A convenient and practical synthetic route for 2,4-dibromo-5-fluorobenzoic acid is described. Two intermediates, 2,4-dibromo-5-fluorobenzonitrile and 2,4-dibromo-5-fluorobenzamide, have not been reported before. This ...A convenient and practical synthetic route for 2,4-dibromo-5-fluorobenzoic acid is described. Two intermediates, 2,4-dibromo-5-fluorobenzonitrile and 2,4-dibromo-5-fluorobenzamide, have not been reported before. This route can be easily industrialized.展开更多
This study reports an investigation into the degradation of 2,4-dichlorophenoxyacetic acid in bubble contactor column by O2/H2O2 process, which is widely used as a principal advanced oxidation process. The degradation...This study reports an investigation into the degradation of 2,4-dichlorophenoxyacetic acid in bubble contactor column by O2/H2O2 process, which is widely used as a principal advanced oxidation process. The degradation of 2,4-dichlorophenoxyacetic acid was studied under different H202/O3 molar ratio and pH value. Meanwhile, TOC removal was investigated both in distilled water and tap water. The influences of ozone transfer and consumed hydrogen peroxide were also discussed. The degradation products and oxidation intermediates were identified by GC-MS and LC-MS. A possible reaction mechanism was thus proposed.展开更多
A molecularly-imprinted amino-functionalized sorbent for selective removal of 2,4-dichlorophenoxyacetic acid （2,4-D） was prepared by a surface imprinting technique in combination with a sol-gel process. The 2,4-D-im...A molecularly-imprinted amino-functionalized sorbent for selective removal of 2,4-dichlorophenoxyacetic acid （2,4-D） was prepared by a surface imprinting technique in combination with a sol-gel process. The 2,4-D-imprinted amino-functionalized silica sorbent was characterized by FT-IR, nitrogen adsorption and static adsorption experiments. The selectivity of the sorbent was investigated by a batch competitive binding experiment using an aqueous 2,4-D and 2,4-dichlorophenol （2,4-DCP） mixture or using an aqueous 2,4-D and 2,4- dichlorophenylacetic acid （DPAC） mixture. The largest selectivity coefficient for 2,4-D in the presence of 2,4-DCP was found to be over 18, the largest relative selectivity coefficient between 2,4-D and 2,4-DCP over 9. The static uptake capacity and selectivity coefficient of the 2,4-D-imprinted functionalized sorbent are higher than those of the non-imprinted sorbent. The imprinted functionalized silica gel sorbent offered a fast kinetics for the extraction/stripping of 2,4-D, 73% of binding capacity （200 mg/L 2,4-D onto 20 mg of imprinted sorbent） was obtained within 5 min and the adsorbed 2,4-D can be easily stripped by the mixture solution of ethanol and 6 mol/L HC1 （V：V =1：1）. In a test of five extraction/stripping cycles, the adsorption capacity of the sorbent was all above 93% of that of the fresh sorbent. Experimental result showed the potential of molecularly-imprinted amino-functionalized sorbent for selective removal of 2,4-D.展开更多
ABSTRAC Two new complexes [Cd（2,4＇-bpdc）（DPPZ）]2n·n H2O（1） and [Zn（2,4＇-Hbpdc）2（DPPZ）]· H2O（DPPZ = dipyrido[3,2-a：2＇,3＇-c]phenazine, 2,4＇-H2bpdc = 2,4＇-biphenyldicarboxylic acid） have been...ABSTRAC Two new complexes [Cd（2,4＇-bpdc）（DPPZ）]2n·n H2O（1） and [Zn（2,4＇-Hbpdc）2（DPPZ）]· H2O（DPPZ = dipyrido[3,2-a：2＇,3＇-c]phenazine, 2,4＇-H2bpdc = 2,4＇-biphenyldicarboxylic acid） have been hydrothermally synthesized. The structure of complex 1 was determined by single-crystal X-ray diffraction diffraction and further characterized by elemental analysis, IR spectrum, powder X-ray diffraction（XRD） and single-crystal X-ray diffraction. Complex 1 has 1D chains, which are further connected by π-π stacking interactions of neighbouring chains, generating a steady 3D supramolecular structure. Complex 2 shows the isolated mononuclear units, which are further extended to a 2D supramolecular layered structure through π-π stacking interactions and hydrogen bonds. Furthermore, complexes 1 and 2 exhibit green photoluminescent properties at room temperature.展开更多
An experimental comparison of the adsorption properties of hypercrosslinked resin AM-1 modified by phenolic hydroxyl group with Amberlite XAD-4 toward 2,4-dichlorobenzoxyacetic acid was performed. This paper focuses o...An experimental comparison of the adsorption properties of hypercrosslinked resin AM-1 modified by phenolic hydroxyl group with Amberlite XAD-4 toward 2,4-dichlorobenzoxyacetic acid was performed. This paper focuses on the static equilibrium adsorption behaviors and the adsorption thermodynamics. Two isotherm models were used to explain the results. It is seen that the Langmuir equation can give a perfect fit. The adsorption capacities from the different ranges of temperature, the adsorption enthalpy change value and the comparison of desorption conditions lead to the same conclusion that the adsorption of 2,4-dichlorobenzoxyacetic acid from water onto AM-1 is a type of physical and chemical transition.展开更多
A rapid and simple method is presented for determining β-N-oxalyl-α. β- diaminopropionic acid (β -ODAP) and its much less toxic α -isomer (α -ODAP) in Lathyrus sativus. Seed and foliage extracts of Lathyrus sat...A rapid and simple method is presented for determining β-N-oxalyl-α. β- diaminopropionic acid (β -ODAP) and its much less toxic α -isomer (α -ODAP) in Lathyrus sativus. Seed and foliage extracts of Lathyrus sativus were treated with 1-fluoro-2,4-dinitrobenzene (FDNB) and a reversed-phase high-performance liquid chromatographic method for the separation of the derivatives in the pmol range is reported.展开更多
文摘A convenient and practical synthetic route for 2,4-dibromo-5-fluorobenzoic acid is described. Two intermediates, 2,4-dibromo-5-fluorobenzonitrile and 2,4-dibromo-5-fluorobenzamide, have not been reported before. This route can be easily industrialized.
基金The National Natural Science Foundation of China (No. 50378028)
文摘This study reports an investigation into the degradation of 2,4-dichlorophenoxyacetic acid in bubble contactor column by O2/H2O2 process, which is widely used as a principal advanced oxidation process. The degradation of 2,4-dichlorophenoxyacetic acid was studied under different H202/O3 molar ratio and pH value. Meanwhile, TOC removal was investigated both in distilled water and tap water. The influences of ozone transfer and consumed hydrogen peroxide were also discussed. The degradation products and oxidation intermediates were identified by GC-MS and LC-MS. A possible reaction mechanism was thus proposed.
基金supported by the Natural Science Foundation of Zhejiang Province (No.Y505073)the Scientific Project of Zhejiang Province (No.2008C22012)
文摘A molecularly-imprinted amino-functionalized sorbent for selective removal of 2,4-dichlorophenoxyacetic acid （2,4-D） was prepared by a surface imprinting technique in combination with a sol-gel process. The 2,4-D-imprinted amino-functionalized silica sorbent was characterized by FT-IR, nitrogen adsorption and static adsorption experiments. The selectivity of the sorbent was investigated by a batch competitive binding experiment using an aqueous 2,4-D and 2,4-dichlorophenol （2,4-DCP） mixture or using an aqueous 2,4-D and 2,4- dichlorophenylacetic acid （DPAC） mixture. The largest selectivity coefficient for 2,4-D in the presence of 2,4-DCP was found to be over 18, the largest relative selectivity coefficient between 2,4-D and 2,4-DCP over 9. The static uptake capacity and selectivity coefficient of the 2,4-D-imprinted functionalized sorbent are higher than those of the non-imprinted sorbent. The imprinted functionalized silica gel sorbent offered a fast kinetics for the extraction/stripping of 2,4-D, 73% of binding capacity （200 mg/L 2,4-D onto 20 mg of imprinted sorbent） was obtained within 5 min and the adsorbed 2,4-D can be easily stripped by the mixture solution of ethanol and 6 mol/L HC1 （V：V =1：1）. In a test of five extraction/stripping cycles, the adsorption capacity of the sorbent was all above 93% of that of the fresh sorbent. Experimental result showed the potential of molecularly-imprinted amino-functionalized sorbent for selective removal of 2,4-D.
基金Supported by the Program for NNSFC(21407064,21576112)NSF of Jilin Province(20130521019JH)the Science and Technology Development Plan of Siping City(2014052,2015049)
文摘ABSTRAC Two new complexes [Cd（2,4＇-bpdc）（DPPZ）]2n·n H2O（1） and [Zn（2,4＇-Hbpdc）2（DPPZ）]· H2O（DPPZ = dipyrido[3,2-a：2＇,3＇-c]phenazine, 2,4＇-H2bpdc = 2,4＇-biphenyldicarboxylic acid） have been hydrothermally synthesized. The structure of complex 1 was determined by single-crystal X-ray diffraction diffraction and further characterized by elemental analysis, IR spectrum, powder X-ray diffraction（XRD） and single-crystal X-ray diffraction. Complex 1 has 1D chains, which are further connected by π-π stacking interactions of neighbouring chains, generating a steady 3D supramolecular structure. Complex 2 shows the isolated mononuclear units, which are further extended to a 2D supramolecular layered structure through π-π stacking interactions and hydrogen bonds. Furthermore, complexes 1 and 2 exhibit green photoluminescent properties at room temperature.
文摘An experimental comparison of the adsorption properties of hypercrosslinked resin AM-1 modified by phenolic hydroxyl group with Amberlite XAD-4 toward 2,4-dichlorobenzoxyacetic acid was performed. This paper focuses on the static equilibrium adsorption behaviors and the adsorption thermodynamics. Two isotherm models were used to explain the results. It is seen that the Langmuir equation can give a perfect fit. The adsorption capacities from the different ranges of temperature, the adsorption enthalpy change value and the comparison of desorption conditions lead to the same conclusion that the adsorption of 2,4-dichlorobenzoxyacetic acid from water onto AM-1 is a type of physical and chemical transition.
基金Tshe prOject!(39770469) supported by the National Natural Science Foundation of China.
文摘A rapid and simple method is presented for determining β-N-oxalyl-α. β- diaminopropionic acid (β -ODAP) and its much less toxic α -isomer (α -ODAP) in Lathyrus sativus. Seed and foliage extracts of Lathyrus sativus were treated with 1-fluoro-2,4-dinitrobenzene (FDNB) and a reversed-phase high-performance liquid chromatographic method for the separation of the derivatives in the pmol range is reported.
