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~~     

The First Intramolecular Charge Transfer Transition Based on 2-Ureido-4[1H]-pyrimidinone Binding Module

The first intramolecular charge transfer transition based on 2-ureido-4[1H]-pyrimidinone binding module was reported.     

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.     

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.     

二极管泵浦1064nm单频Nd:YVO4激光器的研究

报道了一种用国产激光二极管泵浦的1064nm单频NdYVO4红外激光器的设计.利用布氏片和石英晶体组合构成的双折射滤光片技术,在泵浦功率为800mW时,实现了功率为360mW的1064nm红外单频输出.测量结果表明,偏振比超过了10001,功率稳定性优于0.5%,振幅噪声小于0.1%.     

铬（Ⅵ）—DBC—HNO3催化动力学光度法测定痕量铬（Ⅵ）

在硝酸介质中，痕量铬(Ⅵ)能灵敏的催化氧化DBC褪色。研究了反应的最佳条件，建立了测定痕量铬(Ⅵ)的新方法。检出限可达10^-9g／ml，测定范围为0．12--0．7μgCrC(Ⅵ)／10ml，方法简便、灵敏、快速、准确。用于测定水中的痕量铬(Ⅵ)，获得了满意的结果。     

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。     

Spectra Analysis of a Novel Ti-Doped LiAlO2 Single Crystal

LiAlO2 single crvstals doped with Ti at concentration 0.2at.% are grown by the Czochralskl technique with dimensions φ42×55mm. Ti ions in the crystal are quadrivalence proven by comparing the absorption and fluorescence spectra of pure LiAlO2 and Ti： LiAlO2. After air and Li-rich atmosphere annealing, the absorption peaks in the range of 600-800nm disappear. We conclude that 682 and 756nm absorption peaks are attributed to the VLi and Vo absorptions, respectively： The peaks at 716nm and 798nm may stem from the VLi^＋ and absorptions. The colour-centre model can be applied to explain the experimental phenomena. Ti^4＋-doping produces more lithium vacancies in the LiAlO2 crystal. The intensities of [LiO4] and the associated bonds remain unchanged, which improves the anti-hydrolyzation and thermal stability of LiAlO2 crystals.