Exploring cathode materials that combine excellent cycling stability and high energy density poses a challenge to aqueous Zn-ion hybrid supercapacitors(ZHSCs).Herein,polyaniline(PANI)coated boron-carbon-nitrogen(BCN)n...
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Exploring cathode materials that combine excellent cycling stability and high energy density poses a challenge to aqueous Zn-ion hybrid supercapacitors(ZHSCs).Herein,polyaniline(PANI)coated boron-carbon-nitrogen(BCN)nanoarray on carbon cloth surface is prepared as advanced cathode materials via simple high-temperature calcination and electrochemical deposition *** of the excellent specific capacity and conductivity of PANI,the CC@BCN@PANI core-shell nanoarrays cathode shows an excellent ion storage ***,the 3D nanoarray structure can provide enough space for the volume expansion and contraction of PANI in the charging/discharging cycles,which effectively avoids the collapse of the microstructure and greatly improves the electrochemical stability of ***,the CC@BCN@PANI-based ZHSCs exhibit superior electrochemical performances showing a specific capacity of 145.8 mAh/g,a high energy density of 116.78 Wh/kg,an excellent power density of 12 kW/kg,and a capacity retention rate of 86.2%after 8000 charge/discharge cycles at a current density of 2 A/*** addition,the flexible ZHSCs(FZHSCs)also show a capacity retention rate of 87.7%at the current density of 2 A/g after 450 cycles.
Cohesive zone plays a vital role in the stable operation of a blast furnace(BF),yet the complex phase change process of iron ore particles in this zone is still not well *** this study,a novel one-dimensional(1D)unste...
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Cohesive zone plays a vital role in the stable operation of a blast furnace(BF),yet the complex phase change process of iron ore particles in this zone is still not well *** this study,a novel one-dimensional(1D)unsteady phase change model was developed to elucidate the heat transfer and melting mechanisms of iron ore *** model validation,the effects of several key operating parameters(e.g.,particle diameter,gas velocity,initial temperature)on the phase change behavior of iron ore particles were analyzed,and the joint effect of multiple parameters was *** results show that larger-sized iron ore particles possess lower specific surface areas,which in turn reduces their convective heat absorption ***,the distance from the solid-liquid phase interface to the particle surface increases,thereby slowing down the movement of the phase interface and pro-longing the melting duration of the *** the gas velocity and the initial temperature does not have a significant impact on reducing the duration of the complete melting *** the specified conditions,it is observed that increasing the gas velocity by 3-fold and 9-fold results in a reduction of the melting duration by 2.4%and 8.3%,*** the initial temperature of iron ore particles results in a decrease in the core-to-surface temperature difference,a slower heating rate,and a shorter duration to achieve *** the factors affecting the melting process,the particle diameter is found to be the most significant in terms of the liquid phase precipitation,mushy zone thickness,and core-to-surface temperature difference of iron ore particles.
The methane combustion with hydrogen addition can effectively reduce carbon emissions in the iron and steel making industry,while the combustion mechanism is still poorly *** oxy-fuel combustion of methane with hydrog...
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The methane combustion with hydrogen addition can effectively reduce carbon emissions in the iron and steel making industry,while the combustion mechanism is still poorly *** oxy-fuel combustion of methane with hydrogen addition in a 0.8 MW oxy-natural gas combustion experimental furnace was numerically studied to investigate six different combustion *** results show that the 28-step chemical reaction mechanism is the optimal recommendation for the simulation balancing the numerical accuracy and computational *** the hydrogen enrichment increases in fuel,the highest flame temperature ***,the chemical reaction accelerates with enlarging the peak of the highest flame temperature and intermediate OH *** the hydrogen enrichment reaches 75 vol.%,the flame front is the farthest,and the flame high-temperature zone occupies the largest proportion corresponding to the most vigorous chemical reactions in the same oxygen supply.
In this paper,the gas and seed flow characters in the air-blowing seed metering device are investigated by using the coupled computational fluid dynamics and discrete element method(CFD-DEM)in three dimensions(3D).The...
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In this paper,the gas and seed flow characters in the air-blowing seed metering device are investigated by using the coupled computational fluid dynamics and discrete element method(CFD-DEM)in three dimensions(3D).The method of establishing boundary model based on the computer-aided design(CAD)drawing,has been used to build the boundary model of seed metering *** 3D laser scanning technique and multi-element method are adopted to establish the particle *** a combined numerical and experimental effort,using 3D CFD-DEM software,which is based on the in-house codes,the mechanisms governing the gas and solid dynamic behaviors in the seed metering device have been *** gas velocity field and the effect of different rotational speeds and air pressures on the seeding performance and particle velocity have been studied,similar agreements between numerical and experimental results are *** reveals that the 3D CFD-DEM model established is able to predict the performance of the air-blowing seed metering *** can be used to design and optimize the air-blowing seed metering device and other similar agriculture devices.
Spouted bed has drawn much attention due to its good heat and mass transfer efficiency in many chemical *** the flow patterns and heat and mass transfer inside a spouted bed can help optimize the spouting ***,in this ...
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Spouted bed has drawn much attention due to its good heat and mass transfer efficiency in many chemical *** the flow patterns and heat and mass transfer inside a spouted bed can help optimize the spouting ***,in this study,the effects of particle shape on the hydrodynamics and heat transfer in a spouted bed are *** is done by using a validated computational fluid dynamics-discrete element method(CFD-DEM)model,considering volume-equivalent spheres and oblate and prolate *** results are analysed in detail in terms of the flow pattern,microstruc-ture,and heat transfer *** numerical results show that the prolate spheroids(Ar=2.4)form the largest bubble from the beginning of the spouting process and rise the highest because the fluid drag forces can overcome the interlocking and particle-particle frictional *** with spherical particles,ellipsoidal spheroids have better mobility because of the stronger rotational kinetic energy resulting from the rough surfaces and nonuniform *** addition,the oblate spheroid system exhibits better heat transfer performance benefiting from the larger surface area,while prolate spheroids have poor heat transfer efficiency because of their orientation *** findings can serve as a reference for optimizing the design and operation of complex spouted beds.
Exploring cathode materials that combine excellent cycling stability and high energy density remains challenging for aqueous zinc ion hybrid supercapacitors (ZHSCs). Herein, polyaniline (PANI) coated BCN nanoarray on ...
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Strict control of powder properties,especially particle size distribution(PSD),is critical in the laser powder bed fusion(LPBF)process to ensure the quality of the fabricated *** work shows that reducing the powder si...
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Strict control of powder properties,especially particle size distribution(PSD),is critical in the laser powder bed fusion(LPBF)process to ensure the quality of the fabricated *** work shows that reducing the powder size could improve the ductility of LPBF fabricated *** tensile elongation increased from 4.1%to 8.8%when AlSi10Mg powder sizes(D50 value)decreased from 76μm to 16μm in the as-fabricated *** results showed that fine powder size stimulates epitaxial grain growth due to excessive *** presence of epitaxial columnar grains makes the crack path across inner melt pools more frequent and travels from the coarse melt pool zones to the fine melt pool *** work suggests that powder size is a crucial factor to be considered in maintaining repeatable mechanical properties in LPBF processes,particularly when ductility and ductility-dominated properties are critical.
The rapid advancement of modern industry and aerospace has imposed demands on thermal insulators to possess not only efficient isolation but also multifunctionality. Polybenzoxazine (PBz) aerogels with several advanta...
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Polybenzoxazine aerogels have gained widespread attention in recent years, but the prevalent use of hazardous solvents in the preparation process has severely impeded their further development and promotion for practi...
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