107 research outputs found
骨肉瘤细胞外泌体激活肺组织成纤维细胞炎性信号通路
目的本研究旨在研究骨肉瘤细胞来源外泌体对靶器官微环境的调控作用及其分子机制。方法提取骨肉瘤细胞143B外泌体并鉴定,通过PKH26荧光染色后经尾静脉注入裸鼠体内,24 h后提取肝、脾、肺、肾及脑组织,荧光显微镜下计数不同视野红色荧光数量;通过免疫荧光检测不同类型细胞中外泌体摄取情况;143B外泌体与人肺成纤维细胞共培养,荧光显微镜检测摄取情况,进一步利用qPCR检测炎性因子IL-1β、IL-6及TNF-α表达水平,通过蛋白印迹法检测炎性信号通路NF-κB通路p-p65和MAPK通路p-ERK及p-p38的变化。结果143B细胞外泌体中TSG101、Flotillin-1、CD63、CD9表达,Calnexin表达缺失(P<0.05);电镜外泌体呈“茶托”样形状,大小为(141.92±52.85) nm;外泌体经裸鼠尾静脉注射后进入肺组织含量显著高于肝、肾、脾、脑等器官(P<0.05);外泌体与人肺成纤维细胞共培养后炎性因子IL-1β、IL-6及TNF-α mRNA水平明显升高(P<0.05),同时p-p65,p-ERK及p-p38均显著上调(P<0.05)。结论骨肉瘤细胞外泌体可激活肺成纤维细胞NF-κB及MAPK炎性信号通路,进而促进炎性因子IL-1β、IL-6及TNF-α产生
有机添加剂对超级电容器界面特性及能量密度的影响
能量密度较低是双电层超级电容器急需突破的瓶颈问题之一,材料/电解液的表界面作为离子吸附以及储存能量的场所,其特性对超级电容器的比电容具有重要影响。本文通过向离子液体和水系电解液中加入不同的有机添加剂,研究有机添加剂对固-液表界面润湿性以及界面离子浓度分布等的影响,揭示了有机添加剂对超级电容器比电容和能量密度的影响及机制。取得主要结论如下:(1)针对离子液体电解液黏度高、润湿性差的问题,采用添加乙腈来提高表界面的润湿性。结果表明当离子液体[EMIM]BF4与乙腈的体积比达到1:3时,界面的接触角从43°降低到15°,润湿性的大幅提高导致材料的比表面积利用率增加,材料的比电容从12.1 F/cm3增加到29.4 F/cm3。 (2)在水系电解液中,研究了异丙醇对超级电容器比电容和能量密度的影响。发现异丙醇的加入不仅可以提高活性炭界面的润湿性,同时还有效的提高了体系在长循环后的比电容保持率;20vol%的异丙醇可以明显抑制体系在高电势下的极化现象,将工作电压窗口从-0.8~0 V提高到-0.8~0.5 V,超级电容器的能量密度也从纯水体系中的7.0 Wh/kg增加到了19.4 Wh/kg;活性炭在高电流密度(10 A/g)下比电容的衰减幅度也因为异丙醇的加入得到了巨大改善,从30.3%降低到13.9%。(3)采用实验与模拟相结合的方法,揭示了电极表面离子分布对超级电容器比电容的影响及其动力学调控机制。首先研究了电解质浓度对比电容的影响,DFT模拟发现高浓度电解质导致电极表面离子呈现多层有序分布,导致比电容的升高。通过添加有机添加剂甘油来改变离子的传递速率和充电速率,发现了动力学过程对表面离子分布的影响,提出高能量密度的离子吸附模型及其动力学优化路径。;Low energy density is one of the bottleneck problems hindering the development of double layer supercapacitors. The interface of materials and electrolytes serves as the place for ion adsorption and energy storage, which has a great influence on the specific capacitance of supercapacitors. In this paper, by adding different organic solvents into the ionic liquid and the aqueous electrolyte, the effects of organic additives on the interfacial wettability and the ion concentration distribution at interface of electrode were investigated respectively. The interface characteristics were associated with the specific capacitance and energy density of supercapacitors. The main conclusions are shown in the followings:(1)High viscosity and poor wettability are the main problems of ionic liquid as the electrolyte of supercapacitors. The acetonitrile was selected in this study and added into ionic liquid [EMIM]BF4 to improve the wettability. It was showed that when the volume ratio of [EMIM]BF4 and acetonitrile was 1:3, the contact angle of interface decreased from 43° to 15°, which resulted in a good wettability and a high utilization rate of specific surface area. The specific capacitance of materials increased from 12.1 F/cm3 to 29.4 F/cm3 as a result of the addition of acetonitrile(2)The effect of isopropanol on the specific capacitance and energy density of aqueous electrolyte was investigated in this study. It was found that the addition of isopropanol not only enhanced the wettability of the interface, but also improved the specific capacitance retention after long-term cycles effectively. In addition, 20vol% addition of isopropanol inhibited the polarization at high potential significantly, which increased the voltage window from -0.8~0 V to -0.8~0.5 V, leading to the energy density improved from 7.0 Wh/kg in 6 M KOH to 19.4 Wh/kg. The specific capacitance attenuation at high current density (10 A/g) was also improved greatly by the addition of isopropanol, which dropped from 30.3% to 13.9%.(3)By the experiments and simulations, the influence of ion distribution in the surface of electrode on the specific capacitance and its kinetic regulation mechanism was revealed. Firstly, the effect of aqueous electrolyte concentration on the specific capacitance was investigated. The DFT simulation revealed that there was multi-layered orderly packing of ions at the interface of electrode at the high concentration of electrolyte, which resulted in a high specific capacitance. By regulating the transport rate of ions in electrolyte and the charging rate of ions, the influence of kinetics process on the specific capacitance was investigated. A model with multi-layered adsorption of ions was proposed for a high capacitance , and the kinetic in favor of multi-layered adsorption was pointed out. </p
Talent Introduction Model and Strategy Analysis of Rural Enterprises Based on Tripartite Game
The Localization of NEK6 in HepG2 Cell Line and Its Expression and Clinical Significance in HCC
基于改进阶次分析与自适应VMD的变转速齿轮箱故障诊断研究
变转速齿轮箱由于工况复杂导致转频不稳定,齿轮箱的微弱故障信号可能会被掩盖在强噪声中,不能直接应用传统的时频分析方法,为故障特征的提取增加一定的难度。针对变转速信号的处理,传统的计算阶次分析方式(COT)很好地解决了变转速齿轮箱的故障特征难以提取出来的问题,但由于传统COT中所使用的重采样方法是基于样条插值法的,无法根据转频选取转频,导致重采样间隔并不均匀;提出了改进的阶次分析方法,根据采样的各点角速度依次进行重采样,提高了阶次分析的精度。同时,变转速齿轮箱因动力传递复杂,导致变转速齿轮箱噪声更加严重。变分模态分解(VMD)常被被用来去除复杂信号噪声,提取被掩盖在强噪声中的微弱故障信号。提出了自适应VMD使用能量法,确定分解层数后对分量进行指标化选取,使去噪的效果得到进一步提升。通过对实验信号分析,使用此方法进行验证。结果表明,此方法能有效转换变转速齿轮箱信号为阶次信号并对故障进行识别
有机添加剂对超级电容器中水系电解液理化性能的影响
以6 mol/L KOH水溶液为电解液,高比表面积的活性炭为活性物质,研究了有机添加剂对体系润湿性、电导率、工作电压窗口及阻抗的影响,测试了超级电容器的电化学性能。结果表明,适量添加有机添加剂可明显抑制体系的极化现象,提高超级电容器的工作电压窗口。添加10vol%异丙醇时,电极材料和电解液间的润湿性大幅提高,比电容从79.3 F/g提高至113.2F/g。添加20vol%异丙醇时,超级电容器的能量密度达19.4Wh/kg,体系的电荷转移电阻明显降低,在10A/g电流密度下的比电容比0.5 A/g时下降13.9%,而不加添加剂时下降30.3%。添加30vol%异丙醇时,电解液电导率迅速下降,比电容降低,电导率是影响比电容的关键因素
有机添加剂对超级电容器中水系电解液理化性能的影响
以6 mol/L KOH水溶液为电解液,高比表面积的活性炭为活性物质,研究了有机添加剂对体系润湿性、电导率、工作电压窗口及阻抗的影响,测试了超级电容器的电化学性能。结果表明,适量添加有机添加剂可明显抑制体系的极化现象,提高超级电容器的工作电压窗口。添加10vol%异丙醇时,电极材料和电解液间的润湿性大幅提高,比电容从79.3 F/g提高至113.2 F/g。添加20vol%异丙醇时,超级电容器的能量密度达19.4 Wh/kg,体系的电荷转移电阻明显降低,在10 A/g电流密度下的比电容比0.5 A/g时下降13.9%,而不加添加剂时下降30.3%。添加30vol%异丙醇时,电解液电导率迅速下降,比电容降低,电导率是影响比电容的关键因素
有机添加剂对超级电容器中水系电解液理化性能的影响
以6 mol/L KOH水溶液为电解液,高比表面积的活性炭为活性物质,研究了有机添加剂对体系润湿性、电导率、工作电压窗口及阻抗的影响,测试了超级电容器的电化学性能。结果表明,适量添加有机添加剂可明显抑制体系的极化现象,提高超级电容器的工作电压窗口。添加10vol%异丙醇时,电极材料和电解液间的润湿性大幅提高,比电容从79.3 F/g提高至113.2 F/g。添加20vol%异丙醇时,超级电容器的能量密度达19.4 Wh/kg,体系的电荷转移电阻明显降低,在10 A/g电流密度下的比电容比0.5 A/g时下降13.9%,而不加添加剂时下降30.3%。添加30vol%异丙醇时,电解液电导率迅速下降,比电容降低,电导率是影响比电容的关键因素
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