Quantum State Transfer between Two Distant Atoms by Connecting Two Cavities via Optical Fibres

A scheme is proposed to unconditionally implement state transfer between two distant atoms by sending the atoms across two distant cavities connected via an optical fibre, respectively. The field state, which preserves the information about the first atom, is transmitted from one cavity to the other along the fibre. A Faraday rotator integrated in the fibre can be designed to completely stop the fields reflected from the second cavity, thus after the field interacts with the second atom for a defined time, the state transfer can be accomplished with unit efficiency.     

天然产物海洋联烯Xyloallenoid F的全合成

以丙炔醇为原料, 经Mannich反应、还原、溴化、Williamson合成法等共七步反应, 首次合成了从海洋真菌中分离的天然产物联烯Xyloallenoid F, 总收率25.4%, 目标化合物经IR, ¹H NMR, ¹³C NMR, MS和元素分析进行测定和结构表征.     

双核磺化酞菁铜(Ⅱ)催化氧化α-萘酚

本文研究了以乙醇为溶剂,CaCl_2为助催化剂,双核磺化酞菁铜(Ⅱ)催化氧化α-萘酚制备α-萘醌的各种因素。提出了可能的反应机理。     

氢氧化镁的结晶习性研究

本文用负离子配位多面体模型探讨了NaOH水热介质中Mg(OH)2晶体的结晶习性。提出了Mg(OH)2的水热改性属溶解-结晶机制、生长基元为Mg(OH)6^4-八面体的观点。Mg(OH)2-NaOH-H2O体系高温热力学计算和电阻在线检测结果间接验证了生长基元论点。理论推导表明：Mg(OH)6^4-八面体的共棱连接方式决定了Mg(OH)2的结晶习性。     

钐(II)类卡宾CH3SmCH2I与乙烯环丙烷化反应及溶剂化效应的理论研究

用密度泛函B3LYP方法研究了过渡金属钐类卡宾与乙烯的环丙烷化反应的机理. 对钐类卡宾试剂CH₃SmCH₂I和CH₂CH₂反应的反应物、中间体、过渡态和产物构型的全部结构几何参数进行了优化, 并计算了THF溶液的溶剂化效应, 用内禀反应坐标(IRC)计算和频率分析方法, 对过渡态进行了验证. 结果表明: CH₃SmCH₂I与CH₂CH₂环丙烷化反应按亚甲基转移机理(通道A)和卡宾金属化机理(通道B)都可以进行, 与锂类卡宾的反应机理相同, 通道A比通道B反应的势垒降低了14.65 kJ/mol. 溶剂化效应使通道B比通道A的反应势垒大幅度提高, 更有利于反应沿通道A进行, 而不利于通道B.     

Theoretical study of the reaction of Cu with OCS

The reactivity of Cu⁺ with OCS on both singlet and triplet potential energy surfaces (PES) has been investigated at the UB3LYP/6-311+G(d) level. The object of this investigation was the elucidation of the reaction mechanism. The calculated results indicated that both the C–S and C–O bond activations proceed via an insertion–elimination mechanism. Intersystem crossing between the singlet and triplet surfaces may occur along both the C–S and C–O bond activation branches. The ground states of CuS⁺ and CuO⁺ were found to be triplets, whereas CuCO⁺ and CuCS⁺ have singlet ground states. The C–S bond activation is energetically much more favorable than the C–O bond activation. All theoretical results are in line with early experiments.     

Water mist attenuates guided laser based on Monte Carlo method

The round-trip attenuating process of lasers used for guiding in artificial water mists is studied with the Monte-Carlo method. A new way for confirming the scattering directions of photons is established based on calculating Mie cumulative probability distribution function of the polydisperse mist and user defined function fitting by Matlab. Two Monte-Carlo methods for photons tracking are mentioned and their efficiencies are discussed and balanced in this paper. A conclusion is come to that the Wight method is evidently more efficiency than the Event method, and the former is adopted in this paper. The radiuses of frequently-used water mists are usually in the range of 10¹–10² μm which are found to be suited to attenuate the 10.6 μm laser and can be used for laser stealth. But the effect is worse for 1.06 μm laser.     

过渡金属化合物OsB2与OsO2低压缩性的第一性原理计算研究

利用基于密度泛函理论平面波赝势法的第一性原理计算,研究了过渡金属化合物OsB2和OsO2的金红石相、黄铁矿相与萤石相三种结构在高压下的状态方程和结构特性以及OsO2可能的高压相变.理论计算结果支持OsB2与OsO2的萤石相是潜在超低可压缩性的硬性材料.同时,也分析了它们的电子结构,力求理解大体变模量和高硬度的微观机制.结果表明,可以利用过渡金属高的价电子浓度,掺入硼、氧、碳、氮等轻的元素形成强的方向键,这可能提供了一种合成超硬材料的新途径.     

气相中W~+活化CO_2分解的自旋禁阻反应机理

用密度泛函理论中的UB3LYP方法,对W采用相对论校正赝势基组(SDD),对C、O采用6-311+G(3d)基组,研究了气相中不同自旋态W+活化CO2分解的反应机理.计算结果表明,W+活化CO2分解反应以六重态进入反应通道,经过六重态势能面到四重态势能面的系间窜越(ISC),最后产物WO+和CO以四重态离开反应通道.运用Harvey方法优化出最低能量交叉点(MECP),并计算了MECP处的自旋-轨道耦合(SOC)常数(494.95cm-1),势能面的交叉和在MECP处较强的自旋-轨道耦合作用降低了自旋禁阻反应能垒,为反应提供了一条低能反应路径,反应总放热量为122.33kJ.mol-1.