基于扫描探针显微镜(SPM)的高密度信息存储

随着信息技术的飞速发展,高密度信息存储的研究成为国际上备受关注的研究领域。扫描探针显微技术（SPM）通过改变材料的光、电、磁等局域特性可以实现纳米尺度的信息存储,成为提高信息存储密度的最有效手段之一。本文从信息存储材料和技术角度综述了基于SPM的高密度信息存储最近的研究进展,并讨论了其将来的研究和发展方向。     

一种增强型荧光探针检测CN-及在细胞中的应用

以甲醇为溶剂,2-羟基-1-萘甲醛和2-氨甲基吡啶1∶1结合生成了一种简单的希夫碱增强型荧光探针(L)。该探针在DMSO∶H₂O(3∶2,V/V)的水溶液中加入CN^-后,荧光可增强8倍,线性范围为0~120×10^-5M,通过核磁滴定证明此作用机理为CN^-的去质子化作用。此外,通过荧光共聚焦成像,化合物L可高效选择性地检测人体SiHa癌细胞中的CN^-。     

二茂铁金属有机液晶的合成,结构及介晶性研究

我们曾研究了以季铵盐作为相转移催化剂,通过二茂铁的芳基化反应,合成了一系列带活泼官能团的二茂铁衍生物［１］。这些衍生物可作为合成二茂铁非线性光学材料、液晶材料的良好中间体［２－４］。为了探索分子几何结构与介晶性能之间的关系和制备结构新颖、稳定性能好、...     

共价有机骨架的合成及其在气体吸附存储方面的应用

共价有机骨架(COFs)是一种新型的纳米结构材料,由于其独特的性质而受到人们的广泛关注.COFs的结晶.度高,孔径可调,比表面积大,具有良好的抗氧化性能和独特的分子结构,在能源、环境等方面得到了广泛的应用.COFs材料有较高的应用价值,促使人们不断努力研究其基本性质,并调控其结构和功能来提高性能.通过COFs的可设计性...     

扫描探针显微镜在导电聚合物研究中的应用

扫描探针显微镜在导电聚合物研究中的应用;扫描探针显微镜;导电聚合物;综述     

信息存储的分子材料——自旋转换配合物

从化学角度综述了一类具有信息存储功能的分子材料———自旋转换配合物。介绍了配合物的自旋转换现象；自旋转换配合物的表征；自旋转换配合物用于信息存储器件应具备的条件及实用自旋转换配合物的研制近况及展望。     

MOFs在催化有机分子转化中的应用

金属有机框架化合物（MOF）,又称多孔性配位聚合物,是有机配体与金属离子自组装而成的一类新型有机-无机杂化多孔材料,是纳米材料的重要组成部分。与其他多孔材料相比,MOFs具有较大的比表面积、高的孔隙率以及结构和性质可调等特性,使其在非均相催化领域具有良好的应用前景。本文首先对MOFs催化的背景进行简述,然后对近年来报道的MOFs用于有机分子催化转化反应的进展进行了综述及展望,以期为MOFs催化有机反应的设计和开发提供参考。     

一种增强型荧光探针对Al~(3+)的识别检测及细胞成像研究

以2-羟基-1-萘甲醛和2-氨甲基吡啶为原料合成了一种简单的希夫碱化合物(L)。L作为增强型荧光探针,在缓冲水溶液中可选择性检测Al~(3+),检测限为80.5nmol/L,远低于世界卫生组织规定的饮用水中Al~(3+)的上限值(7.41μmol/L)。通过荧光共聚焦成像,化合物L可高效地检测人体SiHa癌细胞内的Al~(3+)。     

稀土磁光材料在信息存储中的应用

稀土磁光信息存储材料集磁记录与光记录于一体,具有极大的法拉弟增强效应,高的存储密度,反复可擦写功能和抗毁伤性,使其成为下一代磁光存储及紫蓝域信息存储媒体的佼佼者.本文就几种稀土磁光材料的发展历史、特性及应用特点作了详尽叙述,并对相关领域最新研究成果、新颖制备方法和未来潜在的应用给予论述.     

DNA分子在气液界面的组装相变特性及其LB膜结构研究

对十八胺与DNA在气液界面上组装及其相变过程进行了研究,利用AFM观察了不 同压力下转移的DNA复合LB膜结构。发现在低表面压时,DNA复合单分子膜表现为技 术发散的分形结构;随着压力的升高,DNA复合膜逐渐由紧密的网状排布结构变为 团聚的块状和团簇结构。表明通过调节膜压,可使膜内DNA分子的构象发生大的变 化,从而生成具有特定形态的二维纳米图案。这种具有特殊形态和结构的DNA LB膜 可望为合成新型生物纳米结构有序功能体系提供模板。     

Synthesis and crystal structure of an unexpected anionic trinuclear cobalt(III) complex with ferrocenyl-containing tridentate ONO donor Schiff base ligands

The tridentate ONO-donor Schiff base ligand derived from the condensation of 1-ferrocenyl-1,3-butanedione and 2-aminophenol, generated in situ and treated further with potassium tert-butoxide, reacted in THF with Co(NO₃)₂·6H₂O in the presence of pyridine to afford the ionic complex [{(η⁵-C₅H₅)Fe(η⁵-C₅H₄)-C(O)CH=C(CH₃)N-C₆H₄-2-O}₂Co(III)]^-[K(HOCH₂CH₃)₂]⁺ (1, 50% yield). Compound 1 was characterized by elemental analysis, FT-IR, and multidimensional ¹H and ¹³C NMR spectroscopy. Single-crystal X-ray diffraction reveals that the two metalloligands are meridionally coordinated to a Co(III) ion that adopts a slightly distorted octahedral geometry. The doubly solvated potassium counter-ion is asymmetrically positioned with respect to the two metalloligands. Such an arrangement allows the observation by ¹H NMR of restricted rotation of the ferrocenyl units and the splitting of both carbonyl and imine carbons, thus suggesting that the structure observed in the solid state is retained in solution. Complex 1 exhibits in its cyclic voltammetry curve two anodic reversible waves attributed to the oxidation of Co(III)-phenolates into Co(III)-phenoxyl radical and that of the ferrocenyl fragment into its ferrocenium counterpart.     

局域和长程杂化密度泛函研究推拉结构有机发光分子

用含时密度泛函方法研究了具有推拉结构的有机发光材料3-(二氰亚甲基)-5,5-二甲基-1-(4-[9-咔唑基]-苯乙烯基)环己烯(DCDCC)的吸收和荧光光谱, 并考虑了溶剂效应. 通过与实验光谱的比较, 重点评价了包括局域和长程在内的8种交换泛函. 结果表明泛函的选择对结果的可靠性至关重要, 在密度泛函和含时密度泛函理论框架下, 包含44% Hartree Fock交换泛函的BMK杂化函数联同连续极化模型和中等大小的基组最适合研究DCDCC分子的光谱性质. 此外, 尽管DCDCC分子内电荷转移并没有强致发出双荧光, 但仍然可以用平面分子内电荷转移和扭转分子内电荷转移模型解释DCDCC激发态的结构. BMK泛函计算的结果表明DCDCC的激发态结构支持平面分子内电荷转移模型.     

Interaction of a Schiff-base fluorescent sensor with Al3+: experimental and computational studies

A fluorescent Al³⁺ chemo-sensor, 1-phenyl-3-methyl-5-hydroxypyrazole-4-acetone-(3′,4′-dimethylpyrrole-2′-formyl) hydrazone (L), has been synthesized and characterized. L can detect Al³⁺ in ethanol solution with a significant fluorescence enhancement of a turn-on ratio over 155-fold due to the formation of a 1?:?1 complex which is based on the molar ratio between L and Al³⁺ ions, and the 1?:?1 stoichiometric complexation can be obtained from density functional theory calculations. No significant interference of other metal ions such as Na⁺, K⁺, Mg²⁺, Ca²⁺, Ni²⁺, Zn²⁺, Cd²⁺, Co²⁺, Cu²⁺, Fe³⁺, Cr³⁺, Pb²⁺, and Ag⁺ was found. The detection limit for Al³⁺ was 5?×?10^?9?M in ethanol.     

磷酸锆及其衍生物催化剂在有机反应中的应用

简要综述了近年来磷酸锆及其衍生物催化剂的制备、组成、结构与催化性能的关系、催化机理及其在有机反应中的应用。     

Synthesis and Thermal Properties of a Novel Schiff Base Oligomer with a Double Azomethine Group and its Co(II) and Mn(II) Complexes

Schiff base oligomer of N,N′‐bis (2,4‐dihydroxybenzylidene) 1,2‐phenylenediamine (DHBPDA), with a double azomethine group, was synthesized from the oxidative polycondensation (OP) reaction with NaOCl as an oxidant in an aqueous alkaline medium at 90°C. About 75% DHBPDA was converted to O‐DHBPDA. The structures of the products were studied by UV‐Vis, FT‐IR, ¹H‐NMR, ¹³C‐NMR and elemental analysis. According to Gel Permeation Chromatography (GPC) analysis of O‐DHBPDA, the number average molecular weight (M_n), weight average molecular weight (M_w) and PDI values were found to be 4328 g mol^?1, 6228 g mol^?1 and 1.43, respectively. TG/DTA analyses were shown to be stable of O‐DHBPDA against thermo‐oxidative decomposition. During the polycondensation reaction, a part of the azomethine (‐CH?N‐) groups oxidized to aldehyde (CHO) group (10–12%). Oligomer‐metal complexes of oligo‐N,N′‐bis (2,4‐dihydroxybenzylidene) 1,2‐phenylenediamine (O‐DHBPDA) with Co(II) and Mn(II) were synthesized and characterized by FT‐IR, UV‐Vis, TG‐DTA and Atomic Absorption Spectroscopy (AAS). The residue of DHBPDA, O‐DHBPDA, O‐DHBPDA‐Co and O‐DHBPDA‐Mn were found to be 0%, 3.65%, 11.67%, and 9.20%, respectively at 1000°C.     

Application of a Carbon Paste Electrode Modified with a Schiff Base Ligand to Mercury Speciation in Water

A carbon paste electrode, modified with benzylbisthiosemicarbazone is used for mercury speciation in water samples. Mercury ion is selectively accumulated on the electrode surface at open circuit and its analysis was performed by cyclic voltammetry or square‐wave voltammetry (SWV). A detection limit of 8 μg L^?1 (3σ) was found for 15 min of accumulation using SWV as measurement technique. The effect of several metallic ions and organic substances on voltammetric signal is examined. For speciation purposes, a ligand competition methodology between ligands in solution and electrode is used. Model mercury complexes are characterized as a function of their dissociation kinetics. The method was applied to mercury speciation in water samples from the Jarama River in Madrid.     

Synthesis and crystal structure of three new copper(II) complexes with a tridentate amine and its Schiff bases

Three new mononuclear complexes of copper(II), viz. [Cu(L)(N₃)Cl] (1), [Cu(L′)(H₂O)]ClO₄ (2) and [Cu(L″)] (3) where L = N-(3-aminopropyl)-N-methylpropane-1,3-diamine, L′ = 2-(N-{3-[(3-aminopropyl)(methyl)amino]propyl}ethanimidoyl)phenolate ion and L″ = 2,2′-{(methylimino)bis[propane-3,1-diylnitrilo(1E)eth-1-yl-1-ylidene]}diphenolate ion, have been prepared. The synthesis of complex 1 has been achieved by reacting copper chloride with the triamine (L) and sodium azide in a 1:1:1 M ratio. The other two compounds have been synthesized by the reaction of copper perchlorate with the same triamine, L, plus 2-hydroxyacetophenone in a molar ratio of 1:1:1 (for 2) and 1:1:2 (for 3), so that the respective tetradentate and pentadentate Schiff bases HL′ and H₂L″ are formed in situ to bind the copper(II) ions. The complexes have been characterized by microanalytical, spectroscopic and single crystal X-ray diffraction studies. Structural studies reveal that the mononuclear units of all the three complexes adopt a distorted square pyramidal geometry and are held together by either intermolecular H-bonding (in 1 and 2) or C-H?π interactions (in 3) to form supramolecular networks in the solid state.     

Study of the Preparation of a Modified Lubricant Using a W/O Microemulsion Reactor and a Cyclic Voltammetry Study of Rubbing Steel S45C with Lubricants

A successful preparation of a Schiff base copper complex was carried out directly in rap oil, using a W/O microemulsion reactor. The prepared Schiff base copper complex dispersed equably and spontaneously in the oil. Owing to a modification of the rap oil, by addition of 2%wt of Cu (II) chelate of bissalicylaldehyde-ethylenediamine, the friction coefficient decreased by 80% compared to that of the original one. It was verified by energy dispersive spectroscopy (EDS) and x-ray photoelectron spectroscopy (XPS) analyses that steel/steel rubbing pairs underwent a selective transferring process with such modified lubricants. It was suggested that the mechanism for the improvement in the tribological characteristics of the modified lubricants was due to a selective transferring effect. The Cu (II) chelate of bissalicylaldehyde-ethylenediamine not only served as an additive in the rap oil, but also self-assembled on the surface of the 100Cr6 steel. The self-assembled monolayer (SAM) was examined using SEM techniques. The SAM was characterized with cyclic voltammetry (CV). It indicated that the SAM could activate the rubbing surface of 100Cr6 steel, which benefited the tribological chemical reaction.     

Preparation and Application of a Novel Core-Shell Organic Nanoparticle as a Fluorescence Probe in the Determination of Nucleic Acids

A novel type of core-shell organic nanoparticles (pyrene/poly-acrylic acid; PAA) has been prepared by precipitation polymerization under ultrasonic irradiation. It was characterized by transmission electron microscopy (TEM) and fluorescence lifetime. The lifetime is about 5µs, which is much longer than conventional organic dyes fluorescence lifetime. As the surface of the core-shell organic nanoparticles is covered with abundant carboxylic groups, the nanoparticles are water-soluble, stable and biocompatible. At pH 6.4, maximum fluorescence is produced, with the maximum excitation and emission wavelengths of 338nm and 397nm, respectively. Under optimum conditions, the calibration graphs are linear over the range of 4.0×10^–51.0×10^–2mgmL^–1 for calf thymus DNA (ct-DNA) and 2.0×10^–41.0×10^–2mgmL^–1 for fish sperm DNA (fs-DNA). The detection limits were 3.6×10^–5mgmL^–1 and 1.4×10^–4mgmL^–1 for ct-DNA and fs-DNA, respectively. The method was applied to the determination of ct-DNA and fs-DNA in synthetic samples and the results were satisfactory. The method is sensitive, stable, rapid and tolerant towards most interfering substances.     

粉煤灰-硫酸固相反应中表面形貌与化学组成变化特性的表面分析

燃煤电厂排放的粉煤灰是重要的空气污染源之一。目前我国年排放粉煤灰约1·4亿吨,累积堆放5亿吨,占地24万多亩,处置与综合利用粉煤灰具有重要的环保意义。粉煤灰用于污水处理,可有效降低废水中COD、挥发酚及重金属含量[1,2]。我们提出固定化絮凝剂的新概念[3],以粉煤灰为主要原