基于UPLC-Orbitrap-HRMS技术的苎麻籽乙醇提取物中主要化学成分分析与鉴定

应用超高效液相色谱-离子阱-超高分辨率质谱技术对苎麻籽乙醇提取物主要化学成分进行了分析与鉴定.高效液相色谱条件为Agilent 5TC-C18色谱柱(4.6 mm×250 mm,5μm)、0.2％甲酸水溶液-乙腈作为流动相梯度洗脱.质谱条件为电喷雾离子源(ESI),离子阱质量分析器(orbitrap),喷雾电压3500...     

超高强混凝土用低水胶比浆体的水化热研究

采用自行改进的水化热测定系统,研究了粉煤灰、矿渣粉和水胶比对超高强混凝土用低水胶比浆体水化热和水化进程的影响规律.结果表明:掺10%(质量分数,下同)粉煤灰或矿渣粉不影响低水胶比浆体的水化进程;掺30%,50%粉煤灰或矿渣粉均使低水胶比浆体的水化温升和水化放热速率峰值明显降低,并延缓这些峰值出现的时间,且粉煤灰对水化进程的延缓效果优于同等掺量的矿渣粉;提高水胶比只能略微推迟浆体的水化温升和水化放热速率峰值出现的时间,使水化放热速率峰值有所增大,不会改变浆体温升曲线和放热速率曲线的形状.     

深圳大铲湾港区温馨港湾结构设计及计算分析

以接近超限的深圳大铲湾港区温馨港湾结构为工程实例,利用PKPM和MIDAS进行了弹性及弹塑性有限元对比分析,并分析了结构非线性发展的过程,结果说明该结构的布置是合理的,结构是安全可靠的。     

超超临界直流炉无炉水循环泵稳压吹管

对锅炉启动系统设计有炉水泵的660 MW超超临界机组进行了无炉水泵吹管的可行性分析,确定了采用无炉水循环泵吹管的方案。介绍了吹管系统的设计和吹管参数的选择,选择稳压吹管的方式,提出无炉水循环泵稳压吹管的技术要点。实践证明,通过利用给水泵和给水旁路调节阀控制给水流量,并尽早投入化学精处理系统以回收分离器疏水,完全可以较好实现设计有炉水泵机组的无炉水泵启动稳压吹管。     

特低渗透油藏裂缝分布规律研究

分析了特低渗透油藏裂缝研究存在的问题、目前的研究现状和发展趋势,分析并总结了渗透油藏裂缝研究的基本思路。认为特低渗透油藏裂缝研究理论应用前景广阔。     

A review of the features and analyses of the solid electrolyte interphase in Li-ion batteries

The solid electrolyte interphase (SEI) is a protecting layer formed on the negative electrode of Li-ion batteries as a result of electrolyte decomposition, mainly during the first cycle. Battery performance, irreversible charge “loss”, rate capability, cyclability, exfoliation of graphite and safety are highly dependent on the quality of the SEI. Therefore, understanding the actual nature and composition of SEI is of prime interest. If the chemistry of the SEI formation and the manner in which each component affects battery performance are understood, SEI could be tuned to improve battery performance. In this paper key points related to the nature, formation, and features of the SEI formed on carbon negative electrodes are discussed. SEI has been analyzed by various analytical techniques amongst which FTIR and XPS are most widely used. FTIR and XPS data of SEI and its components as published by many research groups are compiled in tables for getting a global picture of what is known about the SEI. This article shall serve as a handy reference as well as a starting point for research related to SEI.     

Elaboration of Ultra‐High Molecular Weight Polyethylene/Carbon Nanotubes Electrospun Composite Fibers

Micron‐sized fibers of UHMWPE reinforced with CNT were fabricated by the electrospinning process. Conditions for a metastable mutual solution of UHMWPE and CNTs were found at elevated temperature. These solutions were used for electrospining using a device having controlled temperature and gaseous environment around the electrospun liquid jet. The fabricated micron‐sized fibers exhibited the reinforcing CNTs as self‐organized nano‐ropes embedded within them. A post‐spinning drawing process enhanced the mechanical properties of the composite fibers to the level of 6.6 GPa strength and elongation at break of 6%. The CNT nano‐ropes form spontaneously in the liquid jet during electrospinning, and provide the reinforcement framework which is amenable for post‐drawing of the fibers for subsequent utilization as composite nanofibers. The experimental results exhibit the highest strength value reported to date for electrospun fibers.

     

膜分离技术在电厂锅炉补给水中的应用

介绍了膜分离技术如超滤、反渗透、电除盐的原理及在电厂中的使用情况,并以大同某电厂为例介绍了最新的全膜分离工艺在实际中的应用效果。指出膜技术在使用过程中不用酸碱再生,避免了传统的离子交换技术有大量的酸碱废液排放,是今后电厂水处理的方向。     

特高压线路参数对线路谐波传递系数的影响

选用均匀传输线路为特高压线路模型,推导了谐波传递系数的公式,对以分布参数表示的线路模型和以集中参数表示的线路模型进行了比较分析,研究了不同线路参数对谐波传递系数变化规律的影响,同时给出了线路终端负载变化对谐波传递系数的影响趋势图。     

1000 kV特高压变压器现场绕组变形测量与分析

以国内首台1 000 kV特高压变压器现场绕组变形测量试验为例,介绍了采用频率响应法(FRA)和短路阻抗法(SCR)对特高压变压器绕组变形进行综合判断的情况,详细说明了2种方法的特点、现场试验技术和测量结果,有效提高了变压器绕组变形诊断的可靠性和准确性。