In this study, the ethanol extract of pomegranate seed was prepared and its antioxidant activities were investigated. It was found the total phenolic content in the extract was as high as 41.791 mg GAE/g. And the extr...In this study, the ethanol extract of pomegranate seed was prepared and its antioxidant activities were investigated. It was found the total phenolic content in the extract was as high as 41.791 mg GAE/g. And the extract showed high antioxidant activity measured as scavenging of DPPH radicals, hydroxyl radicals. It also exhibited strong antioxidant activity in reducing power and Rancimat test. These results demonstrated Pomegranate seeds could serve as a new source of natural antioxidant.展开更多
The degradation of 4-chloro-3-methylphenol(PCMC)using zeolite-encapsulated iron(III),nickel(II),and copper(II)complexes of N,N’-disalicylidene-1,2-phenylenediamine as catalysts,in a heterogeneous Fenton-like ...The degradation of 4-chloro-3-methylphenol(PCMC)using zeolite-encapsulated iron(III),nickel(II),and copper(II)complexes of N,N’-disalicylidene-1,2-phenylenediamine as catalysts,in a heterogeneous Fenton-like advanced oxidation process,was studied.The physicochemical properties of the catalysts were determined using powder X-ray diffraction,thermogravimetric analysis,Brunauer–Emmett–Teller surface area analysis,Fourier-transform infrared spectroscopy,elemental analysis,and scanning electron microscopy.The effects of four factors,namely initial H2O2 concentration,catalyst dosage,temperature,and pH,on the degradation of a model organic pollutant were determined.The results show that at low acidic pH,almost complete removal of PCMC was achieved with the iron(III),nickel(II),and copper(II)catalysts after 120 min under the optimum reaction conditions:catalyst dosage 0.1 g,H2O2 concentration 75 mmol/L,initial PCMC concentration 0.35mmol/L,and 50 °C.The reusability of the prepared catalysts in PCMC degradation was also studied and a possible catalyst deactivation mechanism is proposed.The possible intermediate products,degradation pathway,and kinetics of PCMC oxidation were also studied.展开更多
The reaction mechanism and kinetics for the addition of hydroxyl radical (OH) to phenol have been investigated using the hybrid density functional (B3LYP) method with the 6-31++G(2dp, 2dr) basis set and the co...The reaction mechanism and kinetics for the addition of hydroxyl radical (OH) to phenol have been investigated using the hybrid density functional (B3LYP) method with the 6-31++G(2dp, 2dr) basis set and the complete basis set (CBS) method using APNO basis sets, respectively. The equilibrium geometries, energies, and thermodynamics properties of all the stationary points along the addition reaction pathway are calculated. The rate constants and the branching ratios of each channel are evaluated using classical transition state theory (TST) in the temperature range of 210 to 360 K, to simulate temperatures in all parts of the troposphere. The ortho addition pathway is dominant and accounts for 99.8%-96.7% of the overall adduct products from 210 to 360 K. The calculated rate constants are in good agreement with existing experimental values. The addition reaction is irreversible.展开更多
基金Supported by Foundation for Science and Technology Research Program of Henanprovince(132102110007102102210194)+1 种基金Natural Science Foundation of EducationDepartment in Henan province(2011A550006)Program for Innovative Research Team(in Science and Technology)in University of Henan Province(13IRTSTHN006)
文摘In this study, the ethanol extract of pomegranate seed was prepared and its antioxidant activities were investigated. It was found the total phenolic content in the extract was as high as 41.791 mg GAE/g. And the extract showed high antioxidant activity measured as scavenging of DPPH radicals, hydroxyl radicals. It also exhibited strong antioxidant activity in reducing power and Rancimat test. These results demonstrated Pomegranate seeds could serve as a new source of natural antioxidant.
基金Leather Industry Development Institute(LIDI),Government of Ethiopia,Addis Ababa,for full financial support for his PhD studies under Twinning Program between Leather Industry Development Institute(LIDI),Addis Ababa University(AAU)and CSIR-Central Leather Research Institute(CLRI)
文摘The degradation of 4-chloro-3-methylphenol(PCMC)using zeolite-encapsulated iron(III),nickel(II),and copper(II)complexes of N,N’-disalicylidene-1,2-phenylenediamine as catalysts,in a heterogeneous Fenton-like advanced oxidation process,was studied.The physicochemical properties of the catalysts were determined using powder X-ray diffraction,thermogravimetric analysis,Brunauer–Emmett–Teller surface area analysis,Fourier-transform infrared spectroscopy,elemental analysis,and scanning electron microscopy.The effects of four factors,namely initial H2O2 concentration,catalyst dosage,temperature,and pH,on the degradation of a model organic pollutant were determined.The results show that at low acidic pH,almost complete removal of PCMC was achieved with the iron(III),nickel(II),and copper(II)catalysts after 120 min under the optimum reaction conditions:catalyst dosage 0.1 g,H2O2 concentration 75 mmol/L,initial PCMC concentration 0.35mmol/L,and 50 °C.The reusability of the prepared catalysts in PCMC degradation was also studied and a possible catalyst deactivation mechanism is proposed.The possible intermediate products,degradation pathway,and kinetics of PCMC oxidation were also studied.
基金supported by the National Natural Science Foundation of China (20977064)
文摘The reaction mechanism and kinetics for the addition of hydroxyl radical (OH) to phenol have been investigated using the hybrid density functional (B3LYP) method with the 6-31++G(2dp, 2dr) basis set and the complete basis set (CBS) method using APNO basis sets, respectively. The equilibrium geometries, energies, and thermodynamics properties of all the stationary points along the addition reaction pathway are calculated. The rate constants and the branching ratios of each channel are evaluated using classical transition state theory (TST) in the temperature range of 210 to 360 K, to simulate temperatures in all parts of the troposphere. The ortho addition pathway is dominant and accounts for 99.8%-96.7% of the overall adduct products from 210 to 360 K. The calculated rate constants are in good agreement with existing experimental values. The addition reaction is irreversible.