Anionic surfactant selective electrode for the titrimetric determination of anionic surfactant

The construction and characteristic performance of a PVC membrane electrode responsive for sodium dodecylsulfate (SDS) are described in this paper. The electrode based on CTA⁺DS^? ion pair as ionophore in PVC membrane displays a Nernstian slope of ?58.8 ± 0.7 mV/decade in a 1.32 × 10^?6 to 3.75 × 10^?3 mol L^?1 concentration range and a limit of detection of 1.13 × 10^?6 mol L^?1. The electrode can be used for 3 months without showing significant changes in the value of slope or working range. The electrode has been utilized as an end point indicator electrode for potentiometric titration involving Hyamine as titrant. More than 100 titrations were carried out for the evaluation of the electrode parameters: the standard deviations of the equivalent volume and the equivalent potential, the height of the potential jump and the number of faulty titrations. The behavior of the electrode was assessed with regard to their usefulness in routine analysis.     

Polypropylene/poly(butyl methacrylate) blends prepared by diffusion and subsequent polymerization of butyl methacrylate in isotactic polypropylene pellets

Polypropylene/poly(butyl methacrylate)(PP/PBMA) blends were prepared by diffusion and subsequent polymerization of butyl methacrylate(BMA) in commercial isotactic polypropylene(iPP) pellets.The diffusion kinetics,diametrical distribution of PBMA in a pellet and phase morphology of a typical PP/PBMA blend were investigated.     

UPLC-ELSD Determination of 1-Octacosanol in Raw Material and Health Products

Determination of the levels of 1-octacosanol is important in food stuff for the study of its pharmacological activities and health benefits. In this study, a novel, simple and fast internal standard method for the non-derivatization ultra-performance liquid chromatographic determination of 1-octacosanol in raw materials and health products was developed and validated based on evaporative light scattering detection. The linearity (r ² > 0.998), recovery (99.1–100.2%, RSD <2.7%), intra- and inter-day precision (RSD <3.8%), limit of detection (1.0 mg/L), limit of quantification (2.2 mg/L) of the 1-octacosanol were determined. The method was successfully applied to nine real 1-octacosanol products. The results of analyses had close agreement with the labeled claims of 1-octacosanol content in these products. Compared with the classical gas chromatography method, the developed method was simpler, faster and more environmentally friendly due to avoiding any derivatization step. This protocol represents a rapid and feasible method for quality control of 1-octacosanol products.

     

5,15-二（二茂铁基）-卟啉酞菁钇的结构和振动光谱的密度泛函理论研究

本文选用混杂的B3LYP密度泛函理论方法,在Lanl2dz水平上,对5,15-二（二茂铁基）-卟啉酞菁钇[Por(Fc)2]Y(Pc)的结构进行了优化,结果表明,5,15-二（二茂铁基）-卟啉酞菁钇呈现出三明治型构型,卟啉环与酞菁环呈穹型围绕在金属钇原子周围。对分子内主要的键长与键角进行了理论计算,通过频率计算,得到了5,15-二（二茂铁基）-卟啉酞菁钇[Por(Fc)2]Y(Pc)的红外光谱图,与实验所得的红外光谱图进行比对,将理论计算和实验所得的光谱主要振动峰进行了线性回归拟合,相关系数为0.992,标准偏差为16.96。理论计算与实验所获得的红外光谱图基本一致,说明本文所选用的DFT理论计算方法是可行的。通过GaussView软件对5,15-二（二茂铁基）-卟啉酞菁钇的红外谱带简正振动模式进行了指认。此外,分析讨论了5,15-二（二茂铁基）-卟啉酞菁钇[Por(Fc)2]Y(Pc)的分子静电势,确定了极大值与极小值的位置。对于研究5,15-二（二茂铁基）-卟啉酞菁钇分子的性质,提供了相应的理论基础。     

Global optimization design of quasi-optics fower combiner of solid-state millimeter wave resonator

This paper describes a global optimization design of quasi-optics power combiner of solid-state millimeterwave resonator. It is operated in the frequency range from 50 to 300 GHz using GaAs Gunn diodes. It is shown that sourcearrays containing N² (N=3,5,...2K+1, where k is positive integer) individual elements. It is very efficient power transfer of energy from the source-array to the fractional power of the fundamental beam mode etc.. The RF output power exceeded the sum of the individual diodes to be threefold to sevenfold. And this data is the global optimization solution.     

A global optimization design for quasi-optics power combiner of 3mm wave solid-state sources

This paper describes a global optimization design for quasi-optics power combiner of solid-state millimeter-wave sources. The operating frequency is about 100 GHz and the oscillating sources are GaAs Gunn diodes. The source-array plane is a matrix consisting of NxN (N=3,5, ..., 2k+1, where k is positive integer) diodes. The radio frequency power of the combiner is from threefold to sevenfold larger than the sum total of the single diodes power. The global optimums of the array and the location in the cuvity of the suorce-array plane will be given by a global optimizition method.     

利用KTP晶体实现1.08μmNd：YAP激光器锁模

本文描述了利用ＫＴＰ晶体和腔的基波输出镜构成非线性镜实现１．０８μｍＮｄ：ＹＡＰ激光器的被动锁模。实验表明，这种新的锁模技术比用染料作可饱和吸收体的被动锁模技术有很多突出的优点，具有很大的发展潜力。实验测得锁模时基波１．０８μｍ输出２．４ｍＪ，二次谐波０．５４μｍ输出０．５ｍＪ（同样条件下的静态输出为２．５ｍＪ），基波脉冲的平均脉宽为４０ｐｓ。