A Porous 3D Supramolecular Architecture of Cd(Ⅱ) Complex with Water Clusters as Pillars

A supramolecular complex of Cd(Ⅱ) with 1D water tapes as pillars[Cd2(dpa)2(phen)2- (H2O)2]·6H2O 1 (H2dpa = diphenic acid, phen = phenanthroline), has been synthesized and characterized by elemental analysis, IR spectroscopy, and single-crystal X-ray diffraction analysis. The crystal is of triclinic, space group Pī with a = 9.7029(4), b = 11.9601(5), c = 12.1788(4) A, a = 71.6990(10), β = 71.8740(10), γ = 74.4680(10)°, V = 1252.39(8) A3 C52H48Cd2N4O16, Mr = 1209.76, Z = 1, Dc = 1.604 g/cm3,μ = 0.925 mm-1, F(000) = 612, R = 0.0679 and wR = 0.2514 for 3870 observed reflections (Ⅰ > 2σ(Ⅰ)). Two intramolecular Cd(Ⅱ) centers of this complex are encircled by two dpa2- ligands forming an 18-membered ring, which is further assembled into a pillared three-dimensional (3D) supramolecular architecture through the synergetic effect of intermolecular face-to-face π…π stacking and weak O-H…O hydrogen-bonding interactions. Moreover, this complex exhibits photoluminescence with the main emission bands located at about 456 nm upon excitation at 355 nm in the solid state at room temperature.     

Structure of the 1:1 complex of dimethyl sulfoxide with hydroquinone: Supramolecular architecture based on D-H⋯A hydrogen bonds (D = O,C; A = O, π)

The hydroquinone-dimethyl sulfoxide-toluene system was investigated by thermal and X-ray diffraction analyses. The crystal structure of the 1:1 complex of hydroquinone with dimethyl sulfoxide was determined. Crystal data: C₈H₁₂O₃S, M = 188.24, triclinic system, space group P1¯, unit cell parameters: a = 7.4202(2) Å, b = 8.4046(3) Å, c = 8.7340(3) Å; α = 100.830(1)°, β = 99.794(1)°, γ = 114.129(1)°; V = 469.35(4) ų, Z = 2, d _calc = 1.332 g/cm³, R1 = 0.028, T = 100 K. The molecules are linked in a supramolecular assembly via D-H...A hydrogen bonds (D = O, C; A = O, π).     

Structural characterization,thermal stability,and solvent de-/ad-sorption behavior of two d10 M(II) (M = Cd and Zn) coordination polymers constructed by 1,3,5-tris(4-pyridylsulfanyl-methyl)-2,4,6-trimethyl-benzene (L1)

Two d¹⁰ M(II) (M = Cd and Zn) coordination polymers (CPs) with chemical formulas, {[Cd(L¹)(NCS)₂(H₂O)]⋅C₂H₅OH}_n (1) , and {[Zn(L¹)(NCS)₂]⋅C₂H₅OH⋅0.5H₂O}_n (2) (L¹ = 1,3,5-tris(4-pyridylsulfanylmethyl)-2,4,6-trimethylbenzene) were synthesized and structurally characterized by single-crystal x-ray diffraction method. In compound 1 , the coordination environment of Cd(II) ion is distorted octahedral bonded to three nitrogen donors from three L¹ ligands located in a facial-position, two nitrogen donors from NCS⁻ and one water molecule. The L¹ acts as a bridge ligand with tris-monodentate coordination mode in a cis-cis-cis structural conformation, connecting the Cd(II) to form a two-dimensional (2D) zigzag-like layered metal-organic frameworks. Adjacent 2D layers are then arranged orderly in an ABAB manner to complete its three-dimensional (3D) supramolecular architecture. In compound 2 , the coordination environment of Zn(II) ion is distorted tetrahedral bonded to two nitrogen donors from two L¹ ligands and two nitrogen donors from two NCS⁻ ligands. The L¹ acts as a bridge ligand with bis-monodentate coordination mode in a cis-cis-cis structural conformation, connecting the Zn(II) ions to form a one-dimensional (1D) zigzag-like polymeric chain. Adjacent chains are arranged orderly in an alternate ABAB manner to generate a 2D framework and then further arranged in an AAA manner to complete its 3D supramolecular architecture. The structural characterization as well as thermal-stability and solvents de-/ad-sorption behavior of 1 and 2 are studied and discussed in details.     

基于2,4′-二羧基二苯甲酮构筑的具有一维梯状链和一维隧道的三维超分子体系

采用水热法设计合成了两个新型三维超分子化合物H₂L·H₂O (1)和[Ag(bpy)₂]·HL·H₂O (2) (其中bpy=2,2'-联吡啶, H₂L=2,4′-二羧基二苯甲酮),晶体结构分析表明,它们均是通过氢键采用不同的连接方式拓展而成。其中,化合物1 是2,4′-二羧基二苯甲酮和水分子通过O–H···O氢键形成的一维梯状链扩展构筑的三维超分子体系;化合物2 则是2,4′-二羧基二苯甲酮和水分子通过两种氢键形成含有一维隧道的三维超分子体系。有趣的是,[Ag(bpy)₂]⁺ 阳离子通过π–π 堆积和弱的Ag···Ag相互作用连在一起,进而以客体形式填充其中。荧光性质研究表明,由于存在bpy的螯合与堆积效应,化合物2相比配体和化合物1,其荧光发射峰发生红移。     

Constructing Interfacial Energy Transfer for Photon Up‐ and Down‐Conversion from Lanthanides in a Core–Shell Nanostructure

We report a new mechanistic strategy for controlling and modifying the photon emission of lanthanides in a core–shell nanostructure by using interfacial energy transfer. By taking advantage of this mechanism with Gd³⁺ as the energy donor, we have realized efficient up‐ and down‐converted emissions from a series of lanthanide emitters (Eu³⁺, Tb³⁺, Dy³⁺, and Sm³⁺) in these core–shell nanoparticles, which do not need a migratory host sublattice. Moreover, we have demonstrated that the Gd³⁺‐mediated interfacial energy transfer, in contrast to energy migration, is the leading process contributing to the photon emission of lanthanide dopants for the NaGdF₄@NaGdF₄ core–shell system. Our finding suggests a new direction for research into better control of energy transfer at the nanometer length scale, which would help to stimulate new concepts for designing and improving photon emission of the lanthanide‐based luminescent materials.     

基于PSO算法的RoboCup2D机器人研究

对机器人体系结构、动作学习及行为的组织方式进行了研究,以演化计算为基本方法,以RoboCup2D为平台,设计了基于PSO算法的足球机器人的体系结构,解决感知、动作、和规划问题;在训练环境下,形成感知规则,优化感知相关参数,得到对信息高效快速的感知方法,并根据指定的粒度、功能、参数,对RoboCup2D机器人的原子动作进行了组合优化,得到一组带参数和执行效果描述的粒子动作;最后在赛场环境和任务驱动下,搜索粒子动作并进行组织规划,得到完成特定任务的机器人行为;RoboCup2D仿真实验表明,演化计算方法不仅能利用原子动作进行组合优化,得到适应于不同条件的粒子动作,而且能通过其在线搜索粒子动作,动态组成机器人行为;基于演化计算的足球机器人能更好地完成跑位、截球、带球、传球等任务,具有更强的适应性。     

Amphiphilic block and statistical copolymers with pendant glucose residues: Controlled synthesis by living cationic polymerization and the effect of copolymer architecture on their properties

Amphiphilic block and statistical copolymers of vinyl ethers (VEs) with pendant glucose residues were synthesized by the living cationic polymerization of isobutyl VE (IBVE) and a VE carrying 1,2:5,6‐di‐O‐isopropylidene‐D ‐glucose (IpGlcVE), followed by deprotection. The block copolymer was prepared by a two‐stage sequential block copolymerization, whereas the statistical copolymer was obtained by the copolymerization of a mixture of the two monomers. The monomer reactivity ratios estimated with the statistical copolymerization were r₁ (IBVE) = 1.65 and r₂ (IpGlcVE) = 1.15. The obtained statistical copolymers were nearly uniform with the comonomer composition along the main chain. Both the block and statistical copolymers had narrow molecular weight distributions (weight‐average molecular weight/number‐average molecular weight ∼ 1.1). Gel permeation chromatography, static light scattering, and spin–lattice relaxation time measurements in a selective solvent revealed that the block copolymer formed multimolecular micelles, possibly with a hydrophobic poly(IBVE) core and a glucose‐carrying poly(VE) shell, whereas the statistical copolymer with nearly the same molecular weight and segment composition was molecularly dispersed in solution. The surface properties of the solvent‐cast films of the block and statistical copolymer were also investigated with the contact‐angle measurement. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 459–467, 2001     

Mach-Zehnder interferometer-based tree architecture for all-optical logic and arithmetic operations

Interferometric devices for optical processing have been of great interest in recent years. Semiconductor optical amplifier (SOA)-based Mach-Zehnder interferometer (MZI) has already taken a significant role in the field of ultra-fast all-optical signal processing. Optical tree architecture (OTA) provides important contributions in optical interconnecting networks. In this communication, we have tried to exploit the advantages of both OTA and SOA-based MZI switches. We have proposed SOA-MZI-based tree architecture, a new and alternative scheme, for integrated all-optical logic and arithmetic operations. This architecture can enable one to perform all-optical processing of signals, including two input logic operations, half-adder, full-adder, full-subtractor, one-bit data comparator, etc.     

Synthesis and X-ray crystallographic studies of Ni (II) and Cu (II) complexes of [5-(4-pyridyl)-1,3,4] oxadiazole-2-thione/thiol formed by transformation of N-(pyridine-4-carbonyl)-hydrazine carbodithioate in the presence of ethylenediamine

The reaction of [M(H₂L)₂] [M = Ni(II) Cu(II)] (K⁺H₂L⁻ = N-(pyridine-4-carbonyl)-hydrazine carbodithioate) with excess of ethylenediamine (en) gave mixed ligand complexes [Ni(en)₂(4-pytone)₂] (4-pytone = 5-(4-pyridyl)-1,3,4-oxadiazole-2-thione), and [Cu(en)₂](4-pytol)₂·H₂O (4-pytol = 5-(4-pyridyl)-1,3,4-oxadiazole-2-thiol). The metal complexes have been characterized with the aid of elemental analyses, IR, magnetic susceptibility and single crystal X-ray studies. Complexes (1) and (2) crystallize in monoclinic system, space group P_{1 21}/n₁ and C₂/c, respectively. The ligand after cyclization is present in the deprotonated thiol form in the Cu(II) complex where it is ionically bonded through sulfur. In the Ni(II) complex (1) bonding of the ligand take place through oxadiazole nitrogen and the ligand exists as the thione form.