligent casting process will eventually achieve the goal of real-time process optimization and full-scale control,with the defects,microstructure,performance,and service life of the fabricated castings can be accurately predicted and tailored.
It is a practically significant issue to refine and modify industrial Al-Si casting alloy to improve its *** the present study,a novel refiner Al-3Ti-4.35La alloy,prepared by a melt-reaction method,was used,combined w...
详细信息
It is a practically significant issue to refine and modify industrial Al-Si casting alloy to improve its *** the present study,a novel refiner Al-3Ti-4.35La alloy,prepared by a melt-reaction method,was used,combined with Sr to refine the as-cast A356 *** effects on the as-cast microstructures and mechanical properties of A356 alloy were *** results indicate that the combined addition of Al-3Ti-4.35La intermediate alloy and Sr can improve the microstructure and enhance the mechanical properties of A356 *** adding 0.3wt.%Al-3Ti-4.35La and 0.03wt.%Sr to the as-cast A356 alloy,the average grain size ofα-Al decreases from 693.47μm to 264.13μm(a decrease of 61.91%),the secondary dendrite arm spacing(SDAS)is decreased by 47.8%from 32.09μm to 16.75μm,and the eutectic Si is transformed from an acicular structure to short rods and a granular *** ultimate tensile strength(UTS)and elongation(EL)of the as-cast A356 alloy modified by Al-3Ti-4.35La and Sr reach 216.3 MPa and 10.6%,which are enhanced by 29.54%and 134.66%compared with the unmodified alloy,*** fracture mode is transformed from transgranular fracture to intergranular fracture,and the ductile toughness of the alloy is *** adding the Al-3Ti-4.35La and Sr,the undercooling for the nucleation ofα-Al and eutectic Si increases,leading to an accelerated nucleation rate and an increased number of nuclei,which shortens the duration of the eutectic reaction and consequently inhibits grain growth.
暂无评论