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Yongliang Zhao - One of the best experts on this subject based on the ideXlab platform.
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luminescence properties and crystal structure of europium complexes with Phenoxyacetic Acid and 2 4 6 tri 2 pyridyl s triazine
Journal of Luminescence, 2015Co-Authors: Ailing Wang, Xiaoyan Wei, Haixia Zhang, Zhongxia Wang, Haibin Chu, Dan Zhou, Yingnan Chen, Yongliang ZhaoAbstract:Abstract Using anion ligand Phenoxyacetic Acid (HPOA) and neutral ligand 2,4,6-tri(2-pyridyl)-s-triazine (TPTZ), two complexes Eu2(TPTZ)2(POA)6·6H2O and EuY(TPTZ)2(POA)6·6H2O have been synthesized and one crystal EuY(TPTZ)2(POA)6·2CH3OH has been obtained. These complexes are characterized by elemental analysis, ICP-AES, IR and UV absorption spectroscopy. The luminescence spectra, luminescence lifetimes and emission quantum efficiencies of the complexes have been studied. The results show that the complex EuY(TPTZ)2(POA)6·6H2O exhibits stronger luminescence intensity, longer luminescent lifetime and higher emission quantum efficiency than Eu2(TPTZ)2(POA)6·6H2O. The single-crystal X-ray diffraction of EuY(TPTZ)2(POA)6·2CH3OH reveals that the crystal is heteronuclear and crystallizes in the triclinic space group P-1 with following unit cell parameters a=12.2411(10) A, b=13.2294(11) A, c=13.5232(11) A, α=74.8596(13)°, β=82.9593(16)°, γ=87.1641(14)°, and V=2097.7(3) A3. Each metal ion coordinates with three nitrogen atoms of one TPTZ and seven oxygen atoms of three POA− ions. And there exist two coordination forms between POA− and metal ions in the crystal. One is chelating bidentate, the other is the single-atom bridge.
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crystal structure and photoluminescence of two europium compounds with Phenoxyacetic Acid and 2 4 6 tri 2 pyridyl s triazine
Dalton Transactions, 2014Co-Authors: Ailing Wang, Xiaoyan Wei, Haixia Zhang, Bin Yue, Jie Kang, Zhongxia Wang, Haibin Chu, Yongliang ZhaoAbstract:Two novel crystal compounds of Eu3+ and Gd3+/Eu3+ with Phenoxyacetic Acid (HPOA) and 2,4,6-tri(2-pyridyl)-s-triazine (TPTZ) have been synthesized. The two compounds are characterized by elemental analysis, rare earth coordination titrations, molar conductivity measurements, UV-vis absorption spectroscopy and IR spectroscopy. The crystal structures of compounds 1 Eu2(TPTZ)2(POA)6·2CH3OH and 2 EuGd(TPTZ)2(POA)6·2CH3OH were determined by single-crystal X-ray diffraction. The two monocrystals belong to the triclinic system and space group P with the following unit cell parameters: a = 12.2448(10), 12.2476(6) A; b = 13.2214(11), 13.2260(7) A; c = 13.5248(12), 13.5210(7) A; α = 74.8544(15), 74.8810(10)°; β = 83.0605(16), 83.0465(8)°; γ = 87.1996(14), 87.2126(8)°; V = 2097.7(7), 2098.5(19) A3 and Z = 1, respectively. They are both dinuclear: one is homonuclear and the other is heteronuclear. Each metal ion is coordinately bonded to three nitrogen atoms of one TPTZ and seven oxygen atoms of three phenoxyacetate ions. Furthermore, there exist two coordinate forms between C6H5OCH2COO− and metal ions. One is chelating bidentate and the other is chelating and bridge coordinating. The triplet energy level of Phenoxyacetic Acid was measured, which is approximately 22 500 cm−1, indicating that the lowest excitation state energy level of Eu(III) and the triplet state energy level of Phenoxyacetic Acid match well with each other. The luminescent emission intensity of both compounds was very strong. Besides, the results indicate that the luminescent emission intensity, luminescence lifetimes and the emission quantum efficiencies of Gd3+/Eu3+ compound 2 are remarkably superior to those of compound 1, respectively. This phenomenon may mainly result from the decrease of the concentration quenching effect of Eu3+ ions, and the intramolecular energy transfer from the ligands coordinated with Gd3+ ions to Eu3+ ions.
Martin Danaher - One of the best experts on this subject based on the ideXlab platform.
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determination and occurrence of Phenoxyacetic Acid herbicides and their transformation products in groundwater using ultra high performance liquid chromatography coupled to tandem mass spectrometry
Molecules, 2014Co-Authors: Sarahlouise Mcmanus, Mary Moloney, Karl G Richards, Catherine Coxon, Martin DanaherAbstract:A sensitive method was developed and validated for ten Phenoxyacetic Acid herbicides, six of their main transformation products (TPs) and two benzonitrile TPs in groundwater. The parent compounds mecoprop, mecoprop-p, 2,4-D, dicamba, MCPA, triclopyr, fluroxypr, bromoxynil, bentazone, and 2,3,6-trichlorobenzoic Acid (TBA) are included and a selection of their main TPs: Phenoxyacetic Acid (PAC), 2,4,5-trichloro-phenol (TCP), 4-chloro-2-methylphenol (4C2MP), 2,4-dichlorophenol (DCP), 3,5,6-trichloro-2- pyridinol (T2P), and 3,5-dibromo-4-hydroxybenzoic Acid (BrAC), as well as the dichlobenil TPs 2,6-dichlorobenzamide (BAM) and 3,5-dichlorobenzoic Acid (DBA) which have never before been determined in Irish groundwater. Water samples were analysed using an efficient ultra-high performance liquid chromatography (UHPLC) method in an 11.9 min separation time prior to detection by tandem mass spectrometry (MS/MS). The limit of detection (LOD) of the method ranged between 0.00008 and 0.0047 µg·L −1 for the 18 analytes. All compounds could be detected below the permitted limits of 0.1 µg·L −1 allowed
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Determination and Occurrence of Phenoxyacetic Acid Herbicides and Their Transformation Products in Groundwater Using Ultra High Performance Liquid Chromatography Coupled to Tandem Mass Spectrometry
MDPI AG, 2014Co-Authors: Sarahlouise Mcmanus, Mary Moloney, Karl G Richards, Catherine E. Coxon, Martin DanaherAbstract:A sensitive method was developed and validated for ten Phenoxyacetic Acid herbicides, six of their main transformation products (TPs) and two benzonitrile TPs in groundwater. The parent compounds mecoprop, mecoprop-p, 2,4-D, dicamba, MCPA, triclopyr, fluroxypr, bromoxynil, bentazone, and 2,3,6-trichlorobenzoic Acid (TBA) are included and a selection of their main TPs: Phenoxyacetic Acid (PAC), 2,4,5-trichloro-phenol (TCP), 4-chloro-2-methylphenol (4C2MP), 2,4-dichlorophenol (DCP), 3,5,6-trichloro-2-pyridinol (T2P), and 3,5-dibromo-4-hydroxybenzoic Acid (BrAC), as well as the dichlobenil TPs 2,6-dichlorobenzamide (BAM) and 3,5-dichlorobenzoic Acid (DBA) which have never before been determined in Irish groundwater. Water samples were analysed using an efficient ultra-high performance liquid chromatography (UHPLC) method in an 11.9 min separation time prior to detection by tandem mass spectrometry (MS/MS). The limit of detection (LOD) of the method ranged between 0.00008 and 0.0047 µg·L−1 for the 18 analytes. All compounds could be detected below the permitted limits of 0.1 µg·L−1 allowed in the European Union (EU) drinking water legislation [1]. The method was validated according to EU protocols laid out in SANCO/10232/2006 with recoveries ranging between 71% and 118% at the spiked concentration level of 0.06 µg·L−1. The method was successfully applied to 42 groundwater samples collected across several locations in Ireland in March 2012 to reveal that the TPs PAC and 4C2MP were detected just as often as their parent active ingredients (a.i.) in groundwater
Ailing Wang - One of the best experts on this subject based on the ideXlab platform.
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luminescence properties and crystal structure of europium complexes with Phenoxyacetic Acid and 2 4 6 tri 2 pyridyl s triazine
Journal of Luminescence, 2015Co-Authors: Ailing Wang, Xiaoyan Wei, Haixia Zhang, Zhongxia Wang, Haibin Chu, Dan Zhou, Yingnan Chen, Yongliang ZhaoAbstract:Abstract Using anion ligand Phenoxyacetic Acid (HPOA) and neutral ligand 2,4,6-tri(2-pyridyl)-s-triazine (TPTZ), two complexes Eu2(TPTZ)2(POA)6·6H2O and EuY(TPTZ)2(POA)6·6H2O have been synthesized and one crystal EuY(TPTZ)2(POA)6·2CH3OH has been obtained. These complexes are characterized by elemental analysis, ICP-AES, IR and UV absorption spectroscopy. The luminescence spectra, luminescence lifetimes and emission quantum efficiencies of the complexes have been studied. The results show that the complex EuY(TPTZ)2(POA)6·6H2O exhibits stronger luminescence intensity, longer luminescent lifetime and higher emission quantum efficiency than Eu2(TPTZ)2(POA)6·6H2O. The single-crystal X-ray diffraction of EuY(TPTZ)2(POA)6·2CH3OH reveals that the crystal is heteronuclear and crystallizes in the triclinic space group P-1 with following unit cell parameters a=12.2411(10) A, b=13.2294(11) A, c=13.5232(11) A, α=74.8596(13)°, β=82.9593(16)°, γ=87.1641(14)°, and V=2097.7(3) A3. Each metal ion coordinates with three nitrogen atoms of one TPTZ and seven oxygen atoms of three POA− ions. And there exist two coordination forms between POA− and metal ions in the crystal. One is chelating bidentate, the other is the single-atom bridge.
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crystal structure and photoluminescence of two europium compounds with Phenoxyacetic Acid and 2 4 6 tri 2 pyridyl s triazine
Dalton Transactions, 2014Co-Authors: Ailing Wang, Xiaoyan Wei, Haixia Zhang, Bin Yue, Jie Kang, Zhongxia Wang, Haibin Chu, Yongliang ZhaoAbstract:Two novel crystal compounds of Eu3+ and Gd3+/Eu3+ with Phenoxyacetic Acid (HPOA) and 2,4,6-tri(2-pyridyl)-s-triazine (TPTZ) have been synthesized. The two compounds are characterized by elemental analysis, rare earth coordination titrations, molar conductivity measurements, UV-vis absorption spectroscopy and IR spectroscopy. The crystal structures of compounds 1 Eu2(TPTZ)2(POA)6·2CH3OH and 2 EuGd(TPTZ)2(POA)6·2CH3OH were determined by single-crystal X-ray diffraction. The two monocrystals belong to the triclinic system and space group P with the following unit cell parameters: a = 12.2448(10), 12.2476(6) A; b = 13.2214(11), 13.2260(7) A; c = 13.5248(12), 13.5210(7) A; α = 74.8544(15), 74.8810(10)°; β = 83.0605(16), 83.0465(8)°; γ = 87.1996(14), 87.2126(8)°; V = 2097.7(7), 2098.5(19) A3 and Z = 1, respectively. They are both dinuclear: one is homonuclear and the other is heteronuclear. Each metal ion is coordinately bonded to three nitrogen atoms of one TPTZ and seven oxygen atoms of three phenoxyacetate ions. Furthermore, there exist two coordinate forms between C6H5OCH2COO− and metal ions. One is chelating bidentate and the other is chelating and bridge coordinating. The triplet energy level of Phenoxyacetic Acid was measured, which is approximately 22 500 cm−1, indicating that the lowest excitation state energy level of Eu(III) and the triplet state energy level of Phenoxyacetic Acid match well with each other. The luminescent emission intensity of both compounds was very strong. Besides, the results indicate that the luminescent emission intensity, luminescence lifetimes and the emission quantum efficiencies of Gd3+/Eu3+ compound 2 are remarkably superior to those of compound 1, respectively. This phenomenon may mainly result from the decrease of the concentration quenching effect of Eu3+ ions, and the intramolecular energy transfer from the ligands coordinated with Gd3+ ions to Eu3+ ions.
Sarahlouise Mcmanus - One of the best experts on this subject based on the ideXlab platform.
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determination and occurrence of Phenoxyacetic Acid herbicides and their transformation products in groundwater using ultra high performance liquid chromatography coupled to tandem mass spectrometry
Molecules, 2014Co-Authors: Sarahlouise Mcmanus, Mary Moloney, Karl G Richards, Catherine Coxon, Martin DanaherAbstract:A sensitive method was developed and validated for ten Phenoxyacetic Acid herbicides, six of their main transformation products (TPs) and two benzonitrile TPs in groundwater. The parent compounds mecoprop, mecoprop-p, 2,4-D, dicamba, MCPA, triclopyr, fluroxypr, bromoxynil, bentazone, and 2,3,6-trichlorobenzoic Acid (TBA) are included and a selection of their main TPs: Phenoxyacetic Acid (PAC), 2,4,5-trichloro-phenol (TCP), 4-chloro-2-methylphenol (4C2MP), 2,4-dichlorophenol (DCP), 3,5,6-trichloro-2- pyridinol (T2P), and 3,5-dibromo-4-hydroxybenzoic Acid (BrAC), as well as the dichlobenil TPs 2,6-dichlorobenzamide (BAM) and 3,5-dichlorobenzoic Acid (DBA) which have never before been determined in Irish groundwater. Water samples were analysed using an efficient ultra-high performance liquid chromatography (UHPLC) method in an 11.9 min separation time prior to detection by tandem mass spectrometry (MS/MS). The limit of detection (LOD) of the method ranged between 0.00008 and 0.0047 µg·L −1 for the 18 analytes. All compounds could be detected below the permitted limits of 0.1 µg·L −1 allowed
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Determination and Occurrence of Phenoxyacetic Acid Herbicides and Their Transformation Products in Groundwater Using Ultra High Performance Liquid Chromatography Coupled to Tandem Mass Spectrometry
MDPI AG, 2014Co-Authors: Sarahlouise Mcmanus, Mary Moloney, Karl G Richards, Catherine E. Coxon, Martin DanaherAbstract:A sensitive method was developed and validated for ten Phenoxyacetic Acid herbicides, six of their main transformation products (TPs) and two benzonitrile TPs in groundwater. The parent compounds mecoprop, mecoprop-p, 2,4-D, dicamba, MCPA, triclopyr, fluroxypr, bromoxynil, bentazone, and 2,3,6-trichlorobenzoic Acid (TBA) are included and a selection of their main TPs: Phenoxyacetic Acid (PAC), 2,4,5-trichloro-phenol (TCP), 4-chloro-2-methylphenol (4C2MP), 2,4-dichlorophenol (DCP), 3,5,6-trichloro-2-pyridinol (T2P), and 3,5-dibromo-4-hydroxybenzoic Acid (BrAC), as well as the dichlobenil TPs 2,6-dichlorobenzamide (BAM) and 3,5-dichlorobenzoic Acid (DBA) which have never before been determined in Irish groundwater. Water samples were analysed using an efficient ultra-high performance liquid chromatography (UHPLC) method in an 11.9 min separation time prior to detection by tandem mass spectrometry (MS/MS). The limit of detection (LOD) of the method ranged between 0.00008 and 0.0047 µg·L−1 for the 18 analytes. All compounds could be detected below the permitted limits of 0.1 µg·L−1 allowed in the European Union (EU) drinking water legislation [1]. The method was validated according to EU protocols laid out in SANCO/10232/2006 with recoveries ranging between 71% and 118% at the spiked concentration level of 0.06 µg·L−1. The method was successfully applied to 42 groundwater samples collected across several locations in Ireland in March 2012 to reveal that the TPs PAC and 4C2MP were detected just as often as their parent active ingredients (a.i.) in groundwater
Søren J. Sørensen - One of the best experts on this subject based on the ideXlab platform.
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Enhanced degradation of Phenoxyacetic Acid in soil by horizontal transfer of the tfdA gene encoding a 2,4-dichloroPhenoxyacetic Acid dioxygenase
FEMS microbiology ecology, 2001Co-Authors: Julia R. De Lipthay, Tamar Barkay, Søren J. SørensenAbstract:Few studies have investigated the possible impact of in situ gene transfer on the degradation of xenobiotic compounds in natural environments. In this work we showed that horizontal transfer of the tfdA gene, carried on plasmid pRO103, to phenol degrading recipient strains significantly increased the degradation rate of Phenoxyacetic Acid in sterile and non-sterile soil microcosms. The tfdA gene encodes a 2,4-dichloroPhenoxyacetic Acid/2-oxoglutarate dioxygenase and by complementation with the phenol degradation pathway an expanded catabolic substrate range, now including Phenoxyacetic Acid, is evolved. Presence of selective pressure had a positive effect on the emergence of transconjugants. However, even in the absence of Phenoxyacetic Acid transconjugant populations were detected and were kept at a constant level throughout the experimental period. The residuesphere (interface between decaying plant material and soil matrix) of dry leaves of barley was shown to be a hot-spot for gene transfer and presence of barley straw increased the conjugation frequencies in soil microcosms to the same extent as presence of organic nutrients. The results of this study indicate that dissemination of catabolic plasmids is a possible mechanism of genetic adaptation to degradation of xenobiotic compounds in natural environments, and that complementation of catabolic pathways possibly plays an important role in the evolution of new degradative capabilities. The application of horizontal gene transfer as a possible tool in bioremediation of contaminated sites is discussed.
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Utilization of Phenoxyacetic Acid, by strains using either the ortho or meta cleavage of catechol during phenol degradation, after conjugal transfer of tfdA , the gene encoding a 2,4-dichloroPhenoxyacetic Acid/2-oxoglutarate dioxygenase
Applied microbiology and biotechnology, 1999Co-Authors: J. Radnoti De Lipthay, Tamar Barkay, J. Vekova, Søren J. SørensenAbstract:The degradation of recalcitrant pollutants in contaminated soils and waters could be facilitated by broadening the degradative capabilities of indigenous microbes by the conjugal transfer of catabolic genes. The feasibility of establishing bacterial populations that degrade Phenoxyacetic Acid by conjugal transfer of tfdA, the gene encoding 2,4-dichloroPhenoxyacetic Acid/2-oxoglutarate dioxygenase, to phenol-degrading strains of Pseudomonas and Ralstonia was examined. The mobilizable plasmid pKJS32 served as a vector for delivery of tfdA and the regulatory gene, tfdS. Transconjugant strains that degraded phenol by an ortho cleavage of catechol grew well on Phenoxyacetic Acid while those employing a meta cleavage could only grow on Phenoxyacetic Acid in the presence of benzoic Acid or after a prolonged lag period and the appearance of mutants that had gained catechol 1,2-dioxygenase activities. Thus, an ortho cleavage of catechol was essential for degradation of Phenoxyacetic Acid, suggesting that a product of the ortho-cleavage pathway, probably cis,cis-muconic Acid, is an inducer of tfdA gene expression. Establishment of Phenoxyacetic-Acid-degrading soil populations by conjugal transfer of tfdA would depend on the presence of phenol-degrading recipients employ- ing an ortho cleavage of catechol.