Morphology controllable conjugated network polymers based on AIE-active building block for TNP detection

Luminescent conjugated network polymer is one of the most promising chemo-sensors owing to their good chemical/optical stability and multiple functionalization.Herein,three conjugated network polymers were prepared by using aggregation-induced emission active 1,1,2,2-tetrakis(4-formyl-(1,1'-biphenyl))-ethane(TFBE) unit as monomer and hydrazine as linker.Through regulating the synthetical condition,the polyme ric network can form either unifo rm two-dimensional azine-linked nanosheets(ANS),conjugated microporous polymers(A-CMP) or covalent organic frameworks(A-COF).All of these polymers exhibited good stability and high fluorescence quantum efficiency with the quantum yield of6.31% for A-NS,5.26% for A-CMP,and 5.80% for A-COF,as well as fast and selective fluorescence quenching response to 2,4,6-trinitrophenol(TNP).And the best TNP sensing performance with the Stern-Volmer constants(K_(sv)) values up to 8 × 10~5 L/mol and a detection limit of 0.09 μmol/L was obtained for A-NS.The study explores various strategies to construct conjugated polymers with different nanoarchitectures based on the same building block for sensitive detection of explosives.     

金纳米粒子的制备及在汞离子检测中的应用——推荐一个分析化学综合实验

Gold nanoparticles (Au NPs) were synthesized by reducing HAuCl₄ with sodium citrate. The sensitivity and selectivity of gold amalgam catalytic degradation of rhodamine B (RhB) system for mercury detection were investigated by fluorescence spectroscopy and ultraviolet-visible absorption spectroscopy. In the experiment, students' interest in scientific research and exploratory spirit will be stimulated, students' comprehensive experimental operation skills and subjective initiative will be improved, the understanding and application of nanoparticles preparation, characterization, catalytic reaction knowledge and metal ion analysis methods will be enhanced. Furthermore, the innovative thinking and scientific spirit of the students will be cultivated.     

Tb-MOFs在荧光检测方面的研究进展

镧系离子特殊的电子排布使镧系有机骨架材料（Ln-MOFs）具有独特的发光性质,通过骨架和不同客体分子间的相互作用,可实现对诸多物质的荧光检测。其中,以铽离子（Tb3+）为中心构筑的Tb-MOFs具有更优良的光学性能和更高的检测灵敏度,是一种极具潜力的高效荧光探针。本文以稀土Tb3+为主线,综述了近年来国内外Tb-MOFs材料在阴阳离子、有机小分子、生物分子荧光检测方面的研究进展,并对未来发展趋势进行了展望。     

食品中7种常见的非食用色素检测研究进展

食用色素可以明显的改善食品外观,激发食欲,在食品行业有着广泛的应用,但一些不法分子为了牟取暴利向食品中添加非食用色素来代替食用色素,但是非食用色素对人体存在致癌风险。食品中常见的非食用色素有以下7种：碱性嫩黄O、碱性橙II、酸性橙II、苏丹红、罗丹明B、美术绿和孔雀石绿,而目前对这7种非食用色素的检测还未全部建立国家标准。本文综述了近3年来食品行业中针对这7种非食用色素的各种检验方法,以期为食品安全监督监督检测机构提供参考。     

Determination of thallium in water samples

This article illustrates the developments of effective preconcentration techniques and highly sensitive detection methods for accurate measurements of Tl species at extremely low concentration in aqueous solutions. The literature on this topic was taken from the Analytical Abstracts in the period 1990-2005.     

Optimal filter design subject to output sidelobe constraints: Computational algorithm and numerical results

An algorithm is presented for the design of optimal detection filters in radar and communications systems, subject to inequality constraints on the maximum output sidelobe levels. This problem was reduced in an earlier paper (Ref. 1) to an unconstrained one in the dual space of regular Borel measures, with a nondifferentiable cost functional. Here, the dual problem is solved via steepest descent, using the directional Gateaux differential. The algorithm is shown to be convergent, and numerical results are presented.This research was supported by the Australian Research Grants Committee.     

Assembly of sugars on polystyrene plates: a new facile microarray fabrication technique

The work presented herein is a new noncovalent glycoarray assembly method for microplates created by simply mixing together an isocyanate-containing C₁₄-hydrocarbon and an amine-containing carbohydrate. 2-Aminoethyl-β-d-galactopyranoside (1) was utilized in model studies and product formation was detected by both ESI-MS and lectin binding. The method has been further extended to array complex carbohydrates.     

Multiple-detector responses or multiple-retention times: what is more informative for gas chromatography peak identification?

Multiple-separation and -detection are two approaches applied at the identification of analytes in chromatography. Using them depends on the physico-chemical properties and elemental content of the analytes. When physico-chemical properties are similar multiple-separation gives better opportunities for the identification. In this case, the efficiency of the columns is very important. When analytes contain some characteristic groups as--NO2, halogen, or nitrogen atoms then multiple-detection will be more useful. The sensitivity and/or selectivity of the detectors increase reliability of identification significantly.     

ATPases as Multi-Response Sensing System for Various Organic and Inorganic Analytes

Summary. The possibility of using synaptic plasma membrane (SPM) enzymes Na⁺/K⁺-ATPase and Mg²⁺-ATPase, isolated from rat brain, as a biological component of multi-response sensing system for detection of different compounds (alkaline and heavy metal salts, organic compounds) was studied. The method is based on the spectrophotometric determination of inorganic ortho-phosphate (P_i) that serves as a measure of the enzymatic activity in the presence of various analytes. The concentration of P_i, liberated by enzyme catalysed hydrolysis of adenosinetriphosphate (ATP), was followed spectrophotometrically, by single exposure to analytes or in the mixture. P_i was dose dependent on the analyte concentration. Alkaline elements (Na, K, Mg), heavy metals (Pb, Cd, Hg, Cu, Fe, Co, Zn), toxic organic compounds (pyridine, urea, chlorpyrifos), and some drugs (digoxin, gitoxin) showed diverse effects, inducing the inhibition or stimulation of the enzymes activity. Development of simple test method for simultaneous detection of the investigated analytes based on the variation of medium assay composition was discussed.