Organic electrodes are advantageous for rechargeable lithium-ion batteries owing to their high theoretical capacities, diverse functionalities, and environmental compatibility. Understanding the working mechanism of o...Organic electrodes are advantageous for rechargeable lithium-ion batteries owing to their high theoretical capacities, diverse functionalities, and environmental compatibility. Understanding the working mechanism of organic electrodes is vital to strategic materials design. However, due to lack of suitable characterization tools, it has been challenging to probe the reaction processes of organic electrodes in real-time. Here, non-destructive in situ electron paramagnetic resonance(EPR) was performed on a model organic electrode, 7,7,8,8-tetracyanoquinodimethane(TCNQ) used in rechargeable lithium-ion batteries,to directly follow the redox reactions in real-time. In order to minimize interfering signals from other parts of the batteries than the TCNQ electrode of interest, two sets of batteries are fabricated and studied with in situ EPR:(1) a Li CoO_(2)//Li_(4)Ti_5O_(12) full-cell battery to determine the EPR signal evolution of additives and electrolytes;(2) a Li CoO_(2)//TCNQ battery, and the difference in the observed EPR signals reflects purely the redox reactions of TCNQ upon lithiation and delithiation. A two-electron reversible redox reaction is delineated for TCNQ. TCNQ dimers form during the first electron injection upon lithiation and followed by the break-down of the dimers and associated electron coupling to produce massive delocalized electrons, resulting in increased EPR signal during the 2 nd electron injection. Reversible trends are observed during electron ejection upon delithiation. In situ EPR is very sensitive to electron activities,thus is a powerful tool to follow redox reactions of organic electrodes, allowing for improved fundamental understanding of how organic electrodes work and for informed design of high-performance organic materials for energy storage.展开更多
[目的]探讨鸡热休克蛋白8(heat shock protein family A member 8,HSPA8)的生物学特性及其在应激状态下胸腺中的表达模式。[方法]试验以固始鸡胸腺为材料,利用PCR技术扩增并克隆HSPA8基因CDS区,通过生物信息学方法分析其生物学特性和结...[目的]探讨鸡热休克蛋白8(heat shock protein family A member 8,HSPA8)的生物学特性及其在应激状态下胸腺中的表达模式。[方法]试验以固始鸡胸腺为材料,利用PCR技术扩增并克隆HSPA8基因CDS区,通过生物信息学方法分析其生物学特性和结构特点,并检测其在不同组织中的相对表达量。构建断喙应激和热应激模型,采用实时荧光定量PCR技术检测炎症因子和HSPA8基因在不同应激模型鸡胸腺中的表达情况。[结果]鸡HSPA8基因CDS区长度为1 941 bp,共编码氨基酸646个,与红原鸡基因序列相似性为98.92%;HSPA8基因核苷酸序列的系统发育树结果表明,固始鸡与火鸡亲缘关系最近,与哺乳动物次之,与低等鱼类亲缘关系最远;HSPA8蛋白属于酸性蛋白,稳定性和亲水性强,不属于分泌蛋白且无跨膜结构域,有多个磷酸化和糖基化修饰位点,主要在细胞核内发挥作用,具有2个保守性结构域,与DNAJC5、HSPB1、DNAJA1和GAK等蛋白存在相互作用;HSAP8基因在雏鸡各组织中广泛表达,其中在胰腺中表达量最高,在胸肌中表达量最低;应激模型评价结果发现,断喙应激和热应激导致鸡血清皮质酮、白细胞介素-6(IL-6)和肿瘤坏死因子-α(TNF-α)等含量显著增加(P<0.05),T细胞亚群(CD3^(+))和免疫球蛋白G(IgG)含量有所降低;断喙应激模型鸡胸腺中IL-1β、IL-6、TNF-α和IL-8基因表达量在第1天显著升高(P<0.05),第5天显著降低(P<0.05);热应激模型鸡胸腺中IL-1β、IL-6、TNF-α和IL-8基因表达量显著升高(P<0.05);HSPA8基因在断喙后第1和3天胸腺中表达量显著升高(P<0.05),第5天显著降低(P<0.05);在持续热应激组中显著降低(P<0.05)。[结论]HSPA8基因参与鸡胸腺应激性免疫应答反应,可作为反映家禽是否处于应激性免疫抑制状态的可靠指标。以上结果为进一步研究HSPA8的免疫调控功能提供参考依据。展开更多
基金supported by the National Science Foundation under Grant No. DMR-1847038supported by the National Science Foundation Cooperative Agreement No. DMR-1644779 and the State of Florida。
文摘Organic electrodes are advantageous for rechargeable lithium-ion batteries owing to their high theoretical capacities, diverse functionalities, and environmental compatibility. Understanding the working mechanism of organic electrodes is vital to strategic materials design. However, due to lack of suitable characterization tools, it has been challenging to probe the reaction processes of organic electrodes in real-time. Here, non-destructive in situ electron paramagnetic resonance(EPR) was performed on a model organic electrode, 7,7,8,8-tetracyanoquinodimethane(TCNQ) used in rechargeable lithium-ion batteries,to directly follow the redox reactions in real-time. In order to minimize interfering signals from other parts of the batteries than the TCNQ electrode of interest, two sets of batteries are fabricated and studied with in situ EPR:(1) a Li CoO_(2)//Li_(4)Ti_5O_(12) full-cell battery to determine the EPR signal evolution of additives and electrolytes;(2) a Li CoO_(2)//TCNQ battery, and the difference in the observed EPR signals reflects purely the redox reactions of TCNQ upon lithiation and delithiation. A two-electron reversible redox reaction is delineated for TCNQ. TCNQ dimers form during the first electron injection upon lithiation and followed by the break-down of the dimers and associated electron coupling to produce massive delocalized electrons, resulting in increased EPR signal during the 2 nd electron injection. Reversible trends are observed during electron ejection upon delithiation. In situ EPR is very sensitive to electron activities,thus is a powerful tool to follow redox reactions of organic electrodes, allowing for improved fundamental understanding of how organic electrodes work and for informed design of high-performance organic materials for energy storage.
文摘[目的]探讨鸡热休克蛋白8(heat shock protein family A member 8,HSPA8)的生物学特性及其在应激状态下胸腺中的表达模式。[方法]试验以固始鸡胸腺为材料,利用PCR技术扩增并克隆HSPA8基因CDS区,通过生物信息学方法分析其生物学特性和结构特点,并检测其在不同组织中的相对表达量。构建断喙应激和热应激模型,采用实时荧光定量PCR技术检测炎症因子和HSPA8基因在不同应激模型鸡胸腺中的表达情况。[结果]鸡HSPA8基因CDS区长度为1 941 bp,共编码氨基酸646个,与红原鸡基因序列相似性为98.92%;HSPA8基因核苷酸序列的系统发育树结果表明,固始鸡与火鸡亲缘关系最近,与哺乳动物次之,与低等鱼类亲缘关系最远;HSPA8蛋白属于酸性蛋白,稳定性和亲水性强,不属于分泌蛋白且无跨膜结构域,有多个磷酸化和糖基化修饰位点,主要在细胞核内发挥作用,具有2个保守性结构域,与DNAJC5、HSPB1、DNAJA1和GAK等蛋白存在相互作用;HSAP8基因在雏鸡各组织中广泛表达,其中在胰腺中表达量最高,在胸肌中表达量最低;应激模型评价结果发现,断喙应激和热应激导致鸡血清皮质酮、白细胞介素-6(IL-6)和肿瘤坏死因子-α(TNF-α)等含量显著增加(P<0.05),T细胞亚群(CD3^(+))和免疫球蛋白G(IgG)含量有所降低;断喙应激模型鸡胸腺中IL-1β、IL-6、TNF-α和IL-8基因表达量在第1天显著升高(P<0.05),第5天显著降低(P<0.05);热应激模型鸡胸腺中IL-1β、IL-6、TNF-α和IL-8基因表达量显著升高(P<0.05);HSPA8基因在断喙后第1和3天胸腺中表达量显著升高(P<0.05),第5天显著降低(P<0.05);在持续热应激组中显著降低(P<0.05)。[结论]HSPA8基因参与鸡胸腺应激性免疫应答反应,可作为反映家禽是否处于应激性免疫抑制状态的可靠指标。以上结果为进一步研究HSPA8的免疫调控功能提供参考依据。
