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Lu L.,Shandong University | Wu J.,Shandong University | Song D.,Sino Biological | Zhao H.,Weifang Entry Exit Inspection and Quarantine Bureau | And 4 more authors.
Bioresource Technology | Year: 2013

A yeast strain (XS1) capable of selective utilization of fructooligosaccharides (FOSs) syrup was identified as Wickerhamomyces anomala. Cells of W. anomala XS1 were immobilized in calcium alginate and incubated with an FOS mixture at 30. °C. The purity of the FOS increased from 54.4% to 80.1% (w/w) as 93.6% of monosaccharides were metabolized while the oligosaccharides were not affected. The immobilized yeast cells could be recycled 10. times and the corresponding batch treatments achieved FOS purities around 80%. Thus, the method could be promising for large-scale purification of FOS syrup at low cost. A byproduct formed by the yeast was identified as ethyl β-d-fructofuranoside by MS and NMR spectroscopy. © 2012 Elsevier Ltd. Source

Guo F.,Shandong University | Li J.-J.,Weifang Entry Exit Inspection and Quarantine Bureau | Zhu B.-Y.,Shandong University | Zhang X.-L.,Shandong University
Synthesis and Reactivity in Inorganic, Metal-Organic and Nano-Metal Chemistry | Year: 2012

Two new coordination polymers [Ni(2,4'-oba)(1,10-phen)] n (1) and {[Ni(2,4'-Hoba) 2 (4,4'-bipy)(H 2O) 2]2H 2O} n(2) have been synthesized [2,4-H 2oba=2-(4- carboxyphenoxy)benzoic acid, 1,10-phen=1,10-phenanthroline and 4,4'-bipy=4,4-bipyridine]. The framework structures of these polymeric complexes have been determined by single-crystal X-ray diffraction studies. Complex 1 exhibits double-helical chains formed by π-π stacking interactions from the phenyl rings of the 1,10-phen ligands. Complex 2 forms a two-dimensional supramolecular architecture directed by hydrogen bonding. In compounds 1 and 2, the oba 2 ligands exhibit two coordination modes to link metal ions: bidentate chelating and monodenate modes. Copyright © Taylor & Francis Group, LLC. Source

Li H.,CAS Research Center for Eco Environmental Sciences | Zhang Q.,CAS Research Center for Eco Environmental Sciences | Wang P.,CAS Research Center for Eco Environmental Sciences | Li Y.,CAS Research Center for Eco Environmental Sciences | And 6 more authors.
Journal of Environmental Monitoring | Year: 2012

A total of 55 samples including soil, sediment, plants (cypress, reed and seepweed) and aquatic species were collected at locations around hexabromocyclododecane (HBCD) manufacturing facilities in Laizhou Bay area, East China. HBCD was determined at concentrations ranging between 0.88 and 6901 ng g-1 dry weight (dw), 2.93-1029 ng g-1 dw, 8.88-160241 ng g-1 dw, and 7.09-815 ng g-1 lipid weight (lw), respectively. Significant negative correlations (r2 = 0.54, p = 0.006) were observed between HBCD concentrations in soils and the distance from the manufacturing facility, and the concentrations became constant when the distance was >4 km. The calculation results on the bioaccumulation factors (BAFs) suggested that HBCD may be accumulated in plants. Tissue-specific bioaccumulation of HBCD diastereoisomers was found in aquatic species. For example, in crabs the highest concentrations of HBCD (815 ng g-1 lw for female and 446 ng g-1 lw for male) were observed in the gill. Besides the gill, α-HBCD was more preferentially accumulated in the spermary and ovary, while β- and γ-HBCD were more accumulated in the muscle. A similar distribution was also observed in roe and muscle of goby fish. © 2012 The Royal Society of Chemistry. Source

Dong J.,Weifang Entry Exit Inspection and Quarantine Bureau | Pan Y.,Weifang Entry Exit Inspection and Quarantine Bureau | Qin Y.,Beijing Micromole Separation Testing Technology Co. | Lu J.,Weifang Entry Exit Inspection and Quarantine Bureau | Yu Q.,Wuhan University
Chinese Journal of Chromatography (Se Pu) | Year: 2010

A gas chromatography-mass spectrometric (GC-M S) method has been established forth esimultaneous determination of 103 pesticide residues in cabbages and apples using programmable temperature vaporizer-based large volume injection (PTV-LV I) and negative chemical ionization (NCI). It was found that much lower detection limits for the investigated pesticides can be obtained. Prior to GC-NCI/MS analysis, the optimized parameters of PTV-LVI were as follows : inlet temperature was set at 45°C, split vent flow rate was 20 mL /min, evaporation time was 1 min and evaporation temperature was set at 60°C. The volume of injection was 10μL. Co-extractives were removedfrom the acetonitrile extracts using solid phase extraction with octadecyl (200 m g) and primary secondary amine (100 mg) sorbents. Matrix matched calibration solutions were used for all the analyses. To evaluate performance of the method, validation experiments were carried out in cabbages and apples at two spiking levels (5 and 10μg/k g). The average recoveries ranged from 58.5% to 113.2%, and the relative standard deviations (RSDs, n = 6) were in the range of 3.3% - 14.5%. The limits of detection (S/N = 3) were less than 5μg/kg for all the pesticides. The results show that this method is simple, rapid, sensitive and specific. It is appropriate for the simultaneous identification and quantification of the multi-residues in cabbages and apples. Source

Ding K.,Weifang Entry Exit Inspection and Quarantine Bureau | Xu W.,Weifang Entry Exit Inspection and Quarantine Bureau | Li K.,Weifang Entry Exit Inspection and Quarantine Bureau | Guo L.,Weifang Entry Exit Inspection and Quarantine Bureau | Sun J.,Weifang Entry Exit Inspection and Quarantine Bureau
Chinese Journal of Chromatography (Se Pu) | Year: 2016

A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for the study of dynamic behavior of aldicarb and its metabolite residues in cabbage. Aldicarb was applied onto cultivated cabbages. The pesticides concentrations were measured periodically (between application and harvest), and modeled to illustrate the dynamic behavior. The results showed that the liner ranges of aldicarb and its metabolites were from 0.005 to 0.2 mg/L, and the recoveries ranged from 78.9% to 108.5% with the relative standard deviations of 2.03% -8.91% (n = 8). The aldicarb in cabbage increased at first with the first-order kinetic equation model of c =0.020e0.136t with the correlation coefficient (r2) of 0.888, and then decreased with the equation of c =0.65e-0.059t with the r2 of 0.979 and the half-life of 29.1 d. The reducing processes of aldicarb-sulfone and aldicarb-sulfoxide both matched the first-order kinetic equations (c =23.4e-0.044t and c =4.54e-0.027t) with r2 of 0.916 and 0.972 respectively. To meet the limitation requirement of 0.01 mg/kg, 70.7, 226.6 and 176.3 d were respectively necessary for aldicarb, aldicarb-sulfone and aldicarb-sulfoxide. Final residues of aldicarb-sulfone and aldicarb-sulfoxide were still more than the limitation requirements, indicating that aldicarb should not be used in vegetables of growth cycle shorter than 120 d. This study provided theoretical basis for dynamic behavior of aldicarb residue and its safe use in vegetables. Source

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