钠离子电池被广泛研究用于储能应用,但实现同时具有高能量密度、稳定性和快速充放电性能的正极材料仍然是一个关键的挑战。本研究合成了一系列NASICON型Na_(3.5−x)Mn_(0.5)V_(1.5−x)Zrx(PO_(4))_(3)/C材料,并掺入Mn、V和Zr元素探讨其对...钠离子电池被广泛研究用于储能应用,但实现同时具有高能量密度、稳定性和快速充放电性能的正极材料仍然是一个关键的挑战。本研究合成了一系列NASICON型Na_(3.5−x)Mn_(0.5)V_(1.5−x)Zrx(PO_(4))_(3)/C材料,并掺入Mn、V和Zr元素探讨其对电化学性能的影响。通过在Mn和V的基础上引入Zr,提出一种激活V4+/V5+氧化还原反应新的策略,从而提升能量密度。此外,Zr掺入通过拓宽离子通道并产生额外的钠离子空位,显著促进钠离子迁移,增强电极反应动力学和整体性能。结果表明,Na_(3.5−x)Mn_(0.5)V_(1.5−x)Zrx(PO_(4))_(3)/C材料表现出优异的循环稳定性,在800次循环后保持90%的容量,并具备高倍率性能(20C时,放电比容量为84 m Ah·g^(-1)),显著优于原始的Na_(3.5−x)Mn_(0.5)V_(1.5−x)Zrx(PO_(4))_(3)/C材料。该研究为开发高效且可持续钠离子电池提供了有效途径。展开更多
Objective Reversed U-curve and nonreversed U-curve(conventional technique) were both reported to be effective in treating pulmonary sinus cusp (PSC)-derived ventricular arrhythmia (VA).The aim of this study was to eva...Objective Reversed U-curve and nonreversed U-curve(conventional technique) were both reported to be effective in treating pulmonary sinus cusp (PSC)-derived ventricular arrhythmia (VA).The aim of this study was to evaluate the characteristics between two methods.展开更多
Background and Objective Ablation within the pulmonary sinus of Valsalva (PSV) becomes increasingly common in certain ventricular outflow arrhythmia. Understanding the regional anatomy is intensively concerned to avoi...Background and Objective Ablation within the pulmonary sinus of Valsalva (PSV) becomes increasingly common in certain ventricular outflow arrhythmia. Understanding the regional anatomy is intensively concerned to avoid procedure complications. The purpose of this study is to describe the anatomic relationships of PSV to its adjacent structures using computed tomographic coronary angiograms (CTCA).展开更多
Background and Objective Cardiac pacing is an effective therapy in patients with bradycardia.Conventional right ventricular(RV)pacing is the source of ventricular dyssynchrony,leading to unfavorable clinical outcome.T...Background and Objective Cardiac pacing is an effective therapy in patients with bradycardia.Conventional right ventricular(RV)pacing is the source of ventricular dyssynchrony,leading to unfavorable clinical outcome.This study compared the electrocardiogram(ECG)characteristics during left bundle branch pacing(LBBP)with that during RV septal pacing(RVSP)which has been thought to be better than RV apical pacing.展开更多
文摘钠离子电池被广泛研究用于储能应用,但实现同时具有高能量密度、稳定性和快速充放电性能的正极材料仍然是一个关键的挑战。本研究合成了一系列NASICON型Na_(3.5−x)Mn_(0.5)V_(1.5−x)Zrx(PO_(4))_(3)/C材料,并掺入Mn、V和Zr元素探讨其对电化学性能的影响。通过在Mn和V的基础上引入Zr,提出一种激活V4+/V5+氧化还原反应新的策略,从而提升能量密度。此外,Zr掺入通过拓宽离子通道并产生额外的钠离子空位,显著促进钠离子迁移,增强电极反应动力学和整体性能。结果表明,Na_(3.5−x)Mn_(0.5)V_(1.5−x)Zrx(PO_(4))_(3)/C材料表现出优异的循环稳定性,在800次循环后保持90%的容量,并具备高倍率性能(20C时,放电比容量为84 m Ah·g^(-1)),显著优于原始的Na_(3.5−x)Mn_(0.5)V_(1.5−x)Zrx(PO_(4))_(3)/C材料。该研究为开发高效且可持续钠离子电池提供了有效途径。
文摘Objective Reversed U-curve and nonreversed U-curve(conventional technique) were both reported to be effective in treating pulmonary sinus cusp (PSC)-derived ventricular arrhythmia (VA).The aim of this study was to evaluate the characteristics between two methods.
文摘Background and Objective Ablation within the pulmonary sinus of Valsalva (PSV) becomes increasingly common in certain ventricular outflow arrhythmia. Understanding the regional anatomy is intensively concerned to avoid procedure complications. The purpose of this study is to describe the anatomic relationships of PSV to its adjacent structures using computed tomographic coronary angiograms (CTCA).
文摘Background and Objective Cardiac pacing is an effective therapy in patients with bradycardia.Conventional right ventricular(RV)pacing is the source of ventricular dyssynchrony,leading to unfavorable clinical outcome.This study compared the electrocardiogram(ECG)characteristics during left bundle branch pacing(LBBP)with that during RV septal pacing(RVSP)which has been thought to be better than RV apical pacing.
