The global annual production of poly(ethylene terephthalate)(PET)has reached 82 million tons,yet only a small fraction(less than 20%)is *** ultra-slow degradation rate of PET results in the accumulation of PET waste i...
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The global annual production of poly(ethylene terephthalate)(PET)has reached 82 million tons,yet only a small fraction(less than 20%)is *** ultra-slow degradation rate of PET results in the accumulation of PET waste in the environment,causing serious plastic pollution and posing severe challenges to *** response,great efforts have been directed toward developing a cascade degradation and electrocatalytic upcycling strategy,which serves as a“waste-towealth”*** strategy involves electro-reforming PEThydrolyzed intermediates or using PET pyrolyzed products as electrocatalysts to generate high-value *** review provides an overview of the state-of-the-art strategies for the“degradation-electrocatalytic upcycling(De-eUp)”of PET ***,an introduction to the strategy is provided,categorizing it into two main frameworks:“pyrolysis-electrocatalytic upcycling”and“hydrolysis-electrocatalytic upcycling”.The section on“pyrolysis-electrocatalytic upcycling”delves into the degradation methods for designing derived carbon nanomaterials and their utilization as high-performance ***“hydrolysis-electrocatalytic upcycling”section discusses recent advancements in electro-reforming of PET hydrolyzed intermediates for the production of C_(1) and C_(2) *** review concludes by examining the challenges and future prospects in developing an efficient and economical PET upcycling *** is anticipated that this review will stimulate further progress in plastic waste valorization.
Cement-based materials are the foundation of modern buildings but suffer from intensive energy *** cement-based materials for efficient energy storage is one of the most promising strategies for realizing zero-energy ...
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Cement-based materials are the foundation of modern buildings but suffer from intensive energy *** cement-based materials for efficient energy storage is one of the most promising strategies for realizing zero-energy ***,cement-based materials encounter challenges in achieving excellent electrochemical performance without compromising mechanical ***,we introduce a biomimetic cement-based solid-state electrolyte(labeled as l-CPSSE)with artificially organized layered microstructures by proposing an in situ ice-templating strategy upon the cement hydration,in which the layered micropores are further filled with fast-ion-conducting hydrogels and serve as ion diffusion *** these merits,the obtained l-CPSSE not only presents marked specific bending and compressive strength(2.2 and 1.2 times that of traditional cement,respectively)but also exhibits excellent ionic conductivity(27.8 mS·cm^(-1)),overwhelming most previously reported cement-based and hydrogel-based *** a proof-of-concept demonstration,we assemble the l-CPSSE electrolytes with cement-based electrodes to achieve all-cement-based solid-state energy storage devices,delivering an outstanding full-cell specific capacity of 72.2 mF·cm^(-2).More importantly,a 5×5 cm^(2) sized building model is successfully fabricated and operated by connecting 4 l-CPSSE-based full cells in series,showcasing its great potential in self-energy-storage *** work provides a general methodology for preparing revolutionary cement-based electrolytes and may pave the way for achieving zero-carbon buildings.
Differing from the statically precipitated grain boundary α(GBα) that holds Burgers Orientation Relationship(BOR) with adjacent β grains, in this work, it was found that over 97.77 % of the dynamically precipitated...
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Differing from the statically precipitated grain boundary α(GBα) that holds Burgers Orientation Relationship(BOR) with adjacent β grains, in this work, it was found that over 97.77 % of the dynamically precipitated GBαs do not hold BOR with either side of the adjacent β grains in hot-forged Ti-652 titanium alloy. The evolution of GBα orientation was decoupled as dynamic precipitation and annihilation, which was quantitatively distinguished by defining three misorientation angles: the deviation form BOR(ω), the misorientation between adjacent β grains(θ) and the misorientation between non-BOR GBαs(θ'). During the entire hot forging, an adequate dynamic precipitation produces piecewise continuous and slender GBαs with ω <10°typically, manifesting as θ <25°but θ'>45°. Oppositely, a sufficient annihilation leads to the dynamic globularization of GBαs and increase of ω with θ≥25°but mainly θ'≤45°. Dynamic precipitation was driven by the intrinsic BOR preference of GBαs, while annihilation attributed to grain growth and rotation caused by accumulated plastic deformation. Deciphering the dynamic precipitation and annihilation of GBα provides a quantitative criterion to tailor microstructures and mechanical properties in the future.
In this paper, the microstructure evolution and properties of squeeze-cast Al–8Si-1.5Cu–1Ni-0.5Mg-0.5Mn-0.2V-0.2Ti-0.2Zr alloy（hereafter, Al–Si–Cu–Ni alloy for short） were investigated under various solution pr...
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In this paper, the microstructure evolution and properties of squeeze-cast Al–8Si-1.5Cu–1Ni-0.5Mg-0.5Mn-0.2V-0.2Ti-0.2Zr alloy（hereafter, Al–Si–Cu–Ni alloy for short） were investigated under various solution processes,evaluating the mechanical properties at room and elevated temperatures for both as-cast and T6-treated *** results showed that following the optimal two-stage solution（i.e., solution at 510°C for 6 h + solution at 530°C for 8 h） and subsequent aging at 190°C for 10 h, referred to as the S530-T6 treatment, the Al–Si–Cu–Ni alloy exhibited excellent room/high temperature performance. The ultimate tensile strength（UTS）, yield strength（YS）and elongation of the alloy at room temperature were 410 MPa, 368 MPa and 1.5 %, and the UTS, YS and elongation of alloy at 300°C were 177 MPa, 170 MPa and 6 %, respectively. The increase in strength at room temperature is mainly attributed to the spheroidization of eutectic silicon and the precipitate strengthening aroused from uniformly dispersed nano-sized Q-Al4Cu2Mg8Si7, σ-Al5Cu6Mg2and θ'-Al2Cu phases, while the increase in strength at high temperature is due to the formation of heat-resistant Ni-rich phases and the improvement of the micromorphology of high melting point intermetallic compounds.
This work reports a high strength and ductility as-casted Mg-9Gd-1.5Y-0.8Zn-0.3Zr(wt.%) alloy by using the optimized heat treatment of a lower solid-solution temperature of 480°C and then aging at 200°C for ...
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This work reports a high strength and ductility as-casted Mg-9Gd-1.5Y-0.8Zn-0.3Zr(wt.%) alloy by using the optimized heat treatment of a lower solid-solution temperature of 480°C and then aging at 200°C for 48 h with the ultimate tensile strength and yield strength reached 374(±2.0) MPa and 270.5(±5.5) MPa, respectively,whilst a high elongation of 10.1(±1.3) % was achieved. The high strength and ductility are found to emerged primarily from the synergic influence of long period stacking ordered(LPSO) phases and the nano-β'precipitates:at lower temperature of 480°C the alloy preserved a large number of block and lamellar 14H-LPSO phases at the grain boundaries and the smallest size of β'precipitates led to a better ductility and higher strength. While at higher temperatures solid-solution treatment of 500°C and 520°C, the strength and ductility declined slightly due to the lamellar or filminess LPSO formed in the grains, and especially the precipitation of cubic-shaped REenriched phases and rod-like Zn–Zr compounds. Particularly when the solid solution temperature reached as high as 520°C, the strength was significantly reduced due to the increase of the cubic-shaped RE-enriched phases. We suppose that the efficiency of the morphology and position of LPSO phases on the ductility strengthening of the alloy is block and lamellar LPSO phases in the grain boundaries > lamellar or filminess LPSO phases in the grains.
The influence of micro-Ca/In alloying on the microstructural charac teristics,electrochemical behaviors and discharge properties of extruded dilute Mg-0.5Bi-0.5Sn-based(wt.%)alloys as anodes for Mg-air batteries are *...
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The influence of micro-Ca/In alloying on the microstructural charac teristics,electrochemical behaviors and discharge properties of extruded dilute Mg-0.5Bi-0.5Sn-based(wt.%)alloys as anodes for Mg-air batteries are *** grain size and texture intensity of the Mg-Bi-Sn-based alloys are significantly decreased after the Ca/In alloying,particularly for the In-containing *** that,in addition to nanoscale Mg_(3)Bi_(2)phase,a new microscale Mg_(2)Bi_(2)Ca phase forms in the Ca-containing *** electrochemical test results demonstrate that Ca/In micro-alloying can enhance the electrochemical *** In to alloy the Mg-Bi-Sn-based alloy is effective in restricting the cathodic hydrogen evolution(CHE)kinetics,leading to a low self-corrosion rate,while severe CHE occurred after Ca *** micro-alloying of Ca/In to Mg-Bi-Sn-based alloy strongly deteriorates the compactness of discharge products film and mitigates the"chunk effect"(CE),hence the cell voltage,anodic efficiency as well as discharge capacity are greatly *** In-containing alloy exhibits outstanding discharge performance under the combined effect of the modified microstructure and discharge products,thus making it a potential anode material for primary Mg-air battery.
With the further requirements of electronic products and powered vehicles,the development of a new generation with low-voltage and high-capacity anode materials is crucial for lithium-ion batteries(LIBs).Transition me...
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With the further requirements of electronic products and powered vehicles,the development of a new generation with low-voltage and high-capacity anode materials is crucial for lithium-ion batteries(LIBs).Transition metal phosphides,especially cobalt phosphide(CoP)composites,have become a research hotspot for LIBs anode materials in recent years due to their high theoretical specific capacity,low polarization,and suitable voltage *** review first systematically discusses the lithium storage mechanism and preparation methods of CoP in current ***,the applications of CoP anode materials in LIBs are categorically reviewed,including the composites of CoP with various types of carbon materials and ***,the challenges and future development directions of CoP anode materials are summarized to provide guidance for further improving the lithium storage performance of CoP and its practical applications.
Municipal solid waste incineration fly ash(MSWI)is considered as one of the hazardous wastes and requires to be well disposed to reduce the contaminant to the *** to the production of coal fly ash(FA)bricks,MSWI and F...
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Municipal solid waste incineration fly ash(MSWI)is considered as one of the hazardous wastes and requires to be well disposed to reduce the contaminant to the *** to the production of coal fly ash(FA)bricks,MSWI and FA were utilized to prepare autoclaved MSWI-FA block ***-assisted hydrothermal synthesis technology was used for production to explore the effect of ultrasonic *** strength,dry density,and water absorption tests were conducted to determine the optimal ultrasonic *** pre-treating mechanisms were investigated by SEM,FT-IR,particle size analysis,and ***,the micro-analyses of block samples were *** heavy metal leaching concentration was studied to assess the environmental *** experimental results show that the ultrasonic pre-treating time,water bath temperature,and ultrasonic power of 3 h,30℃,and 840 W are the optimal,under which the compressive strength,dry density,and water absorption were 8.14 MPa,1417.48 kg/m^(3),and 0.38,*** is shown that ultrasound destroys the surface structure of raw materials and smaller FA particles embed into *** particle size distribution of pre-treated raw materials mixture is wider and total pore volume is decreased by 6.3%.During hydrothermal processing,more Al-substituted tobermorite crystals are generated,which is the main source of higher strength and smaller pore volume of prepared block *** solidification/stabilization rates of Cu,Pb,and Zn increased by 30.77%,4.76%,and 35.29%,*** study shows a feasible way to utilize MSWI as raw material for construction.
Design of heat treatments is related to the key technology for development of nickel-based single crystal superalloys(Ni-SXs). Based on the full understanding of the solidification characteristics, this work applies o...
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Design of heat treatments is related to the key technology for development of nickel-based single crystal superalloys(Ni-SXs). Based on the full understanding of the solidification characteristics, this work applies optimization design of heat treatments for a second-generation Ni-SX. Microstructure evolution and creep properties are compared in the material under conventional/standard(Std.) and optimized(Opt.) treatments. For the Std. sample,strong dendritic segregations determine inconsistent microstructure evolution in the dendritic(D) and interdendritic region(ID), while the latter serves as weak area to have the prior microcrack initiation, damaging overall performance of the alloy. The Opt. treatment applies higher homogenization temperature, leading to overall reduced segregations, while not inducing incipient melting. A lower temperature of first-step ageing is used to lower the size ofγ'particles. These help to form the more uniform microstructure in dendritic and interdendritic region and relieve the inconsistent microstructure evolution. The balanced local strength makes ID no longer as the weak area,thus restricting microcrack initiation. Great improvement of high temperature and low stress property is obtained by this progress, leading to the pronounced increase of creep rupture life under 1100 °C/140 MPa.
Given the carbon peak and carbon neutrality era,there is an urgent need to develop high-strength steel with remarkable hydrogen embrittlement *** is crucial in enhancing toughness and ensuring the utilization of hydro...
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Given the carbon peak and carbon neutrality era,there is an urgent need to develop high-strength steel with remarkable hydrogen embrittlement *** is crucial in enhancing toughness and ensuring the utilization of hydrogen in emerging iron and steel ***,the pursuit of enhanced metallic materials presents a cross-disciplinary scientific and engineering *** high-strength,toughened steel with both enhanced strength and hydrogen embrittlement(HE)resistance holds significant theoretical and practical *** ensures secure hydrogen utilization and further carbon neutrality objectives within the iron and steel *** on the design principles of high-strength steel HE resistance,this review provides a comprehensive overview of research on designing surface HE resistance and employing nanosized precipitates as intragranular hydrogen *** also proposes feasible recommendations and prospects for designing high-strength steel with enhanced HE resistance.
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