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“Announcement on Deepening the Value-Added Tax Reform”clearly outlines the preferential policy regarding incremental retention tax rebates.With the advancement of value-added tax(VAT)reform and the improvement of...The“Announcement on Deepening the Value-Added Tax Reform”clearly outlines the preferential policy regarding incremental retention tax rebates.With the advancement of value-added tax(VAT)reform and the improvement of VAT legislation in China,VAT tax planning for construction enterprises,particularly related to retained tax credits,has become routine.This paper,focusing on the characteristics of construction enterprises,analyzes VAT retained tax credits at the end of the period,the status of tax refunds,practical issues,and related processes,and offers suggestions for policy application and risk prevention.展开更多
Rechargeable sodium metal batteries constitute a cost-effective option for energy storage although sodium shows some drawbacks in terms of reactivity with organic solvents and dendritic growth.Here we demonstrate that...Rechargeable sodium metal batteries constitute a cost-effective option for energy storage although sodium shows some drawbacks in terms of reactivity with organic solvents and dendritic growth.Here we demonstrate that an organic dye,indanthrone blue,behaves as an efficient cathode material for the development of secondary sodium metal batteries when combined with novel inorganic electrolytes.These electrolytes are ammonia solvates,known as liquid ammoniates,which can be formulated as NaI·3.3NH_(3) and NaBF_(4)·2.5NH_(3).They impart excellent stability to sodium metal,and they favor sodium non-dendritic growth linked to their exceedingly high sodium ion concentration.This advantage is complemented by a high specific conductivity.The battery described here can last hundreds of cycles at 10 C while keeping a Coulombic efficiency of 99%from the first cycle.Because of the high capacity of the cathode and the superior physicochemical properties of the electrolytes,the battery can reach a specific energy value as high as 210 W h kgIB^(-1),and a high specific power of 2.2 kW kgIB^(-1),even at below room temperature(4℃).Importantly,the battery is based on abundant and cost-effective materials,bearing promise for its application in large-scale energy storage.展开更多
目的通过研究Ⅲ度房室传导阻滞患者高位右室间隔部起搏(HRVS)时,VAT与DDD模式对心功能的影响,探讨心房的生理收缩和舒张对左心功能的作用。方法 32例Ⅲ度房室传导阻滞患者,在HRVS时,分别给予DDD模式或VAT模式工作,于调控即刻通过超声心...目的通过研究Ⅲ度房室传导阻滞患者高位右室间隔部起搏(HRVS)时,VAT与DDD模式对心功能的影响,探讨心房的生理收缩和舒张对左心功能的作用。方法 32例Ⅲ度房室传导阻滞患者,在HRVS时,分别给予DDD模式或VAT模式工作,于调控即刻通过超声心动图测定二尖瓣口快速充盈期峰值血流速度(Ep),二尖瓣口左房收缩期峰值血流速度(Ap),二尖瓣环后壁处收缩期脉冲组织多普勒峰值速度平均值(Vs),二尖瓣环后壁处舒张早期脉冲组织多普勒峰值速度平均值(Ve),二尖瓣环后壁处舒张晚期脉冲组织多普勒峰值速度平均值(Va),二尖瓣血流频谱等容舒张时间(IVRT),通过Ep/Ap,Ve/Va,Ep/Ve和IVRT评价左室舒张功能,通过Vs,LVEF和LVFS评价收缩功能。结果 HRVS时DDD较VAT模式Ep/Ap、Ve/Va、Ep/Ve,IVRT差异有显著性(0.97±0.11 vs 1.01±0.11,0.89±0.09 vs 0.97±0.07,6.00±0.45 vs 6.24±0.36,100.4±14.32 vs 89.99±7.94;P均<0.01),Vs、左室射血分数和左室短轴缩短率无显著性差异。结论Ⅲ度房室传导阻滞时,HRVS起搏时,DDD模式较VAT模式使左室舒张功能下降,收缩功能无影响,表明了心房生理性起搏的重要性。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.
文摘The“Announcement on Deepening the Value-Added Tax Reform”clearly outlines the preferential policy regarding incremental retention tax rebates.With the advancement of value-added tax(VAT)reform and the improvement of VAT legislation in China,VAT tax planning for construction enterprises,particularly related to retained tax credits,has become routine.This paper,focusing on the characteristics of construction enterprises,analyzes VAT retained tax credits at the end of the period,the status of tax refunds,practical issues,and related processes,and offers suggestions for policy application and risk prevention.
基金developed in the context of project RTI2018–102061–B–I00 financed by FEDER/Ministerio de Ciencia e Innovación-Agencia Estatal de InvestigaciónThe Generalitat Valenciana through project PROMETEO/2020/089 is also gratefully acknowledged。
文摘Rechargeable sodium metal batteries constitute a cost-effective option for energy storage although sodium shows some drawbacks in terms of reactivity with organic solvents and dendritic growth.Here we demonstrate that an organic dye,indanthrone blue,behaves as an efficient cathode material for the development of secondary sodium metal batteries when combined with novel inorganic electrolytes.These electrolytes are ammonia solvates,known as liquid ammoniates,which can be formulated as NaI·3.3NH_(3) and NaBF_(4)·2.5NH_(3).They impart excellent stability to sodium metal,and they favor sodium non-dendritic growth linked to their exceedingly high sodium ion concentration.This advantage is complemented by a high specific conductivity.The battery described here can last hundreds of cycles at 10 C while keeping a Coulombic efficiency of 99%from the first cycle.Because of the high capacity of the cathode and the superior physicochemical properties of the electrolytes,the battery can reach a specific energy value as high as 210 W h kgIB^(-1),and a high specific power of 2.2 kW kgIB^(-1),even at below room temperature(4℃).Importantly,the battery is based on abundant and cost-effective materials,bearing promise for its application in large-scale energy storage.
文摘目的通过研究Ⅲ度房室传导阻滞患者高位右室间隔部起搏(HRVS)时,VAT与DDD模式对心功能的影响,探讨心房的生理收缩和舒张对左心功能的作用。方法 32例Ⅲ度房室传导阻滞患者,在HRVS时,分别给予DDD模式或VAT模式工作,于调控即刻通过超声心动图测定二尖瓣口快速充盈期峰值血流速度(Ep),二尖瓣口左房收缩期峰值血流速度(Ap),二尖瓣环后壁处收缩期脉冲组织多普勒峰值速度平均值(Vs),二尖瓣环后壁处舒张早期脉冲组织多普勒峰值速度平均值(Ve),二尖瓣环后壁处舒张晚期脉冲组织多普勒峰值速度平均值(Va),二尖瓣血流频谱等容舒张时间(IVRT),通过Ep/Ap,Ve/Va,Ep/Ve和IVRT评价左室舒张功能,通过Vs,LVEF和LVFS评价收缩功能。结果 HRVS时DDD较VAT模式Ep/Ap、Ve/Va、Ep/Ve,IVRT差异有显著性(0.97±0.11 vs 1.01±0.11,0.89±0.09 vs 0.97±0.07,6.00±0.45 vs 6.24±0.36,100.4±14.32 vs 89.99±7.94;P均<0.01),Vs、左室射血分数和左室短轴缩短率无显著性差异。结论Ⅲ度房室传导阻滞时,HRVS起搏时,DDD模式较VAT模式使左室舒张功能下降,收缩功能无影响,表明了心房生理性起搏的重要性。
