不同岩蔷薇浸膏挥发性致香成分的SED-GC-MS分析研究

岩蔷薇(cistusladaniferusL.)又名赖百当(labdanum),属半日花科。利用其树脂分泌物及枝叶,通过蒸馏、浸提和萃取等方法,可制得岩蔷薇精油、浸膏、净油、油树脂等各种香原料品种。岩蔷薇的香原料制品是膏香类的极重要品种,主要应用于日化和食品行业,在烟草行业也多有应用。因香料烟香味的主要来源是类赖百当化合物的降解,故被归为烟草的五大类香味物质之一:赖百当类、双萜烯及其降解产物类。这类物质在香料烟中的含量较高,对形成香料烟的特殊香味风格具有重要意义,且在烟草中赖百当仅存在于香料烟中,烤烟、自肋烟中均不存在。赖百当类化合物是香料烟中特有的香气物质,主要成分是冷杉醇、赖百当烯二醇,经调制和醇化转化为多种降赖百当类化合物,其中降龙涎香醚、龙涎香内酯、脱氢龙涎香内酯等都具有强烈的龙涎香香气,对增进卷烟香气和吃味有很好作用。     

Quantitative Spektralanalyse

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Qualitative und quantitative Spektralanalyse

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Literatur

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Observation of quantum coherence in mesoscopic molecular magnets

By applying a transverse magnetic field B( perpendicular) of sufficient strength to the uniaxial molecular magnets Fe8 and Mn12, the tunneling splitting Delta(t) of their S = +/-10 magnetic ground states can be made large compared to perturbations such as hyperfine and dipolar interactions. We present evidence for such a Delta(t) from magnetic specific heat data below 1 K that is consistent with coherent quantum mechanical tunneling in a "mesoscopic" system under such conditions.     

Catalytic hyperbranched polymers as enzyme mimics; exploiting the principles of encapsulation and supramolecular chemistry

Nature uses the principles of encapsulation and supramolecular chemistry to bind and orientate substrates within active catalytic sites. Over the years, synthetic chemistry has generated a number of small molecule active site mimics capable of catalysing reactions involving bound substrates. Another approach uses larger molecules that better represent an enzymes globular structure. These molecules mimic an enzymes structure by incorporating binding/catalytic sites within the globular structure of the polymer. As such, the electronic and steric properties around the binding/catalytic site(s) can be controlled and fine-tuned. One class of polymer that is particularly adept at mimicking the globular structure of enzymes are dendritic polymers. This review will concentrate on the use of hyperbranched polymers as synthetic enzyme mimics.     

Pyridine encapsulated hyperbranched polymers as mimetic models of haeme containing proteins, that also provide interesting and unusual porphyrin-ligand geometries

This communication describes the use of non-covalent chemistry to construct recyclable porphyrin cored HBPs. The non-covalent design allows the polymeric backbone to be rescued and reused after porphyrin degradation. The steric environment within the polymeric encapsulated ligand notably affected the porphyrin coordination geometry.     

Porphyrin cored hyperbranched polymers as heme protein models

The single step synthesis of an Fe(II) porphyrin cored hyperbranched polymer, possessing similar size and topology to the natural heme containing proteins, is reported: UV spectroscopy successfully demonstrated the ability of this polymer to reversibly bind oxygen.