Tailoring of extraction solvent of Ixora coccinea flower to enhance charge transport properties in dye-sensitized solar cells

Ionics - We have tailored the extraction solvent of natural anthocyanin pigments from Ixora coccinea flower to lower charge transport resistance and enhance effective electron diffusion coefficient...     

Die Funktionalgleichungen der isomorphen Abbildung

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Eliminationstheorie und allgemeine Idealtheorie

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Gleichungen mit vorgeschriebener Gruppe

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Effects of pure AcOH and mixed AcOH–CS (CS?=?CH3CN and THF) solvents on the rate of cleavage of phthalic anhydride (PAn)

The values of pseudo-first-order rate constants (k _obs) for the acetolysis of phthalic anhydride (PAn) increase from 6.60?×?10^?7 to 31.5?×?10^?7?s^?1 with the increase in temperature from 30 to 50?°C. These values of k _obs give activation parameters ?H* and ?S* as 14.4?±?0.4?kcal?mol^?1 and ?39.1?±?1.3?cal?K^?1?mol^?1, respectively. The values of k _obs remain essentially unchanged with the increase in the content of CS (CS?=?CH₃CN or THF) from 0 to 40?% v/v in mixed AcOH?CCS solvents. These observations have been explained qualitatively.     

Epimeric Mixture Analysis and Absolute Configuration Determination Using an Integrated Spectroscopic and Computational Approach—A Case Study of Two Epimers of 6-Hydroxyhippeastidine

Structural elucidation has always been challenging, and misassignment remains a stringent issue in the field of natural products. The growing interest in discovering unknown, complex natural structures accompanies the increasing awareness concerning misassignments in the community. The combination of various spectroscopic methods with molecular modeling has gained popularity in recent years. In this work, we demonstrated, for the first time, its power to fully elucidate the 2-dimensional and 3-dimensional structures of two epimers in an epimeric mixture of 6-hydroxyhippeastidine. DFT calculation of chemical shifts was first performed to assist the assignment of planar structures. Furthermore, relative and absolute configurations were established by three different ways of computer-assisted structure elucidation (CASE) coupled with ORD/ECD/VCD spectroscopies. In addition, the significant added value of OR/ORD computations to relative and absolute configuration determination was also revealed. Remarkably, the differentiation of two enantiomeric scaffolds (crinine and haemanthamine) was accomplished via OR/ORD calculations with cross-validation by ECD and VCD.     

不变变分问题

本文探讨一类允许(李群意义上的)连续群的变分问题,由此得出的关于所属微分方程的结论会在第一节中作为定理给出一般性表述,在接下来的几节中予以证明。关于由变分问题引发的微分方程会有比关于任意的、允许群变换的微分方程精确得多的论述,后者构成了当前李分析的内容。本文会用到变分的形式计算同李群方法的结合。对于特殊群与变分问题,这样的方法结合并不是什么新鲜事物,这方面此前有Hamel和Herglotz关于特殊有限群的工作,Lorentz和他的学生(例如Fokker),以及Weyl 和 Klein关于特殊无限群的工作。特别地,克莱因的第二篇论文同本文相互影响,关于这一点我提请关注克莱因文章的结论部分。     

Nichtkommutative Algebra

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