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We developed an efficient and environmentally friendly two-step tandem methodology for the synthesis of sugar-containing coumarin derivatives catalyzed by lipozyme TL IM from Thermomyces lanuginosus in continuous-flow microreactors. Compared to those observed for other methods, the salient features of this work including green reaction conditions, short residence time (50 min), and catalysts are more readily available and the biocatalysis reaction process is efficient and easy to control. This two-step tandem synthesis of coumarin derivatives using the continuous-flow technology is a proof of concept that opens the use of enzymatic microreactors in coumarin derivative biotransformations.

A fast and green protocol for the Michael addition of imidazoles to acrylates catalyzed by Lipozyme TL IM from Thermomyces lanuginosus in a continuous flow microreactor was developed. In contrast with existing methods, this method is simple (35 min), uses mild reaction conditions (45 °C) and is environmentally friendly. This enzymatic Michael addition performed in continuous flow microreactors is an innovation that may open up the use of enzymatic microreactors in imidazole analogue biotransformations.

Three crystalline forms of Al2O3 featuring rod-like fibers are synthesized, to perform the gaseous degradation of 1-chloronaphthalene (CN-1), a model compound. The degradation efficiency (DE) decreases as follows: micro/nano-γ-Al2O3 > micro/nano-η-Al2O3 > regular α-Al2O3. The high DE of 92.2% attained over γ-Al2O3 is attributed to its specific defective spinel structure, resulting in its large surface area and pore volume, large amounts of surface-adsorbed oxygen species, and Bronsted and Lewis acid sites. The degradation products, naphthalene and 1,4/1,6-dichloronaphthalene (DiCN), with yield ratios of 7.3–13.3, are detected, indicating the occurrence of hydrodechlorination and side chlorination reactions. 1,6-DiCN is believed to be the most favored DiCN isomer product based on the calculated ΔHr and ΔGr. However, the percentage values of intermediates formed via these two reactions, in the degradation of CN-1, are 9.1%, 4.5% and 4.4%, over α-, η- and γ-Al2O3, respectively. The oxidative degradation pathway possibly dominantly occurs especially over micro/nano-γ-Al2O3 with oxidative species such as O2−, O− and O2−, following the Mars–van Krevelen mechanism. Oxidation intermediates containing –CH2–, –CH3, and C–O groups are produced, which can be subsequently oxidized to low-molecular-weight products, such as formic, acetic and propanoic acids, and eventually completely oxidized to CO2.

Mesoporous face-centered-cubic (fcc) In4Ni alloy nanorices (NRs) were successfully synthesized as superior catalysts for N2H4 dehydrogenation in aqueous solution via a facile solution plasma technique (SPT) in an ionic liquid, 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][BF4]). This incorporation introduces basic sites for dehydrogenation. Also, the synthesis of In and Ni weakens the interactions among generated adspecies such as H2 and NHx and surface metal atoms. Alongside their unique NR structure, the as-prepared fcc-In4Ni alloy NRs exhibited superior performance for N2H4 dehydrogenation in aqueous solution. The activation energy of the fcc-In4Ni alloy NRs was 38.9 ± 1.0 kJ mol(-1). The NRs were also found to be stable for catalytic N2H4 dehydrogenation in aqueous solution, providing an average TOF value of 82.0 (mol of H2 (mol of active In4Ni min)(-1)) over 30 h reaction. These fcc-In4Ni alloy NRs have demonstrated exceptional performance, which indicates that the construction of hydrogen-producing systems from N2H4, capable of matching the performance of NaBH4 and NH3BH3 hydrogen-producing systems for fuel-cell applications, is a promising possibility.

Mesoporous face-centered-cubic (fcc) In4Ni alloy nanorices (NRs) were successfully synthesized as superior catalysts for N2H4 dehydrogenation in aqueous solution via a facile solution plasma technique (SPT) in an ionic liquid, 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][BF4]). This incorporation introduces basic sites for dehydrogenation. Also, the synthesis of In and Ni weakens the interactions among generated adspecies such as H2 and NHx and surface metal atoms. Alongside their unique NR structure, the as-prepared fcc-In4Ni alloy NRs exhibited superior performance for N2H4 dehydrogenation in aqueous solution. The activation energy of the fcc-In4Ni alloy NRs was 38.9 ± 1.0 kJ mol(-1). The NRs were also found to be stable for catalytic N2H4 dehydrogenation in aqueous solution, providing an average TOF value of 82.0 (mol of H2 (mol of active In4Ni min)(-1)) over 30 h reaction. These fcc-In4Ni alloy NRs have demonstrated exceptional performance, which indicates that the construction of hydrogen-producing systems from N2H4, capable of matching the performance of NaBH4 and NH3BH3 hydrogen-producing systems for fuel-cell applications, is a promising possibility.

An efficient method for the preparation of β-amino alcohols catalyzed by lipase TL IM from Thermomyces lanuginosus in a continuous-flow reactor was developed. The eco-friendly biocatalyst combined with continuous-flow reaction technology displayed high efficiency in the synthesis of β-amino alcohols. The benign reaction conditions (35 °C) and short residence time (20 min), together with the use of low cost and readily available starting materials, make this synthetic approach a promising alternative to current β-amino alcohol synthesis.

A continuous-flow procedure for the synthesis of β-amino acid esters has been developed via lipase-catalyzed Michael reaction of various aromatic amines with acrylates. Lipase TL IM from Thermomyces lanuginosus was first used to catalyze Michael addition reaction of aromatic amines. Compared with other methods, the salient features of this work include green reaction conditions (methanol as reaction medium), short residence time (30 min), readily available catalyst and a reaction process that is easy to control. This enzymatic synthesis of β-amino acid esters performed in continuous-flow microreactors is an innovation that provides a new strategy for the fast biotransformation of β-amino acid esters.

6.8 nm face-centered-cubic indium nanocubes were prepared via plasma-assisted hydrogen reduction in ionic liquid 1-butyl-3-methylimidazolium chloride and KClO4 as a {100}-facet director. The nanocubes exhibited excellent dehydrogenation activity toward aqueous hydrazine owing to their localized surface plasmon resonance.

Hollow amorphous NaFePO4 nanospheres were prepared on a large scale by a simple in situ hard template process, wherein the hollow nanospheres exhibited a high storage capacity and high rate as a cathode material for sodium-ion batteries.

Li9V3(P2O7)3(PO4)2 nanotubes were prepared on large scale by a simple molten salt route without the use of a surfactant as a template and the nanotubes exhibited excellent cycling stability in addition to enhanced rate capability as cathode materials for lithium-ion batteries.

A field experiment was conducted to evaluate clofentezine residue levels and dissipation trend in tangerine and soil for the safe application of clofentezine. A modified QuEChERS-HPLC-UVD method was developed to analyse clofentezine in tangerine and soil. Tangerine samples were homogenised and extracted by acetonitrile and then cleaned up with dispersive solid phase extraction (dSPE) by primary and secondary amine (PSA) and C18. Clofentezine residue was determined by high-performance liquid chromatography (HPLC) with a UV detector (UVD) at the wavelength of 268 nm. The presented method achieved the good linear relationship within the range from 0.05 to 5.0 mg kg−1 for clofentezine (R2 > 0.998). At the fortification levels of 0.05, 0.50 and 1.00 mg kg−1 in tangerine pulp, tangerine peel and soil, recoveries ranged from 75.9% to 117.7% with relative standard deviations (RSD) less than 8.2%. In the supervised field trials, the half-lives of clofentezine in tangerine and soil were approximately 11.3 and 8.6 d...

Hexabromocyclododecanes (HBCDs), a new type of persistent organic pollutants widely used as brominated flame retardants, have attracted wide attention due to their increasing level and toxicity. A method based on high-performance liquid chromatography mass spectrometry (HPLC-MS-MS) in electrospray ionization mode has been developed by optimization of various parameters, which effectively improved the separation degree and responsive intensity of α-, β- and γ-HBCD isomers. The concentrations and distribution profiles of three HBCD isomers were investigated in sediments from the Haihe River in China. It was observed that the concentrations of HBCDs varied in the range of 0.4-58.82ng/g, showing a decreasing trend along the flow direction, possibly due to attenuation and biodegradation along the flow direction of the Haihe River. The distribution profile of α-, β-, γ-HBCD was 7.91%-88.6%, 0-91.47%, and 0.62%-42.83%, respectively. Interestingly, α-HBCD dominated in most sample sites. This was different from the distribution profile in commercial industrial products, which might be attributed to the inter-transformation and different degradation rates of the three HBCD isomers. The potential ecological risk of HBCDs in sediment was characterized under the two-tiered procedure of the European Medicines Evaluation Agency for environmental risk assessment. Although the HBCDs in the selected section of the Haihe River presented "no risk" in the sediment compartment, its risk in sediment cannot be neglected since sediment is one of the important sinks and reservoirs of pollutants.

A novel copper-azido coordination polymer, [Cu2(N3)3(L)]n (1, HL=pyrazine-2-carboxylic acid), has been synthesized by hydrothermal reaction with “Non-innocent” reagent in the aqueous solution. In the reaction system, CuII ions are avoided to reduce to CuI ions due to the existence of NdIII. It is found that the complex is a 3D structure based on two double EO azido bridged trimmers and octahedron CuII ions, in which the azide ligands take on EO and μ1,1,3 mode to form CuII-azido 2D layers, furthermore L ligands pillar 2D layers into an infinite 3D framework with the Schlafli symbol of {4;62}4{42;612;810;104}{42;64}. Magnetic studies revealed that the interactions between the CuII ions in the trimmer are ferromagnetic for the Cu–N–Cu angle nearly 98°, while the interactions between the trimmer and octahedron CuII ion are antiferromgantic and result in an antiferromagnetic state.

Four isomorphous lanthanide complexes, [Ln2(L)6(H2O)2]·2H2O [Ln = Ce (1), Ln = Nd (2), Ln = Sm (3), Ln = Pr (4)] (HL = 4-Hydroxy-6-methylnicotinic acid) were synthesized by the reaction of nitrate salts of LnIII and HL by hydrothermal method, which were characterized by single-crystal X-ray diffraction, elemental analysis, FT-IR spectra, UV–vis spectra, TG analyses and X-ray powder diffraction (XRPD). The crystal structures of 1–4 consist of homodinuclear species, which bridged by two oxygen atoms from two L ligands. The photoluminescence properties of compounds 3 and 4 in the solid state at room temperature were investigated. The complex 3 is demonstrated orange–red luminescence, while the luminescence spectrum of complex 4 is typical for the praseodymium complexes.

Chlorophenols are structurally similar to PCDD/Fs and have been considered as highly potential precursors for PCDD/Fs formation. The suppressing effects of PCDD/F formation from pentachlorophenol (PCP) were investigated on various mass ratios of CaO and urea. The total concentration of 2,3,7,8-PCDD/Fs, mostly dominated by OCDD, was determined to be 48.58-10186ng/mg in inhibitor-reaction systems, being much lower than that in blank reaction system (75654ng/mg). Interestingly, compared with pure CaO and urea reaction system, the concentration and TEQ of formed 2,3,7,8-PCDD/Fs in mixed urea/CaO reaction system were lower, especially with 5-20% urea reaction systems being respectively at decrease by 96.5-99.4% and 99.2-99.7%. The suppression efficiency of TEQ in 5-20% urea reaction systems could be always approximately 100% under 250-350°C. These results suggested that mixed inhibitors, especially 5-20% urea inhibitors, have a synergetic inhibition effect for PCDD/Fs formation from PCP. Mixed inhibitor generated several intermediates, involving CO2, H2O, NH3, Ca(OH)2, CaCO3, HNCO, biuret and ammelide. The complex between PCP and Ca, N-doped species, lower chlorinated phenols and benzenediol, and organic acids were also determined. Synergetic inhibition mechanism may be attributed to accelerated facilitation of acid-base reaction and N doping. The decomposition of PCP itself also contributes to prevent PCDD/Fs formation.

A series of Fe-Al composite oxides were synthesized by the hydrothermal method using different urea dosages and examined towards the degradation of 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) at 300 °C. The as-prepared oxides were characterized by field-emission scanning electron microscopy, X-ray diffraction and energy-dispersive X-ray spectroscopy. The morphology and composition of the prepared materials could be regulated by controlling the urea concentration. Interestingly, these properties influenced the nature and amount of the hydrodebromination products generated during the degradation of BDE-47. The degradation of BDE-47 over the composite oxide prepared at a urea dosage of 3 mmol generated BDE-17 as the major isomer product, followed by BDE-28/33, -30, and -32, among the tribromodiphenyl ethers (tri-BDEs). Regarding the dibromodiphenyl ethers (di-BDEs) produced, the amount of the isomers decreased in the order of BDE-8/11 > BDE-7 > BDE-15 > BDE-10. And the BDE-1 among monobromodiphenyl was determined. In contrast, over the composite oxides prepared at urea dosages greater than 3 mmol, BDE-28/33 gradually become the major isomer product instead of BDE-17 among tri-BDEs. The amount of the other di-BDEs isomer such as BDE-15 and -10 approach to be comparable to that BDE-8/11. However, regardless of the urea dosage, BDE-47 converted into BDE-75 via an isomerization reaction. Based on these intermediate products identification, a possible hydrodebromination mechanism of BDE-47 over Fe-Al composite oxide was comprehensively traced.

Large scale preparation of Li9V3(P2O7)3 (PO4)2 nanotubes is performed by a simple molten salt route without the use of a surfactant as a template.

A rapid and simple HPLC-fluorescence detection method has been developed for the determination of abamectin residues in edible oil. Residues are extracted with acetonitrile and by vortexing and then directly derivatized with no need for a time-consuming cleanup step. Trifluoroacetic anhydride and N-methylimidazole were used as derivatizing agents of abamectin. Abamectin was detected and quantitated with fluorescence detection (excitation: 365 nm; emission: 475 nm), and methanol was used as the mobile phase. The LOD was 0.001 mg/kg and the LOQ was 0.003 mg/kg. The recoveriesranged from 86 to 100.4% with satisfactory precision (RSD < 10.1%). This method proved to be sensitive, environmentally friendly, time-saving, and efficient.

In this work, a rapid, environment friendly and sensitive method was established for the extraction and analysis of five organophosphorus pesticides (OPPs) (chlorpyrifos, chlorpyrifos-methyl, isocarbophos, malathion and phorate) in milk samples by means of gas chromatography-flame photometric detection. The pesticides were first extracted with acetonitrile from milk samples by using the modified "quick, easy, cheap, effective, rugged, and safe" (QuEChERS) method. No other clean-up was required after extraction. Then the above-mentioned acetonitrile extract was concentrated by using the dispersive liquid-liquid microextraction combined with solidification of floating organic droplets technique. Several factors that could influence the extraction efficiency, such as type of extraction solvent, disperser solvent, volume of extraction and disperser solvent, salt effect, sample pH, and extraction time, were investigated and optimized. As a result, 15 µL of 1-dodecanol were used as the extractant because of its lower toxicity, 300 µL methanol was chosen as dispersant and the extraction time was set to 1 min. Under the optimized conditions, good linearity was exhibited from 0.01 to 1.0 mg/L with the correlation coefficients higher than 0.9968. The limits of detection of the five OPPs were ranged in 0.1-0.3 μg/L, and the limits of quantification were at the range of 0.3-1.0 μg/L. Moreover, the recoveries of the target analytes from milk samples at spiking levels of 0.01, 0.05 and 0.1 mg/L were between 80.5 and 106.5% with the relative standard deviations varied from 3.6 to 6.3%. This method has been successfully applied to detect OPPs in real milk samples.

In the crystal structure of the binuclear title complex, [Co(N(3))(2)(C(12)H(8)N(2))](n), each Co(II) cation is coordinated by two N atoms from one chelating 1,10-phenanthroline ligand and four azide ligands in a slightly distorted octa-hedral coordination. The two Co(II) cations of the binuclear complex are related by an inversion centre and are bridged by two symmetry-related azide ligands in both μ(1,1) and μ(1,3) modes. The μ(1,3) bridging mode gives rise to an infinite one-dimensional chain along the a axis, whereas the μ(1,1) bridging mode is responsible for the formation of the binuclear Co(II) complex.