New, Unexpected Pyranose-Furanose Rearrangement Towards the Synthetic Studies on Rare Sugars and Nucleosides

Preparation of rare aminosugars such as N-acetylgalactosamine （GalNAc） in large quantities is of importance for the chemo-enzymatic synthesis of oligosaccharides. Starting from naturally abundant N-acetylglucosarnine （GIcNAc）, the regio-and stereoselective and new functional group transformation play important roles as the key reactions.     

上海中心城区道路灰尘中氯代多环芳烃的时空分布特征

选取了上海中心城区的道路灰尘作为研究对象, 运用气相色谱-质谱(gas chromatography-mass spectrometry, GC/MS)联用技术对道路灰尘中20种氯代多环芳烃(chlorinated polycyclic aromatic hydrocarbons, ClPAHs)进行了检测, 分析了道路灰尘中ClPAHs的时空分布特征和毒性当量(toxic equivalent quantity, TEQ)等. 结果表明, 11种ClPAHs的检出率均大于50%, 说明ClPAHs在上海中心城区道路灰尘中普遍存在. 研究区域内的ClPAHs浓度呈现出明显的季节特征, 即冬季>夏季, 冬季∑ClPAHs浓度最高为24.9 ng/g干重. 在空间分布上, 交通枢纽区浓度最高(冬季为21.2 ng/g干重, 夏季为10.7 ng/g干重), 建筑施工区、商业区次之, 近绿地区最低. 在道路灰尘中最主要的两个组分是6-ClBaP和7-ClBaA. ClPAHs在冬季和夏季的TEQ范围分别为0.01~4.81和0.01~1.78 ng-TEQ/g干重, 其中 7-ClBaA在ClPAHs总毒性当量中的贡献最大.     

The Jurassic System in SW Japan: review of recent research

The present state of the art in Jurassic oceanicplate stratigraphy in Japan is the result of research over the last two decades. Radiolarian biochronology puts age constraints on the development of fore-arc basin deposits, which cover Permian and Jurassic accretionary complexes of the Outer Zone, facing the Pacific. Special attention is given to the “Torinosu-type” reef-limestone blocks in the Upper Jurassic-Lower Cretaceous fore-arc basin deposits that derived from a shallow-marine continental margin such as the Inner Zone shelf, facing Eurasia. Further progress was achieved in dating and defining sedimentary environments in the Inner Zone Tetori Group. Erosive events during the process of Jurassic accretion are also discussed in relation to the Late Mesozoic geologic and tectonic setting.