A New Triterpene from the Orchid Pholidota yunnanensis

A new triterpene, 25-methylenecyclopholidonyl p-hydroxy-trans-cinnamate, was isolated from a orchid Pholidota yunnanensis. The structure elucidation and ^1H, ^13C-NMR assignments were achieved by spectral and chemical method.     

Formation of α,α''''-Bis(substituted benzylidene)cycloalkanones from Masked Aldehydes Promoted by Samarium(III) Triiodide

~~Formation of α,α'-Bis(substituted benzylidene)cycloalkanones from Masked Aldehydes Promoted by Samarium(III) Triiodide~~     

Synthesis and Photochemical Properties of a New Substituted Phenol Covalently Linked to Ruthenium （Ⅱ） Tris-bipyridine Containing Four Ester Groups as Sensitizer

As photosensitizer for solar cell, a new ruthenium (Ⅱ) complex with four ester groups had been synthesized, in which a phenol substituted by {[(2-hydroxy-5-tert-butylbenzyl)(pyridyl-2-methyl)amino]methyl} is covalently linked to ruthenium (Ⅱ) tris-bipyridine. The structures of the new compounds were confirmed by NMR and ESI-MS spectra. The electrochemical and photochemical properties were also studied.     

Solid Phase Synthesis of 2-Substituted 1,3-Oxazin-6-ones Using Resin-bound Cyclic Malonic Acid Ester

A facile solid phase synthesis of 2-substituted 1,3-oxazin-6-ones using polymer-supported Meldrum‘s acid has been reported. Reaction of the resin-bound cyclic malonic acid ester with triethyl orthoformate and subsequent double substitution with amide, afforded the corresponding polymer-supported acylaminomethylene cyclic malonic acid ester, which upon thermal treatment led to 1, 3-oxazin-6-ones in good yields and with high purity.     

Microwave-promoted Palladium Catalyzed Suzuki Cross-coupling Reaction in WaterI

A simple, rapid and environmental friendly method for the synthesis of biaryl compounds under microwave irradiation is reported.     

The First and Facile Synthesis of (±) Syringaresinol

The first and facile synthesis of (±)syringaresinol was described.     

6p2阶的三度半对称图

正则图G 称为G-半对称图, 如果G 的自同构群A := AutG 有一个子群G在G 的边集上传递, 但在其点集上不传递, 特别地, 当G= A时Γ 称为半对称图. 本文旨在考察素数度的(G-)半对称图. 首先给出了素度数的(G-)半对称图的群论刻画, 其次对6p²阶的三度半对称图进行了完全分类, 其中p是奇素数.     

Nd~(3+):YAG激光的光纤传输

首先叙述了光纤传输Nd~(3+): YAG激光的优点,接着分析了不同光纤和其传输Nd~(3+): YAG激光的特点。然后通过对光纤传输系统各部分的分析与设计,结合实际,设计了光纤耦合机构。最后,对来自于工件反射光问题提出了解决方案。     

混合稀土EuBaCuO体系的高温超导电性研究

本报道了采用三种不同含量的混合稀土Ｅｕ２Ｏ３（Ｅｕ２Ｏ３的含量分别为７０％，７９．９８％，９０％）为原料，利用固态反应法制备混合稀土Ｅｕ－Ｂａ－Ｃｕ－Ｏ体系超导体样品的工艺；给出了高温超导电性测量和Ｘ射线粉末衍射及扫描电镜分析结果。