基于4-(2,4-二羧基苯氧基)邻苯二甲酸配体的锌配位聚合物的合成、结构及其荧光传感性能

基于H₄dpa和bpy(H₄dpa=4-(2,4-二羧基苯氧基)邻苯二甲酸,bpy=4,4''-联吡啶)为配体,在水热条件下设计、合成了金属锌配位聚合物(Zn-CP)[Zn(H₂dpa)(bpy)_1.5]_n (1),并用元素分析、红外光谱、X射线单晶衍射等对其进行了结构表征。在1中相邻Zn²⁺与H₂dpa^2-离子和bpy配位形成的一维双链结构,相邻的一维双链通过氢键作用扩展形成三维超分子网结构。荧光研究表明:1是一种灵敏度高、选择性好、多响应的荧光传感器,可用于农药和硝基爆炸物的检测。有趣的是,2,4,6-三硝基苯(TNP)和嘧霉胺(Pth)对1的荧光发射显示出明显的猝灭效果,而抑霉唑(Ima)对1有荧光增强效果。此外,通过紫外可见吸收光谱、荧光寿命以及X射线光电子能谱探究了1的荧光传感机理。     

基于4-(2，4-二羧基苯氧基)邻苯二甲酸配体的锌配位聚合物的合成、结构及其荧光传感性能

基于H₄dpa和bpy (H₄dpa=4-(2,4-二羧基苯氧基)邻苯二甲酸,bpy=4,4''-联吡啶)为配体,在水热条件下设计、合成了金属锌配位聚合物(Zn-CP)[Zn(H₂dpa)(bpy)_1.5]_n (1),并用元素分析、红外光谱、X射线单晶衍射等对其进行了结构表征。在1中相邻Zn²⁺与H₂dpa^2-离子和bpy配位形成一维双链结构,相邻的一维双链通过氢键作用扩展形成三维超分子网结构。荧光研究表明：1是一种灵敏度高、选择性好、多响应的荧光传感器,可用于农药和硝基爆炸物的检测。有趣的是,2,4,6-三硝基苯(TNP)和嘧霉胺(Pth)对1的荧光发射显示出明显的猝灭效果,而抑霉唑(Ima)对1有荧光增强效果。此外,通过紫外可见吸收光谱、荧光寿命以及X射线光电子能谱探究了1的荧光传感机理。     

Spectrum Analysis of the Colored Pottery Figurines from Yangling Tombs of the Han Dynasty

ABSTRACT

The analysis of the colored pottery figurines from Yangling Tombs of the Han Dynasty was realized by X-ray diffraction, emission spectroscopy, infrared spectroscopy, X-ray fluorescence and fiber optics reflectance spectroscopy (FORS). Consequent results showed that the colored components were respectively mercuric(II) sulphide, ferric (III) oxide, and carbon, among which mercuric(II) sulphide was an artificial pigment.     

Nondestructive Synchrotron Radiation X-Ray Fluorescence Imaging of Trace Elements on Methylmercury and Selenium Administered Guinea Pigs

Abstract

The dynamics of the brain distributions of Hg, Zn, Cu and Se in guinea pigs exposed to methylmercury and selenium were examined by X-ray fluorescence imaging utilizing synchrotron radiation.

Male Hartley guinea pigs were administered methyl mercury chloride and/or sodium selenite every day for ten days (s.c. 3mg as Hg/kg/day, mole ratio Hg:Se=1:1). Two dimensional distributions of Hg, Zn, Cu and Se in guinea pig brain were observed by nondestructive X-ray fluorescence imaging. Using the     

Hydrothermal synthesis,structure and properties of a heteronuclear Co(III)–Ag(I) complex with the 2,6-pyridine-dicarboxlate

A new Ag/Co coordination polymer, [AgCo(PDC)₂] (1) (H₂PDC?=?2,6-pyridine-dicarboxylic acid) was synthesized under hydrothermal condition. X-ray crystallographic study reveals that 1 is a 2D network and has a previously unexplored coordination mode. Solid state fluorescence and thermogravimetric analysis (TGA) have been performed.     

Detection of Casting Material on Historical Violins by Infrared Spectroscopy and Total Reflection X-Ray Fluorescence Spectrometry

Abstract

Infrared spectroscopy and total reflection X-ray fluorescence spectrometry are used for the analysis of historical varnishes. Total reflection X-ray fluorescence spectrometry is used in the analysis of the elemental composition; infrared spectroscopy is used to determine the inorganic and organic molecules of the binding media, pigments and additives. On historical violins made by A. Guarneri and L. Widhalm silicon and tin were found by total reflection X-ray fluorescence spectrometry. Silicon was proved to be present in the form of silicon rubber by infrared spectroscopy. A further experiment confirmed that the treatment of a violin with silicon rubber casting material is detectable.     

Continuous X-ray fluorescence analysis of iron ore mixtures in the production of agglomerate

A system is developed for the continuous control of the chemical composition of iron ore mixtures (IOMs) by X-ray fluorescence analysis (XRF) directly on the conveyor belt. The system was found to be efficient under the conditions of mining and smelting production at the Magnitogorsk Metallurgical Combine. The proposed XRF method does not require sampling; provides the required accuracy; and offers advantages over other methods of analysis in terms of rapidity, cost, and productivity. The introduction of the system with an energy dispersive X-ray fluorescence spectrometer has improved the reliability of the operative control of the chemical composition of IOMs.     

Hydrogen bonding or deprotonation: on fluoride ion fluorescence sensing with 1,1′-bi-2-naphthol derivatives

The isolation and structural characterisation of two ionic complexes (S)-3 and(S)-4 based on fluoride ion-mediated deprotonation of 1,1′-bi-2-naphthol (BINOL) derivatives (S)-1 and (S)-2 have been carried out for the first time. X-ray crystallographic study showed that the deprotonated forms (S)-3 and (S)-4 adopt remarkably different molecular geometries, bond parameters as well as molecular packing modes from their neutral analogs, in agreement with their significant fluorescence changes upon the addition of fluoride ion, giving insights into the actual mechanism of fluoride ion fluorescence sensing. The deprotonation–protonation processes in two BINOL derivatives were also investigated by both fluorescence measurements and X-ray structural analyses. Such chiral basic compounds can be promising organocatalysts for asymmetric reactions.     

Application of the Sulfuric Acid-Halide Salt Reaction to the Analysis of Sulfuric Acid Containing Aerosols

Abstract

A new X-ray fluorescence method for the determination of sulfuric acid in sulfuric acid containing aerosols is presented. The technique makes use of the reaction between sulfuric acid and potassium chloride yielding volatile hydrogen chloride and thus changing the C1/K ratio. Nuclepore^R membrane filters are first loaded with potassium chloride and then used for the collection of the aerosol under study. The chlorine and potassium X-ray signals are measured before and after the sampling of the acid aerosol, and the decrease in the Cl/K intensity ratio is taken as a measure for the amount of sulfuric acid collected.     

GC-MS Analysis of Organic Vapours Emitted from Polyurethane Foam Insulation

Abstract

The vapours emitted by rigid polyurethane foam at 40° and 80° in dry and in humid (90% RH) air were trapped with a Tenax TA sampling tube and, after thermal desorption, analyzed by high resolution gas chromatography – mass spectrometry. The chromatograms obtained demonstrate a certain characteristic pattern. The qualitative composition of the effluent mixture is basically independent of both temperature and humidity of the foam. Over seventy compounds were identified as polyurethane foam off-gases. Among them the most numerous are hydrocarbons. The most abundant is the blowing agent, trichlorofluoromethane. The most interesting are cyclic acetals, aldehydes, cyclic ethers, alcohols, chloroform and chlorobenzene. The headspace concentration of the majority of them is below 10mg/m³, there are, however, several compounds with the concentration exceeding 100mg/m³.     

Structure,fluorescence, and carbon dioxide capture of a carboxylate cadmium complex

A new cadmium complex, [Cd₂(dcpa)·2H₂O]_n·H₂O (1), has been synthesized by hydrothermal reaction based on the multiple acid ligand 4-(2,5-dicarboxyphenoxy)phthalic acid (H₄dcpa). Single crystal X-ray diffraction analysis reveals that 1 is a three-dimensional structure with pores. The fluorescence test results show that the complex has excellent blue fluorescence. The adsorption of nitrogen and carbon dioxide gas test results show that the complex has adsorption effects on carbon dioxide.     

Synthesis,crystal structure and complexation behaviour of a thiacalix[4]arene bearing 1,2,3-triazole groups

The structure and complexation behaviour of 1,3-alternate-1,2,3-triazole based on thiacalix[4]arene,1,3-alternate-1 and 2 have been determined by means of X-ray analysis, fluorescence and ¹H NMR spectroscopy. The X-ray results suggested that the nitrogen atom N3 on triazole ring can act as hydrogen bond acceptors in the self-assembly of a supramolecular structure. The fluorescence spectra changes indicated that the thiacalix[4]arene bearing 1,2,3-triazole groups were highly selective for Ag⁺ in comparison with other tested metal ions by enhancement of the monomer emission of pyrene. The ¹H NMR results suggested that Ag⁺ can be strongly bonded by the triazole groups with the cooperation of the ionophoric cavity formed by the two inverted benzene rings and the sulfur atoms of the thiacalix[4]arene.     

一种用于选择性检测苯乙烯的Zn-MOFs发光传感器

在溶剂热条件下合成了一种新型金属有机框架（MOF）{[Zn₂（tyia）₂（H₂O）₂]·H₂O}_n（1）,其中H₂tyia为5-（1H-1,2,4-三唑-1-基）间苯二甲酸。运用X射线单晶衍射分析其结构,通过元素分析、粉末X射线衍射、热重分析、固体荧光分析等手段对配合物1进行表征,研究了其与有机小分子相互作用的荧光特性。结果表明其能够对低浓度苯乙烯迅速做出反应,最低识别浓度为1.06 mmol·L^-1。此外,还对其传感机制进行了研究。     

pitfalls in Using Filter Paper Disks as Standard Supports In X-Ray Fluorescence Spectrometry

Abstract

Standard solutions of dimethylarsinic acid in water and methanol are deposited on Whatman No. 1 and No. 114 filter papers. The arsenic content is measured by X-ray fluorescence spectrometry. The observed specific count depends on the nature of solvents, the volume of spotting solutions, the method of spotting and the type of filter papers.     

Adsorption of heavy metals by layered double hydroxides grown in situ on Al foam

We investigated the adsorption of heavy metal ions on a nanostructured coating of zinc-aluminum layered double hydroxides (Zn-Al LDHs) grown on aluminum foam by one-step hydrothermal process. This approach aimed to increase the interactive surface and provide a more practical medium for removal of toxic heavy metals from aqueous media. The foam coated with LDH was characterized by using scanning electron microscopy and X-ray diffraction. After immersion in a copper-rich water solution, X-ray photoelectron spectroscopy demonstrated the occurrence of adsorbed copper on the LDH-coated foam with two oxidation states: particles of metallic copper Cu⁰ with oxidized surface Cu⁺¹. X-ray diffraction showed the presence of Cu⁺² in the LDH structure.     

Novel room-temperature perylene liquid crystals: synthesis of 1,7-dibrominated cholesterol–perylene bisimides with different ester-bridging chains and their mesomorphic properties

Three novel 1,7-dibrominated cholesterol–perylene liquid crystals 6a, 6b and 6c with different ester-bridging chains were designed and synthesised in yields of 30–40%. Their structures were characterised by FT-IR, ¹H NMR and HR-MS spectra. Their mesomorphic behaviours were studied by differential scanning calorimetry (DSC), polarising optical microscopy (POM) and X-ray diffraction (XRD). Compounds 6a, 6b and 6c exhibit hexagonal columnar liquid crystalline phase at room temperature. Their mesomorphic temperature ranges are as wide as 140–162°C. Their fluorescence spectra suggested that they possess good fluorescence properties in solution. The soft ester-bridging chains are more favourable for room-temperature mesophase and high fluorescence than the rigid ester-bridging chain.     

4-(3H)-喹唑酮Co(Ⅱ)、Ag(Ⅰ)配合物的合成、晶体结构、荧光和抗癌活性

以4(3H)-喹唑酮、Co(NO₃)₂·6H₂O、AgNO₃为原料,在相同物料比、溶剂和常温条件下,合成了配合物[Co(L)₂·(H₂O)₂·(NO₃)₂] (1)和[Ag(L)₂·(NO₃)] (2)(L=4-(3H)-喹唑酮).对其进行了X-射线单晶衍射表征和热重分析.X-射线单晶衍射分析表明,它们都属于三斜晶系,但1是六配位,2是三配位的.还测定了2的固体荧光和抗癌活性.配合物2的最大发射波长比配体红移了27 nm,其对NCI(人非小细胞肺癌细胞)有较好的抗癌作用.     

4-(3H)-喹唑酮Co(Ⅱ)、Ag(Ⅰ)配合物的合成、晶体结构、荧光和抗癌活性

以4(3H)-喹唑酮、Co(NO3)2·6H2O、Ag NO3为原料,在相同物料比、溶剂和常温条件下,合成了配合物[Co(L)2·(H2O)2·(NO3)2](1)和[Ag(L)2·(NO3)](2)(L=4-(3H)-喹唑酮)。对其进行了X-射线单晶衍射表征和热重分析。X-射线单晶衍射分析表明,它们都属于三斜晶系,但1是六配位,2是三配位的。还测定了2的固体荧光和抗癌活性。配合物2的最大发射波长比配体红移了27 nm,其对NCI(人非小细胞肺癌细胞)有较好的抗癌作用。     

基于衣康酸配体构筑的两个锌配合物的合成、结构和荧光性质

通过水热法合成了两种锌配位聚合物{[Zn(ic)(bip)]·2H₂O}n (1)和[Zn(ic)(bpe)]n (2)(H₂ic=衣康酸,bip=3,5-二(1-咪唑基)吡啶,bpe=1,2-二(4-吡啶基)乙烯),并通过X射线单晶衍射和元素分析对其结构进行了表征.配合物1和2均为含有一维金属-羧酸链的二维(4,4)格子层结构.此外,对它们的热重、粉末X射线衍射和固体荧光性能进行了考察.与配体bip相比,1的发射光谱发生了明显的蓝移(~78 nm),可能归因于配体到金属的电荷转移;2显示与游离的bpe配体相似的荧光性质,轻微的红移可能是因为与金属离子之间的配位作用导致的.     

基于多羧酸烟酸配体的镝、钬、铒和铥配合物的合成及荧光、磁学性质的表征

以5-(4-羧基苯氧基)烟酸配体(H₂cpna)和稀土金属离子Dy³⁺、Ho³⁺、Er³⁺和Tm³⁺为原料,采用水热法合成了4种稀土金属配合物[M(Hcpna)(cpna)(H₂O)₃]_n,其中M=Dy(1)、Ho (2)、Er (3)、Tm (4)。单晶X射线衍射分析表明配合物1、2、3和4为同构配合物,均为一维链状结构。通过红外、元素分析以及粉末X射线衍射对所得配合物进行了表征,同时对配合物的荧光和磁学性质开展了研究。荧光测试结果表明,配合物1～4的荧光强度均低于配体H2cpna的荧光强度。在2～300 K温度范围内1 kOe直流电场下测试了配合物1～4的磁性,结果表明配合物1、2、3和4的χ_mT值分别为14.04、14.15、11.08和6.83 cm³·mol^-1·K,与文献理论值相符合。