Acidichromism in the LB film of bolaform Schiff base

A bolaform(BNC 10)and single-headed(HNOA)amphiphilic Schiff bases containing naphthyl group were designed and their Langmuir-Blodgett films were investigated.It was found that both the LB films show acidichromism,i.e.a reversible color change upon alternatively exposing the films to HCl and NH_3 gases,respectively.It was further found that the bolaform Schiff bases film could trap NH_3 gas during the acidichromic process.     

One New Schiff Base Complex with One in Situ Synthesized Ligand： Synthesis and Structure

1 INTRODUCTION The transition-metal Schiff base complexes have attracted much attention due to their beautiful struc- tures, multifunctions like catalysis[1～3] and materials science[4～6]. Recently, some Schiff base complexes based on guanidinate ligands have been explored[7～9], and most of them were synthesized by stepwise reactions. Due to the steric and electrical flexibility and abundant donor functionality of the guanidinate species, the ligand may adopt various coordination modes.…     

Synthesis of TiO2 Nanoparticles via a Ti（IV） Complex with Stearic Acid and the Photocatalytic Activity for Organic Oxidation

The nano-sized particles of TiO2 were prepared by thermal decomposition of titanium (IV) tetrabutanoxide complex with stearic acid at 450℃ in the air.It was observed that the amount of stearic acid,used initially for the complex synthesis in 2-propanol at 25℃,had great influence on the physical properties of the prepared TiO2 including crystal structure, the particle size,surface area and the adsorption capacity for organic substrate of a textile dye X3B in eater,and thereafter the photocatalytic activity for the dye oxidation.Some samples displayed lower adsorption capacity for the organic substrate in water than a TiO2 of Degussa p25,but higher photocatalytic activity for the organic oxidation.Possible reason for the observed difference was discussed in the text.     

Orientations of Rare—earth—containing Heteropolyoxometalates with Different Sizes in the Interlayer of Synthetic Multibilayer Films

Three rare-earth-containing heteropolyoxometalates with different sizes, Na9[Eu(W5O18)2],K13[Eu(SiW11O39)2], and K17[Eu(P2W17O61)2], have been incorporated by self-assembly into the interlayer of synthetic multibilayer films of dimethyldioctadecylammonium chloride and exhibited different orientations.     

Thermochemical Study of Acid—Base Reactions in a Glycyl-Tyrosine Aqueous Solution

Thermal effects of the interaction between a glycyl-tyrosine solution and solutions of HNO₃ and KOH in different pH ranges at a temperature of 298.15 K and ionic strengths of 0.25, 0.5, and 0.75 (KNO₃) are measured via calorimetry. Thermal effects of the stepwise dissociation of the dipeptide are determined. Standard thermodynamic characteristics Δ_rH°, Δ_rG°, and Δ_rS° of acid—base reactions in aqueous solutions of glycyl-tyrosine are calculated. The relationship between the thermodynamic characteristics of dipeptide dissociation and the structure of this compound is examined.     

The Influence of Temperature on the Heat Effects of Acid—Base Interaction in Aqueous Solutions of Citric Acid

The heat effects of interaction of a solution of citric acid with solutions of HNO₃ and KOH at 288.15, 298.15, and 308.15 K and ionic strength values 0.5, 1.0, and 1.5 (KNO₃) were measured calorimetrically. The heat effects of acid dissociation were calculated using the HEAT program. The standard thermodynamic characteristics of step dissociation of citric acid were determined.     

Synthesis,Crystal Structure and Cytotoxic Activity of a Zinc（Ⅱ） Complex of the Schiff Base Derived from S-benzyldithiocarbazate

A novel zinc(Ⅱ) complex of empirical formula,ZnL2(L=anionic forms of S-benzyl-β-N-(2,4-dichlorobenzylidene) hydrazine carbodithioate),has been synthesized and characterized by elemental analysis,IR spectra and single-crystal X-ray diffraction.The crystal belongs to the triclinic system,space group P with a = 9.3168(9),b = 13.0353(13),c = 14.7702(15) ,α = 71.2860(10),= 87.5140(10),γ = 79.4480(10)o,V = 1670.0(3) 3,Z = 2,Mr = 773.93,Dc = 1.539 g/cm3,μ = 1.334 mm-1,F(000) = 784,the final R = 0.0403 and wR = 0.0800 for 4060 observed reflections with I>2(I).In the crystal structure,the zinc(Ⅱ) complex has a distorted tetrahedral geometry in which the zinc ion is coordinated by the nitrogen and sulfur atoms from two Schiff base ligands,respectively.The preliminary bioassay indicates that the Schiff base and its zinc complex exhibit inhibitory activity against the human gastric cancer cell lines(MKN45) and hepatoma cell lines(HepG2).     

Chemical Reactions of Surfactants with Acid–Base Dyes and Determination of Imidazolines in the Air of the Working Area

Reactions of acid–base monoazo dyes with polyamine surfactants were studied. The ratios of components in the resulting compounds were determined; the stability constants and molar absorptivities were calculated. A mechanism was proposed for the reaction of monoazo dyes with amine and imidazoline surfactants with the formation of macroheterocycles. Approaches to predicting analytical reactions between monoazo dyes and surfactants were substantiated. The dependence of the extraction of these compounds on the pH of the aqueous phase and the concentrations of NaCl and ethanol was studied. The optimal conditions for extraction separation were found, and a procedure was developed for the spectrophotometric determination of 1-(-hydroxyethyl)-2-heptadecenyl-2-imidazoline (Imidazoline 17) and 1,1"-bis(-hydroxyethyl)-2-heptadecenyl-2-imidazolonium chloride (Imidastat O) in the air of the working area using Methyl Orange as the reagent. The determination limits were 0.025 and 0.12 g/mL, respectively. A sampling procedure was developed for the determination of Imidazoline 17 and Imidastat O in the air with determination limits of 0.05 and 0.25 mg/m³, respectively, for sampling 15 L of air to 60% ethanol.     

Synthesis,Crystal Structure and Electrochemistry Properties of a Cobalt(Ⅱ) Complex Based on Asymmetry Schiff Base Ligand

A new cobalt(II) complex [Co(NO2-salen)2]·1.5H2O containing mono acetalization Schiff base ligand(NO2-salen = N-5-nitro-salicylideneamino ethanato) has been prepared through one-pot template condensation, and has been structurally characterized by elemental analysis, IR spectra and X-ray diffraction. It is formulated as C18H23CoN6O7.5, crystallizes in the hexagonal system, space group of R-3c with α = 25.895(18), b = 25.895(18), c = 35.075(6), γ = 120o, V = 20368(3) and Z = 36. The ligand of 5-nitrosalicylaldehyde-ethylene-diamine takes unusual mono asymmetry mode. The Co(II) ion exhibits a coordination number of six, and assumes a distorted octahedral geometry with a N2O4 donor set. The neutral monomeric units of [Co(NO2-salen)2]·1.5H2O are linked into a one-dimensional(1D) structure via the intermolecular hydrogen bonds and weak π-π stacking interactions. Cyclic-voltammetry measurement reveals the oxidation and reduction processes for the complex are irreversible in nature.     

Langmuir-Blodgett Films from Schiff Base Aluminium (Ⅲ) Complex

The characteristics of the LB films of Schiff base aluminium(Ⅲ), tris(2-hydroxy-5-nitro-N-dodecyl-benzylideneaminato) aluminium(Ⅲ)[Al(TA12)_3], were studied. The surface pressure-area(π-A) isotherm of Al(TA12)_3 in the pure water subphase was investigated. The molecular area, 0.48 nm~2, is one-third of the expected value that indicates the formation of an aggregate. The Langmuir-Blodgett(LB) films of Al(TA12)_3 were transferred and characterized. The UV-Vis spectra and the AFM image both confirmed that the J-aggregates formed. The polarized UV-Vis spectra indicated that the complex plane had to be oriented with an angle of about 30° to the substrate surface. The IR spectra suggested that the complexation took place between aluminium ions and the oxygen atoms of the ligand rather than the nitrogen atom.     

稀土螯合物发光体LB膜的研究(I)

稀土有机配合物的发光研究近年来取得了可喜的近展.铕(Ⅲ)、铽(Ⅲ)、钐(Ⅲ)与β-二酮(β-dik),三正辛基氧化膦(TOPO)所形成的螯合物,以及它们的硝酸盐与邻菲咯啉(Phen)所形成的螯合物都是高光效的发光体,有广阔的应用前景,在某些方面已获得应用.如能把这些具有发光功能的稀土螯合物组装成有序的分子组合体,则很可能在分子光学技术,光电子技术等领域发挥重要作用.如何组装?本文用LB 膜技术,通过交替成膜或混     

导电聚合物LB膜

本文回顾了ＬＢ膜技术在导电聚合物体系中的利用，内容涉及共轭型导电聚合物（包括聚吡咯、聚噻吩、聚对亚苯基亚乙烯基、聚苯胺及其衍生物）ＬＢ膜的制备、结构表征、电导率与分子结构和分子堆砌之间的关系以及其他导电聚合物ＬＢ膜的研究现状。     

Preparation of copper sulphide clusters in organic-inorganic composites of Langmuir-Blodgett films of amphiphilic Schiff bases

Copper sulphide clusters were prepared in Langmuir-Blodgett films of copper complexes of amphiphilic Schiff bases-3,4-dimethoxy-N-benzylidene hexadeylamine (I) and 3,4-dimethoxy-N-benzylidene-4’-(hexadecylamino) benzylamine (II) The clusters obtained were analysed using UV-Vis spectroscopy and optical microscopy. Brewster angle microscopic studies on monolayers ofI andII at air/water interface showed formation of needle-like domains which seem to cluster faster inI than inII. Atomic force microscopy (AFM) studies also showed fairly uniform sized clusters inII whereas in the case ofI they seem to show varying sizes. From the results it is concluded that π-elongation in the polar head groups leads to controlled cluster sizes in compoundII as compared to those in compoundI.     

Alternating Langmuir-Blodgett Films with Interlayer Molecular Recognition

Alternating Langmuir-Blodgett films were successfully deposited with two complementary molecular components: a liglu-active barbituric acid derivative (B) and a melamine derivative (M). X-ray diffraction measurements show that the alternating films have a layered structure of HMBM…BM. The effect of the interlayer molecular recognition between B and M in the alternating films was observed via atomic force microscopic measurements.     

席夫碱及其络合物的可逆热致变色材料

对具有可逆的热致变色的席夫碱及其络合物的分类、合成、变色机理以及发展前景等进行了回顾和探讨。     

含酰基吡唑啉酮和咔唑光功能基元的新型席夫碱的合成

以苯肼、乙酰乙酸乙酯和咔唑为原料,合成了一种含酰基吡唑啉酮和咔唑双光功能基元的新型席夫碱———1-苯基-3-甲基-4-苯甲酰基-吡唑啉酮-5缩N-对氨基苄基咔唑(6),其结构经1H NMR和IR确证;采用UV-vis对其电子结构进行了初步研究,与酰基吡唑啉酮或咔唑功能基元相比,6表现出特殊的电子结构。     

四硫富瓦烯衍生物/硬脂酸LB膜的导电性研究

报导了14种四硫富瓦烯衍生物／硬脂酸LB膜的导电性，并解释了硬脂酸量和碘蒸气掺杂对LB膜导电性的影响．