Mask image projection-based vat photopolymerization(MIP-VPP)offers advantages like low cost,high resolution,and a wide material range,making it popular in industry and education.Recently,MIP-VPP employing liquid cryst...Mask image projection-based vat photopolymerization(MIP-VPP)offers advantages like low cost,high resolution,and a wide material range,making it popular in industry and education.Recently,MIP-VPP employing liquid crystal displays(LCDs)has gained traction,increasingly replacing digital micromirror devices,particularly among hobbyists and in educational settings,and is now beginning to be used in industrial environments.However,LCD-based MIP-VPPsuffers from pronounced pixelated aliasing arising from LCD’s discrete image pixels and itsdirect-contact configuration in MIP-VPP machines,leading to rough surfaces on the 3D-printed parts.Here,we propose a vibration-assisted MIP-VPP method that utilizes a microscalevibration to uniformize the light intensity distribution of the LCD-based mask image on VPP’s building platform.By maintaining the same fabrication speed,our technique generates asmoother,non-pixelated mask image,reducing the roughness on flat surfaces and boundary segments of 3D-printed parts.Through light intensity modeling and simulation,we derived an optimal vibration pattern for LCD mask images,subsequently validated by experiments.We assessed the surface texture,boundary integrity,and dimensional accuracy of componentsproduced using the vibration-assisted approach.The notably smoother surfaces and improved boundary roughness enhance the printing quality of MIP-VPP,enabling its promisingapplications in sectors like the production of 3D-printed optical devices and others.展开更多
The solvent-free in situ polymerization technique has the potential to tailor-make conformal interfaces that are essential for developing durable and safe lithium metal polymer batteries(LMPBs).Hence,much attention ha...The solvent-free in situ polymerization technique has the potential to tailor-make conformal interfaces that are essential for developing durable and safe lithium metal polymer batteries(LMPBs).Hence,much attention has been given to the eco-friendly and rapid ultraviolet(UV)-induced in situ photopolymerization process to prepare solid-state polymer electrolytes.In this respect,an innovative method is proposed here to overcome the challenges of UV-induced photopolymerization(UV-curing)in the zones where UV-light cannot penetrate,especially in LMPBs where thick electrodes are used.The proposed frontal-inspired photopolymerization(FIPP)process is a diverged frontal-based technique that uses two classes(dual)of initiators to improve the slow reaction kinetics of allyl-based monomers/oligomers by at least 50%compared with the conventional UV-curing process.The possible reaction mechanism occurring in FIPP is demonstrated using density functional theory calculations and spectroscopic investigations.Indeed,the initiation mechanism identified for the FIPP relies on a photochemical pathway rather than an exothermic propagating front forms during the UV-irradiation step as the case with the classical frontal photopolymerization technique.Besides,the FIPP-based in situ cell fabrication using dual initiators is advantageous over both the sandwich cell assembly and conventional in situ photopolymerization in overcoming the limitations of mass transport and active material utilization in high energy and high power LMPBs that use thick electrodes.Furthermore,the LMPB cells fabricated using the in situ-FIPP process with high mass loading LiFePO_(4)electrodes(5.2 mg cm^(-2))demonstrate higher rate capability,and a 50%increase in specific capacity against a sandwich cell encouraging the use of this innovative process in large-scale solid-state battery production.展开更多
虚拟电厂(virtual power plant,VPP)可以聚合多元异构分布式能源(distributed energy resource,DER)灵活参与电力市场,但受市场多元主体投标行为不确定性的影响,VPP在日前电力市场面临着潜在的投标需求流标风险。为解决多元竞争电力市...虚拟电厂(virtual power plant,VPP)可以聚合多元异构分布式能源(distributed energy resource,DER)灵活参与电力市场,但受市场多元主体投标行为不确定性的影响,VPP在日前电力市场面临着潜在的投标需求流标风险。为解决多元竞争电力市场中电价电量不确定性影响下VPP的优化申报问题,提出一种VPP灵活分段投标策略。首先,基于分布式能源运行特性构建了虚拟电厂聚合可调节能力评估方法,在考虑电力平衡需求的基础上,提出按可调节能力划分区间的VPP灵活分段投标策略。然后,构建了虚拟电厂参与日前电力现货市场投标的主从博弈模型,以实现VPP收益及社会效益的最大化。最后,采用强对偶理论和大M法将该均衡约束规划问题(equilibrium problems with equilibrium constraints,EPEC)转化为混合整数线性规划问题(mixed integer linear program,MILP)求解。算例结果表明,VPP采用灵活分段投标策略参与日前电力市场,可以充分利用其可调节能力,保障其投标需求有效中标,有效提升了VPP收益及社会效益。展开更多
文摘Mask image projection-based vat photopolymerization(MIP-VPP)offers advantages like low cost,high resolution,and a wide material range,making it popular in industry and education.Recently,MIP-VPP employing liquid crystal displays(LCDs)has gained traction,increasingly replacing digital micromirror devices,particularly among hobbyists and in educational settings,and is now beginning to be used in industrial environments.However,LCD-based MIP-VPPsuffers from pronounced pixelated aliasing arising from LCD’s discrete image pixels and itsdirect-contact configuration in MIP-VPP machines,leading to rough surfaces on the 3D-printed parts.Here,we propose a vibration-assisted MIP-VPP method that utilizes a microscalevibration to uniformize the light intensity distribution of the LCD-based mask image on VPP’s building platform.By maintaining the same fabrication speed,our technique generates asmoother,non-pixelated mask image,reducing the roughness on flat surfaces and boundary segments of 3D-printed parts.Through light intensity modeling and simulation,we derived an optimal vibration pattern for LCD mask images,subsequently validated by experiments.We assessed the surface texture,boundary integrity,and dimensional accuracy of componentsproduced using the vibration-assisted approach.The notably smoother surfaces and improved boundary roughness enhance the printing quality of MIP-VPP,enabling its promisingapplications in sectors like the production of 3D-printed optical devices and others.
基金The support provided by the German Federal Ministry of Education and Research(BMBF)within the project“Benchbatt”(03XP0047B)is gratefully acknowledged.
文摘The solvent-free in situ polymerization technique has the potential to tailor-make conformal interfaces that are essential for developing durable and safe lithium metal polymer batteries(LMPBs).Hence,much attention has been given to the eco-friendly and rapid ultraviolet(UV)-induced in situ photopolymerization process to prepare solid-state polymer electrolytes.In this respect,an innovative method is proposed here to overcome the challenges of UV-induced photopolymerization(UV-curing)in the zones where UV-light cannot penetrate,especially in LMPBs where thick electrodes are used.The proposed frontal-inspired photopolymerization(FIPP)process is a diverged frontal-based technique that uses two classes(dual)of initiators to improve the slow reaction kinetics of allyl-based monomers/oligomers by at least 50%compared with the conventional UV-curing process.The possible reaction mechanism occurring in FIPP is demonstrated using density functional theory calculations and spectroscopic investigations.Indeed,the initiation mechanism identified for the FIPP relies on a photochemical pathway rather than an exothermic propagating front forms during the UV-irradiation step as the case with the classical frontal photopolymerization technique.Besides,the FIPP-based in situ cell fabrication using dual initiators is advantageous over both the sandwich cell assembly and conventional in situ photopolymerization in overcoming the limitations of mass transport and active material utilization in high energy and high power LMPBs that use thick electrodes.Furthermore,the LMPB cells fabricated using the in situ-FIPP process with high mass loading LiFePO_(4)electrodes(5.2 mg cm^(-2))demonstrate higher rate capability,and a 50%increase in specific capacity against a sandwich cell encouraging the use of this innovative process in large-scale solid-state battery production.
文摘虚拟电厂(virtual power plant,VPP)可以聚合多元异构分布式能源(distributed energy resource,DER)灵活参与电力市场,但受市场多元主体投标行为不确定性的影响,VPP在日前电力市场面临着潜在的投标需求流标风险。为解决多元竞争电力市场中电价电量不确定性影响下VPP的优化申报问题,提出一种VPP灵活分段投标策略。首先,基于分布式能源运行特性构建了虚拟电厂聚合可调节能力评估方法,在考虑电力平衡需求的基础上,提出按可调节能力划分区间的VPP灵活分段投标策略。然后,构建了虚拟电厂参与日前电力现货市场投标的主从博弈模型,以实现VPP收益及社会效益的最大化。最后,采用强对偶理论和大M法将该均衡约束规划问题(equilibrium problems with equilibrium constraints,EPEC)转化为混合整数线性规划问题(mixed integer linear program,MILP)求解。算例结果表明,VPP采用灵活分段投标策略参与日前电力市场,可以充分利用其可调节能力,保障其投标需求有效中标,有效提升了VPP收益及社会效益。