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A series of gallic acid =3,4,5trihydroxybenzoic acid; GA imprinted polymers were prepared in MeOH by noncovalent imprint technology. Their recognition properties and selectivity were characterized by equilibrium binding experiments. The recognition mechanism of the optimum imprinted polymer MIP3which was prepared with the molar ratio 4VP =4vinylpyridine=4ethenylpyridineGA 4 : 1, was explored by UV spectroscopy, Scatchardbindingmodel analysis, as well as structurerelevant binding. The obtained data consistently indicated that the recognition by MIP3was mainly based on the ionic interaction between the COOH group of GA and the pyridine moiety fixed on the matrix of the polymer. MIP3showed the maximum specific affinity to GA in H2OMeOH 1 : 1 vv at an apparent pH of 4.7 imprinting factor 18.6. Due to the high imprinting efficacy, the optimum polymer MIP3can effectively recognize GA in a complex mixture and possesses certainly an important application potential. [ABSTRACT FROM AUTHOR]

Three copper iodide coordination polymer (CuI-p-DPA) isomers were prepared from the fluorescent organic ligand p-DPA and cuprous iodide (CuI) under different solvothermal conditions, which exhibited quenched fluorescence behaviors after forming coordination polymers (CPs). These CuI-p-DPA isomers showed discrepant fluorescence responses to thiophanate-methyl (TM). Among these CuI-p-DPA isomers, α-CuI-p-DPA exhibited the maximum fluorescence enhancement after its incubation with TM in aqueous solution. The fluorescence enhancement mechanism was that TM competed with the ligand p-DPA to coordinate with CuI clusters, and then α-CuI-p-DPA released p-DPA into the solution and induced fluorescence enhancement. The present detection method possesses the advantages of good selectivity, high sensitivity, short response time, and strong anti-interference ability with a linear range of 0.5–100 μM and a detection limit of 0.01 μM. This study not only reveals that the spatial structures of CPs play an important role in the fluorescence response ability, but also provide a new fluorescence signal-on analysis method to rapidly and sensitively determine the pesticide residue for TM. [ABSTRACT FROM AUTHOR]

The pyrolysis behavior of Ni─Ca‐loaded Yunnan brown coals (Shi Caoxing [SCX] and Guo Jiashan [GJS]) was studied in a fixed‐bed reactor to investigate the effects of Ni, Ca, and Ni─Ca loading on the yields of the obtained liquids and light aromatic hydrocarbons. Structural variations of the prepared coal chars were characterized by the scanning electron microscope–energy dispersion X‐ray, Fourier‐transform infrared spectroscopy, X‐ray diffractometer, Brunauer–Emmett–Teller analysis, and elemental analysis. The effects of the Ni, Ca, and Ni─Ca loadings on the tar yield and upgradation of pyrolysis tar were evaluated. The results revealed that the use of the Ni─Ca catalyst affords improved yields of the liquid products and tar. Furthermore, the light hydrocarbon liquids contents in the coal tar was improved with the use of the Ni─Ca catalyst. The heavy components and polycyclic aromatic hydrocarbons in the coal tar could be easy to convert into light hydrocarbon liquids (phenol, cresol, xylenols, and naphthalene) with the SCX brown coal pyrolysis. In contrast, the catalytic pyrolysis of GJS brown coal was inhibited by the Ni─Ca catalyst. The study revealed that the catalytic activity of the Ni─Ca catalyst greatly depends on the type of the coal substrate and was promoted or inhibited depending on the type of the brown coal. Highlights: The content of light aromatic hydrocarbons is improved by Ni─Ca catalyst.The Ca promoter reacted with ash (S and Al) to form CaSO4, and CaAl4O7 compounds.Phenols are the main components in the light aromatic hydrocarbons.The catalytic activity of the Ni─Ca catalyst promoted or inhibited by coal rank. [ABSTRACT FROM AUTHOR]