基于近红外谱形分析的中药提取过程终点判断

中药提取是中药生产的重要环节,其终点的判断直接影响到中药疗效与制药成本.本文提出一种基于近红外光谱谱形分析的典型中药提取过程终点判断方法,该方法为满足工业需求以水的光谱作为近红外参考光谱,根据最小二乘拟合原理去除基线,并且采用滑动窗口相关系数的方法描述谱形差异.实验结果表明：该方法能有效判断中药提取过程终点,方便快速,适合于在线过程分析.     

Electrochromic & magnetic properties of electrode materials for lithium ion batteries

Progress in electrochromic lithium ion batteries(LIBs) is reviewed, highlighting advances and possible research directions. Methods for using the LIB electrode materials' magnetic properties are also described, using several examples.Li_4Ti_5O_(12)(LTO) film is discussed as an electrochromic material and insertion compound. The opto-electrical properties of the LTO film have been characterized by electrical measurements and UV–Vis spectra. A prototype bi-functional electrochromic LIB, incorporating LTO as both electrochromic layer and anode, has also been characterized by charge–discharge measurements and UV–Vis transmittance. The results show that the bi-functional electrochromic LIB prototype works well. Magnetic measurement has proven to be a powerful tool to evaluate the quality of electrode materials. We introduce briefly the magnetism of solids in general, and then discuss the magnetic characteristics of layered oxides, spinel oxides, olivine phosphate Li Fe PO_4, and Nasicon-type Li_3Fe_2(PO_4)_3. We also discuss what kind of impurities can be detected, which will guide us to fabricate high quality films and high performance devices.     

In-situ characterization of electrochromism based on ITO/PEDOT:PSS towards preparation of high performance device

Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)(PEDOT:PSS) is usually sandwiched between indium tin oxide(ITO) and a functional polymer in order to improve the performance of the device. However, because of the strong acidic nature of PEDOT:PSS, the instability of the ITO/PEDOT:PSS interface is also observed. The mechanism of degradation of the device remains is unclear and needs to be further studied. In this article, we investigate the in-situ electrochromism of PEDOT:PSS to disclose the cause of the degradation. X-ray photoelectron spectroscopy(XPS) was used to characterize the PEDOT:PSS films, as well as the PEDOT:PSS plus polyethylene glycol(PEG) films with and without indium ions. The electrochromic devices(ECD) based on PEDOT:PSS and PEG with and without indium ions are carried out by in-situ micro-Raman and laser reflective measurement(LRM). For comparison, ECD based on PEDOT:PSS and PEG films with LiCl, KCl, NaCl or InCl_3 are also investigated by LRM. The results show that PEDOT:PSS is further reduced when negatively biased, and oxidized when positively biased. This could identify that PEDOT:PSS with indium ions from PEDOT:PSS etching ITO will lose dopants when negatively biased. The LRM shows that the device with indium ions has a stronger effect on the reduction property of PEDOT:PSS-PEG film than the device without indium ions. The contrast of the former device is 44%, that of the latter device is about 3%. The LRM also shows that the contrasts of the device based on PEDOT:PSS+PEG with LiCl, KCl, NaCl, InCl_3 are 30%, 27%, 15%, and 18%, respectively.