A New Bismuth(Ⅲ) Iodide Inorganic/organic Hybrid Solid Containing Large Heterocyclic Conjugated Organic Ligand: Synthesis,Properties and Calculations

A new bismuth(III) iodide inorganic/organic hybrid containing larger heterocyclic conjugated organic ligand, [(dppz)2Bi2I6]·2DMF(1)(dppz = dipyrido[3,2-a:2',3'-c]phenazine), has been synthesized by solution process and structurally determined by X-ray diffraction method. 1 crystallizes in triclinic, space group P1 with Mr = 1844.08, a = 9.215(5), b = 11.488(6), c = 12.424(9) ?, α = 106.66(2), β = 90.84(2), γ = 92.34(2)°, V = 1258.5(13)?3, Z = 1, Dc = 2.433 g/cm3, F(000) = 830, μ(MoKα) = 10.702 mm–1, the final R = 0.0834 and wR = 0.1947 for 2749 observed reflections with I 2σ(I). 1 consists of a dimeric structure [(dppz)2Bi2I6], in which two [(dppz)BiI3] fragments are bridged by a pair of iodine atoms. Hydrogen bonds and π···π stacking interactions contribute to the structural extension and stabilization. Experimental band gap of about 2.13 eV indicates its semiconductor nature. The optical absorption spectrum and electronic structure were also discussed.     

一种改进的递归流分类算法

递归流分类(RFC)算法是目前具有代表性的一种流分类算法，其时间复杂度是O(1)，匹配速度非常快，但是它难以根据字符串类型域进行流分类．本文结合Aho-Corasick多关键字匹配算法的基本思想，通过为字符串类型域构造匹配自动机和CBM数组，扩充了RFC算法，使新算法能够根据字符串域进行流分类．试验结果表明，改进的算法性能良好，并且适用于某些不能直接使用原RFC算法的应用领域．