Purification of surface water is widely practiced with conventional water treatment processes like coagulation-flocculation, sedimentation, filtration,and disinfection. Some reports have specified that conventional wa...Purification of surface water is widely practiced with conventional water treatment processes like coagulation-flocculation, sedimentation, filtration,and disinfection. Some reports have specified that conventional wastewater purification processes do not effectively remove many chemical contaminants,展开更多
The solvent extractable organic compounds (SEOC), including n-alkanes, polycylic aromatic hydrocarbons, fatty acids, and dicarboxylic acids in PM2.5 during the 2007 Chinese Spring Festival in Beijing, were measured ...The solvent extractable organic compounds (SEOC), including n-alkanes, polycylic aromatic hydrocarbons, fatty acids, and dicarboxylic acids in PM2.5 during the 2007 Chinese Spring Festival in Beijing, were measured via gas chromatography-mass spectrometry for determining the characteristics and sources of these organic pollutants. The concentrations of total n-alkanes, PAHs, and organic acids before Chinese Spring Festival Eve (1025.5, 95.9, and 543.3 ng/m3, respectively) were higher than those after (536.6, 58.9, and 331.8 ng/m3, respectively), n-Aalkanes and PAHs had much higher concentration in nighttime than those in daytime because of high relative humidity and low wind speed during the night. Combustion of coal and exhaust emission were major sources of n- alkanes. It could be concluded by the characteristic ratios that the primary source of PAHs in fine particles was the combustion of coal, but the combustion of gasoline was in the next place. The ratios of C18:0/C16 indicated the contribution of vehicular emissions to the fatty acids. Dicarboxylic and aromatic acids were abundant in daytime than in nighttime because these acids were secondary organic acid and the photochemical degradation of aromatic hydrocarbons was the main source.展开更多
Water erosion is the major reason for the loss of soil organic carbon in the Northeast China, which leads to the soil quality deterioration and adjacent water pollution. In this study, the effect of extraction tempera...Water erosion is the major reason for the loss of soil organic carbon in the Northeast China, which leads to the soil quality deterioration and adjacent water pollution. In this study, the effect of extraction temperature, pH value, and salt on the water extractable organic matter (WEOM) was determined by means of the UV absorbance, fluorescence excitation-emission matrix, and derived fluorescence indexes. In general, the carbon content and aromaticity of WEOM increased with the increasing of extraction temperature, with the exception that there was no significant difference in the amount at 0 and 20℃. More fluorophores, especially microbially-derived organic matter were extracted at high temperature. The pH values of extractant, including 5, 7, and 10, showed no effect on the carbon amount of WEOM, whereas the aromaticity and microbially-derived component gradually increased with the increasing of pH values. The fluorescence intensity of humic acid-like fluorophore was stronger in neutral and alkali condition than that in acidic condition. The addition of 10 mmol L-1 CaCl2 significantly decreased the carbon amount of recovered WEOM. Moreover, it significantly decreased the aromaticity of WEOM and the quantity of fulvic acid-like and humic acid-like fluorophores, whereas increased the percentage of tyrosine-like and tryptophan-like fluorophores in the total fluorophores and the amount of microbially-derived organic matter. Generally, 10 mmol L-1 KCl showed the same influence trend, but with low influence degree.展开更多
Water soluble organic carbon (WSOC) is considered the most mobile and reactive soil carbon source and its characterization is an important issue for soil ecology study. A biodegradability test was set up to study WS...Water soluble organic carbon (WSOC) is considered the most mobile and reactive soil carbon source and its characterization is an important issue for soil ecology study. A biodegradability test was set up to study WSOC extracted from 7 soils differently managed. WSOC was extracted from soil with water (soil/water ratio of 1:2, W/V) for 30 min, and then tested for biodegradability by a liquid state respirometric test. Result obtained confirmed the finding that WSOC biodegradability depended on the both land use and management practice. These results suggested the biodegradability test as suitable method to characterize WSOC, and provided useful information to soil fertility.展开更多
AIM: To evaluate the antimicrobial potential of Terminalia chebula ( T. chebula) extracts against pathogens causing otitis externa and compare it with ear drops.METHODS: Four different extracts, methanol, ethanol...AIM: To evaluate the antimicrobial potential of Terminalia chebula ( T. chebula) extracts against pathogens causing otitis externa and compare it with ear drops.METHODS: Four different extracts, methanol, ethanol, acetone and aqueous (hot and cold) extracts, from the T. chebula were tested for their antimicrobial activity through the agar well diffusion method and minimum inhibitory concentration (MIC)/minimum bactericidal concentration (MBC) values were determined through the macrodilution broth method against six different microorganism, five bacterial (one gram positive and four gram negative) and one yeast.RESULTS: Organic and aqueous fruit extracts displayed activity against all fve tested bacterial ear pathogens with a maximum zone of inhibition of 31.6 mm against Staphylococcus aureus , followed by Acinetobacter sp. (24.6 mm), Pseudomonas aeruginosa (23.6 mm), Proteus mirabilis (21 mm) and Escherichia coli (19.3mm). Of the four solvents evaluated, acetonic fruit extract of T. chebula was found to be best. The MIC values ranged between 0.78 mg/mL and 50 mg/mL for the different bacterial ear pathogens and MBC values ranged between 1.56 mg/mL and 50 mg/mL. The acetonic fruit extract showed larger inhibition zones compared to the herbal ear drops, Kan pip with lowest MIC of 0.78 mg/mL and MBC of 1.56 mg/mL.CONCLUSION: Acetonic extract of T. chebula fruit may be used to treat otitis externa. However, more detailed studies, such as in vivo testing and pharmacokinetics properties, are needed to determine its therapeutic potential.展开更多
The dust derived from an aluminum electrolytic plant was collected on a filter, then extracted with benzene. The benzene soluble material was separated into five fractions, namely organic acid, organic alkali, aliphat...The dust derived from an aluminum electrolytic plant was collected on a filter, then extracted with benzene. The benzene soluble material was separated into five fractions, namely organic acid, organic alkali, aliphatic hydrocarbon, polycyclic aromatic hydrocarbon and polar compounds. The mutagenic activities of these fractions were examined with two strains of Salmonella typhimurium mutants. It was demonstrated that the dust organic extract showed a very strong mutagenic activity. Among the five fractions tested, three fractions, namely organic acid, polycyclic aromatic hydrocarbon and polar compounds, played an important role in the mutagenic activity of the dust organic extract. The other two fractions, organic alkali and aliphatic hydrocarbon had no mutagenic activities. Therefore, dust abatement is an important measure in aluminum plants for controlling carcinogens, mutagens and protecting the environment and human health.展开更多
The allelopathic potential of aqueous and organic solvent extacts from Corrigiola telephiifolia Pour which is an aromatic and medicinal plant in mediterranean regions, was investigated under laboratory conditions on t...The allelopathic potential of aqueous and organic solvent extacts from Corrigiola telephiifolia Pour which is an aromatic and medicinal plant in mediterranean regions, was investigated under laboratory conditions on two plant species: Raphanus sativus and Triticum aestivum. The aqueous extract of Corrigiola telephiifolia roots had an important inhibitory effect on the seed germination of the two tested plant species. The dichloromethane and the methanol extracts significantly reduced the growth of radish roots up to 84.44% and 68.85% respectively. The butanol, the dichloromethane and the ethyl acetate extracts had a high inhibitory effect on seed germination and roots growth of wheat. The presence of saponins in butanol extracts and tanins in dichlorometane and ethyl acetate extracts may be responsible of these allelopathic activities. These results suggest that Corrigiola telephiifolia Pour have allelopathic effects and contains potent allelochemicals which should be used for weeds management.展开更多
All-China Federation of Trade Unions On this occasion of the 30th anniversary of the Chinese Association for International Understanding (CAFIU), the All-China Federation of Trade Unions would like to send its warmest...All-China Federation of Trade Unions On this occasion of the 30th anniversary of the Chinese Association for International Understanding (CAFIU), the All-China Federation of Trade Unions would like to send its warmest congratulations. Since its founding, CAFIU展开更多
Phytochemical studies and antioxidant activities were carried out on n-hexane, ethyl acetate, ethanol and methanol extracts of the leaves of Lippia rugosa A. Chev (Verbenaceae), a medicinal plant used traditionally in...Phytochemical studies and antioxidant activities were carried out on n-hexane, ethyl acetate, ethanol and methanol extracts of the leaves of Lippia rugosa A. Chev (Verbenaceae), a medicinal plant used traditionally in the Cameroonian savannah’s region to protect foodstuffs and to cure degenerative diseases. Results indicated that theses extracts contain terpenoids, phenolic and flavonoid compounds. Except the n-hexane extract, all of the obtained extracts exhibit antioxidant activities with the ethanol extract being the most effective with an inhibition percentage of 85.668% ± 1.233% and an inhibition concentration (IC<sub>50</sub>) of 58 μg/ml (R<sup>2</sup> = 0.987, P < 0.01) at a concentration of 100 mg/ml. Chromatographic separation on silica gel of the ethanol extract led to the isolation of a pure organic compound which was characterized as 7-hydroxy-5,6,4'-trimethox- yflavone by extensive 1D and 2D NMR spectroscopy, a flavonoid exhibiting antioxidative activity with an inhibitory percentage of 25.506% ± 0.205% and inhibition concentration (IC<sub>50</sub>) of 221 μg/ml (R<sup>2</sup> = 0.966, P < 0.01). This is the first time that 7-hydroxy-5,6,4'-trimethoxyflavone is being isolated from L. rugosa and its antioxidant activity evaluated.展开更多
Chicken manures added with Cu and Zn were used for composting experiment to study the dynamics of different soluble humus complexed copper (H2O-Cu,NaOH-Cu and NaOH-Na4P2O7-Cu).The effect of zinc in compost on humus ...Chicken manures added with Cu and Zn were used for composting experiment to study the dynamics of different soluble humus complexed copper (H2O-Cu,NaOH-Cu and NaOH-Na4P2O7-Cu).The effect of zinc in compost on humus complexed copper and the relationship between humus complexed copper were also revealed.The results showed that H2O-Cu increased before the 45 d of composting and decreased thereafter.In the treatments of 1:1,2:1 and 3:1 with the added copper content increasing,H2O-Cu increased with decomposition process.Added high level zinc in manure could decrease the relative H2O-Cu content at the last stage of composting.NaOH-Cu decreased greatly with the compost proceeding.With the added copper content increasing in manure,the percentage of NaOH-Cu to total copper decreased.Added zinc had no significant impact on NaOH-Cu concentration.NaOH-Na4P2O7-Cu increased with composting.With the added copper content increasing in compost manure,the percentage of NaOH-Na4P2O7-Cu to total copper increased,and showed an increase trend with composting proceeding.Added zinc in manure increased NaOH-Na4P2O7-Cu.In composts,55-80% of extracted copper was present in NaOH fraction,10-30% in NaOH-Na4P2O7-Cu fraction,and 0-10% in H2O fraction.Whatever the added copper or zinc contents increased in manures,the distribution percent of NaOH- Na4P2O7-Cu (pressed as percent of extracted Cu) increased and that of H2O-Cu and NaOH-Cu decreased.Three extracted Cu (H2O,NaOH and Na4P2O7) were strongly correlated to each other,H2O-Cu and NaOH-Na4P2O7-Cu were significantly correlated to H2O-extracted organic C and NaOH-Na4P2O7-extracted organic C,respectively.展开更多
Comprehensive nitrogen biogeochemical cycle has been reconstructed for representative lacustrine organic-rich sedimentary rock in China,namely the Triassic Yanchang Formation(YF,199–230 Ma)in Ordos and the Cretaceous...Comprehensive nitrogen biogeochemical cycle has been reconstructed for representative lacustrine organic-rich sedimentary rock in China,namely the Triassic Yanchang Formation(YF,199–230 Ma)in Ordos and the Cretaceous Qingshankou Formation(QF,86–92 Ma)in Songliao basins,by evaluating the organic and inorganic nitrogen isotopic compositions rather than only organic or bulk nitrogen isotopic compositions.The results indicate that the nitrogen isotope values of bulk rock(δ^(15)N_(bulk))in the non-metamorphic stage are significantly different from that of kerogen,which challenge the conceptual framework of sedimentary nitrogen isotope interpretation.Theδ^(15)N_(bulk)from the YF and QF were lower than their respective the nitrogen isotope values of kerogen(δ^(15)N_(ker)),with offsets up to5.1‰,which have the inverse relationship for the metamorphosed rock.Thermal evolution did not significantly modify the d15N of bulk rock and kerogen.The d15N of sediments from the YF(δ^(15)N_(bulk),1.6‰–5.6‰)were lower than that of rock from the QF(δ^(15)N_(bulk),10.2‰–15.3‰).The nitrogen isotope values of silicate incorporated nitrogen(δ^(15)N_(sil))were slightly lower than those of the d15Nker in the YF and obviously lower for the QF.The fact that different nitrogen cycles occur in the YF and QF due to the different depositional redox conditions leads to different isotopic results.The YF water environment dominated by oxic conditions is not conducive to the occurrence of denitrification and anammox,and no abundant N2 loss leads to the relatively lightδ^(15)N_(bulk).In the stratified water for the QF,redox transition zone promotes denitrification and anammox,resulting in the heavyδ^(15)N_(bulk)of rock and promotes the DNRA,resulting in heavyδ^(15)N_(ker)and lowδ^(15)N_(sil).展开更多
Investigating the effects of residue chemical composition on soil labile organic carbon (LOC) will improve our understanding of soil carbon sequestration. The effects of maize residue chemical composition and soil w...Investigating the effects of residue chemical composition on soil labile organic carbon (LOC) will improve our understanding of soil carbon sequestration. The effects of maize residue chemical composition and soil water content on soil LOC fractions and microbial properties were investigated in a laboratory incubation experiment. Maize shoot and root residues were incorporated into soil at 40% and 70% field capacity. The soils were incubated at 20 ℃ for 150 d and destructive sampling was conducted after 15, 75, and 150 d. Respiration, dissolved organic carbon (DOC), hot-water extractable organic carbon (HEOC), and microbial biomass carbon (MBC) were recorded, along with cellulase and β-glucosidase activities and community-level physiological profiles. The results showed that the cumulative respiration was lower in root-amended soils than in shoot-amended soils, indicating that root amendment may be beneficial to C retention in soil. No significant differences in the contents of DOG, HEOC and MBC, enzyme activities, and microbial functional diversity were observed between shoot- and root-amended soils. The high soil water content treatment significantly increased the cumulative respiration, DOC and HEOC contents, and enzyme activities compared to the low soil water content treatment. However, the soil water content treatments had little influence on the MBC content and microbial functional diversity. There were significantly positive correlations between LOC fractions and soil microbial properties. These results indicated that the chemical composition of maize residues had little influence on the DOC, HEOC, and MBC contents, enzyme activities, and microbial functional diversity, while soil water content could significantly influence DOC and HEOC contents and enzyme activities.展开更多
To examine the activation of organic acids on the leaching process of ion-adsorption type rare earth ore(IRE-ore), the leaching behavior of rare earth(RE) and zeta potential of IRE-ore were investigated in the abs...To examine the activation of organic acids on the leaching process of ion-adsorption type rare earth ore(IRE-ore), the leaching behavior of rare earth(RE) and zeta potential of IRE-ore were investigated in the absence and presence of carboxylic acids. The results show that all the tested organic acids(acetic acid,malonic acid, citric acid, tartaric acid, succinic acid, and malic acid) can promote RE extraction. At relatively high concentrations of organic acids, the activation efficiency of organic acids on RE extraction is generally consistent with their complexation ability; whereas at their low concentrations, the change of zeta potential on the IRE-ore surface with organic acid concentration and p H has a close association with RE extraction, which indicates that organic acids can impact the surface electrical property of IREore via their adsorption/desorption, and thereby increase/decrease the affinity of RE ions to IRE-ore.Therefore the influence of organic acids on the IRE-ore surface electrical property also plays an important role in RE extraction in addition to their complexation with RE ions.展开更多
In most organics extraction processes, the commonly used solvents employ solely physical interactions. Therefore, for the recovery and purification of products from complex mixtures, the selectivity and/or capacity of...In most organics extraction processes, the commonly used solvents employ solely physical interactions. Therefore, for the recovery and purification of products from complex mixtures, the selectivity and/or capacity of classical solvents towards the desired solutes is usually insufficient, enforcing the need for complex and thus expensive separation schemes. Significant simplification and cost-reduction can be achieved when affinity solvents would be available that are able to recognize the solutes of interest by their molecular structure. The main development challenges to establish such affinity solvents are: Selection and incorporation of molecular recognition and complexation capabilities; Evaluation of extraction capabilities; Efficient re- covery and recycling of the affinity solvents; Implementation in industrial extraction equipment. This paper presents how these development challenges are addressed at the University of Twente, going all the way from affinity solvent design and synthesis, via high throughput screening and characterization up to pilot plant evaluation. Essential in the successful development of affinity solvents are structural cooperations with molecular chemists and custom synthesis companies for their design and synthesis. The various aspects are illustrated by several examples where newly developed environmentally benign affinity solvents appeared able to create major breakthroughs. The applications addressed involve oxygenates, sugars, and pharmaceutical ingredients, such as optical isomers and biomolecules.展开更多
Solution ^(31)P nuclear magnetic resonance spectroscopy( ^(31)P-NMR) is a useful method to analyze organic phosphorus(Po), but a general procedure for the analysis method is lacking.The authors used solution ^...Solution ^(31)P nuclear magnetic resonance spectroscopy( ^(31)P-NMR) is a useful method to analyze organic phosphorus(Po), but a general procedure for the analysis method is lacking.The authors used solution ^(31)P-NMR, which was found to be an effective method for analysis of Po in Haihe River sediment, to analyze the Po in the surface sediment in Eastern China at the regional scale, and found that the Na OH-ethylenediaminetetraacetic acid(EDTA)extraction rate was affected by environmental factors. At the regional scale, the extraction rate showed a positive relationship with loss on ignition, when the extraction rate was lower than 60%. The extraction rate had no relationship with the loss on ignition when the extraction rate was higher than 60%. The extraction rate showed a negative relationship with p H, which means that the extraction rate was higher in acidic sediment and lower in alkaline sediment. The ratio of TC/TN(the ratio of total carbon to total nitrogen) was considered to represent the origin of organic matter in the sediment. The extraction rate was high when the TC/TN ratio was lower than 20, meanwhile the extraction rate decreased as the TC/TN ratio increased. The results show that the origin of organic matter in sediment significantly affects the Na OH-EDTA extraction rate. This study will give theoretical support for building an effective and general solution ^(31)P-NMR analysis method.展开更多
The toxicity of soil irrigated with treated domestic wastewater (site A) and untreated gray wastewater (site B) were investigated. Soil extracts were prepared using distilled water, acid solvent (0.1 mol·L-1...The toxicity of soil irrigated with treated domestic wastewater (site A) and untreated gray wastewater (site B) were investigated. Soil extracts were prepared using distilled water, acid solvent (0.1 mol·L-1 HCl), and organic solvent (acetone:petroleum ether:cyclohexane= 1:1:1) to understand the type of pollutants responsible for the ecotoxicity associated with wastewater irrigation. The soil toxicity was assessed using a luminescence inhibition assay with Vibrio fischeri for acute toxicity, a micronucleus assay with Vicia faba root tips and a single cell gel electrophoresis assay of mice lymphocytes for genotoxicity. The physicochemical properties and the heavy metal (HM) contents of the irrigated soil were also analyzed. The results indicated that the wastewater irrigation at site A had no effects on the soil properties. With the exception of Pb, Zn, Fe, and Mn, the accumulation of HMs (Cu, Ni, and Cr) occurred. However, the irrigation at site A did not result in obvious acute toxicity or genotoxicity in the soil. The soil properties changed greatly, and HMs (Cu, Ni, and Cr) accumulated in site B. There were significant increases in the acute toxic and genotoxic effects in the soils from site B. The ecotoxicity in site B came primarily from organic-extractable pollutants.展开更多
To better understand the role of organic matter(OM)prepared from chicken manure and agriculture residues compost on the growth of plants(Lepidium sativum L.)and antagonistic fungi(Trichoderma harzianum),we analyzed th...To better understand the role of organic matter(OM)prepared from chicken manure and agriculture residues compost on the growth of plants(Lepidium sativum L.)and antagonistic fungi(Trichoderma harzianum),we analyzed the structure and composition of extracted OM using fluorescence excitation-emission matrix(EEM)spectroscopy and solid-state13C cross-polarization magic-anglespinning nuclear magnetic resonance(13C CPMAS NMR)spectroscopy.The results showed that the EEM contours of water-extracted OM(WEOM)and alkali-extracted OM(AEOM)were similar.Furthermore,solid-state13C CPMAS NMR spectroscopy demonstrated that water extraction could not proportionally pull out aromatic moieties(112–145 ppm)from compost,but the alkali method in proportion extracted both carbohydrates(65–85 ppm)and aromatic moieties.The results suggest that AEOM may better reflect the bulk OM composition of compost,and one should be cautious when applying WEOM as an alternative indicator of total compost OM.Further investigations demonstrated that,compared to carbohydrates,aromatic moieties played a predominant role in growth suppression of Lepidium sativum L.seeds and Trichoderma harzianum.展开更多
Bioavailability is a critical factor for assessing the environmental risk of organic pollutants in soil. In this study, extractions with 3 different solvents, including 2 aqueous solutions, calcium chloride(CaCl_2) an...Bioavailability is a critical factor for assessing the environmental risk of organic pollutants in soil. In this study, extractions with 3 different solvents, including 2 aqueous solutions, calcium chloride(CaCl_2) and a phosphate buffer solution(PBS), and a mixture of aqueous solution and organic solvent, a PBS-methanol(8:2,volume/volume) mixture(PBS-M), were performed to assess the bioavailability of chlorimuron-ethyl in soil in comparison to a battery of toxicity tests in wheat seedlings. The results indicated that the peroxidase(POD) activity in wheat leaves after 7 d of exposure was one of the sensitive biomarkers of chlorimuron-ethyl in soil.The extractability of chlorimuron-ethyl by all the 3 solvents decreased with exposure time, and the rate of decrease of the PBS-M extraction between 1 and 7 d of exposure was substantially higher than those of the aqueous solution extractions. Chlorimuron-ethyl gradually changed from a water-soluble form into a soil organic matter(SOM)-bound form in the soil. The PBS extraction correlated best with the POD activity in the leaves after 7 d of exposure.展开更多
In this study,allelochemicals were extracted from pulping effluents rather than from the raw ma-terial of plants.Herein,five organic solvents(ethyl acetate(EAC),methyl tert-butyl ether(MTBE),dichloromethane(DCM),carbo...In this study,allelochemicals were extracted from pulping effluents rather than from the raw ma-terial of plants.Herein,five organic solvents(ethyl acetate(EAC),methyl tert-butyl ether(MTBE),dichloromethane(DCM),carbon tetrachloride(CTC),and petroleum(PE))were applied to sep-arately extracting the allelochemicals from alkaline peroxide mechanical pulp(APMP)effluents.The results from the algal density,inhibition ratio,and optical density of 446 nm(OD 446nm)concluded that the extractives from the APMP effluents can act as effective allelochemicals and showed noticeable allelopathic inhibition effects on Microcystis aeruginosa growth.The results in-dicated that organic solvent extraction could be a practical approach to isolate the allelochemicals from the APMP effluents,which would broaden the potential application of the APMP effluents in the production of antimicrobial agents and other value-added materials.展开更多
基金supported by grants from Science and Technology Planning Project of Shenzhen [No.200703079]
文摘Purification of surface water is widely practiced with conventional water treatment processes like coagulation-flocculation, sedimentation, filtration,and disinfection. Some reports have specified that conventional wastewater purification processes do not effectively remove many chemical contaminants,
基金supported by the National Basic Re-search Program (973) of China (No. 2007CB407303)the National Natural Science Foundation of China (No.40525016)the Hi-Tech Research and Development Program (863) of China (No. 2006AA06A301).
文摘The solvent extractable organic compounds (SEOC), including n-alkanes, polycylic aromatic hydrocarbons, fatty acids, and dicarboxylic acids in PM2.5 during the 2007 Chinese Spring Festival in Beijing, were measured via gas chromatography-mass spectrometry for determining the characteristics and sources of these organic pollutants. The concentrations of total n-alkanes, PAHs, and organic acids before Chinese Spring Festival Eve (1025.5, 95.9, and 543.3 ng/m3, respectively) were higher than those after (536.6, 58.9, and 331.8 ng/m3, respectively), n-Aalkanes and PAHs had much higher concentration in nighttime than those in daytime because of high relative humidity and low wind speed during the night. Combustion of coal and exhaust emission were major sources of n- alkanes. It could be concluded by the characteristic ratios that the primary source of PAHs in fine particles was the combustion of coal, but the combustion of gasoline was in the next place. The ratios of C18:0/C16 indicated the contribution of vehicular emissions to the fatty acids. Dicarboxylic and aromatic acids were abundant in daytime than in nighttime because these acids were secondary organic acid and the photochemical degradation of aromatic hydrocarbons was the main source.
基金supported by the National Natural Science Foundation of China (51109089 and 31071862)
文摘Water erosion is the major reason for the loss of soil organic carbon in the Northeast China, which leads to the soil quality deterioration and adjacent water pollution. In this study, the effect of extraction temperature, pH value, and salt on the water extractable organic matter (WEOM) was determined by means of the UV absorbance, fluorescence excitation-emission matrix, and derived fluorescence indexes. In general, the carbon content and aromaticity of WEOM increased with the increasing of extraction temperature, with the exception that there was no significant difference in the amount at 0 and 20℃. More fluorophores, especially microbially-derived organic matter were extracted at high temperature. The pH values of extractant, including 5, 7, and 10, showed no effect on the carbon amount of WEOM, whereas the aromaticity and microbially-derived component gradually increased with the increasing of pH values. The fluorescence intensity of humic acid-like fluorophore was stronger in neutral and alkali condition than that in acidic condition. The addition of 10 mmol L-1 CaCl2 significantly decreased the carbon amount of recovered WEOM. Moreover, it significantly decreased the aromaticity of WEOM and the quantity of fulvic acid-like and humic acid-like fluorophores, whereas increased the percentage of tyrosine-like and tryptophan-like fluorophores in the total fluorophores and the amount of microbially-derived organic matter. Generally, 10 mmol L-1 KCl showed the same influence trend, but with low influence degree.
文摘Water soluble organic carbon (WSOC) is considered the most mobile and reactive soil carbon source and its characterization is an important issue for soil ecology study. A biodegradability test was set up to study WSOC extracted from 7 soils differently managed. WSOC was extracted from soil with water (soil/water ratio of 1:2, W/V) for 30 min, and then tested for biodegradability by a liquid state respirometric test. Result obtained confirmed the finding that WSOC biodegradability depended on the both land use and management practice. These results suggested the biodegradability test as suitable method to characterize WSOC, and provided useful information to soil fertility.
基金Supported by Kurukshetra University,Kurukshetra,Haryana
文摘AIM: To evaluate the antimicrobial potential of Terminalia chebula ( T. chebula) extracts against pathogens causing otitis externa and compare it with ear drops.METHODS: Four different extracts, methanol, ethanol, acetone and aqueous (hot and cold) extracts, from the T. chebula were tested for their antimicrobial activity through the agar well diffusion method and minimum inhibitory concentration (MIC)/minimum bactericidal concentration (MBC) values were determined through the macrodilution broth method against six different microorganism, five bacterial (one gram positive and four gram negative) and one yeast.RESULTS: Organic and aqueous fruit extracts displayed activity against all fve tested bacterial ear pathogens with a maximum zone of inhibition of 31.6 mm against Staphylococcus aureus , followed by Acinetobacter sp. (24.6 mm), Pseudomonas aeruginosa (23.6 mm), Proteus mirabilis (21 mm) and Escherichia coli (19.3mm). Of the four solvents evaluated, acetonic fruit extract of T. chebula was found to be best. The MIC values ranged between 0.78 mg/mL and 50 mg/mL for the different bacterial ear pathogens and MBC values ranged between 1.56 mg/mL and 50 mg/mL. The acetonic fruit extract showed larger inhibition zones compared to the herbal ear drops, Kan pip with lowest MIC of 0.78 mg/mL and MBC of 1.56 mg/mL.CONCLUSION: Acetonic extract of T. chebula fruit may be used to treat otitis externa. However, more detailed studies, such as in vivo testing and pharmacokinetics properties, are needed to determine its therapeutic potential.
文摘The dust derived from an aluminum electrolytic plant was collected on a filter, then extracted with benzene. The benzene soluble material was separated into five fractions, namely organic acid, organic alkali, aliphatic hydrocarbon, polycyclic aromatic hydrocarbon and polar compounds. The mutagenic activities of these fractions were examined with two strains of Salmonella typhimurium mutants. It was demonstrated that the dust organic extract showed a very strong mutagenic activity. Among the five fractions tested, three fractions, namely organic acid, polycyclic aromatic hydrocarbon and polar compounds, played an important role in the mutagenic activity of the dust organic extract. The other two fractions, organic alkali and aliphatic hydrocarbon had no mutagenic activities. Therefore, dust abatement is an important measure in aluminum plants for controlling carcinogens, mutagens and protecting the environment and human health.
文摘The allelopathic potential of aqueous and organic solvent extacts from Corrigiola telephiifolia Pour which is an aromatic and medicinal plant in mediterranean regions, was investigated under laboratory conditions on two plant species: Raphanus sativus and Triticum aestivum. The aqueous extract of Corrigiola telephiifolia roots had an important inhibitory effect on the seed germination of the two tested plant species. The dichloromethane and the methanol extracts significantly reduced the growth of radish roots up to 84.44% and 68.85% respectively. The butanol, the dichloromethane and the ethyl acetate extracts had a high inhibitory effect on seed germination and roots growth of wheat. The presence of saponins in butanol extracts and tanins in dichlorometane and ethyl acetate extracts may be responsible of these allelopathic activities. These results suggest that Corrigiola telephiifolia Pour have allelopathic effects and contains potent allelochemicals which should be used for weeds management.
文摘All-China Federation of Trade Unions On this occasion of the 30th anniversary of the Chinese Association for International Understanding (CAFIU), the All-China Federation of Trade Unions would like to send its warmest congratulations. Since its founding, CAFIU
文摘Phytochemical studies and antioxidant activities were carried out on n-hexane, ethyl acetate, ethanol and methanol extracts of the leaves of Lippia rugosa A. Chev (Verbenaceae), a medicinal plant used traditionally in the Cameroonian savannah’s region to protect foodstuffs and to cure degenerative diseases. Results indicated that theses extracts contain terpenoids, phenolic and flavonoid compounds. Except the n-hexane extract, all of the obtained extracts exhibit antioxidant activities with the ethanol extract being the most effective with an inhibition percentage of 85.668% ± 1.233% and an inhibition concentration (IC<sub>50</sub>) of 58 μg/ml (R<sup>2</sup> = 0.987, P < 0.01) at a concentration of 100 mg/ml. Chromatographic separation on silica gel of the ethanol extract led to the isolation of a pure organic compound which was characterized as 7-hydroxy-5,6,4'-trimethox- yflavone by extensive 1D and 2D NMR spectroscopy, a flavonoid exhibiting antioxidative activity with an inhibitory percentage of 25.506% ± 0.205% and inhibition concentration (IC<sub>50</sub>) of 221 μg/ml (R<sup>2</sup> = 0.966, P < 0.01). This is the first time that 7-hydroxy-5,6,4'-trimethoxyflavone is being isolated from L. rugosa and its antioxidant activity evaluated.
基金supported by the National Natural Science Foundation of China (39800093)the Youth Project of Northwest A&F University, China+1 种基金the Innovative Project for University Students of Ministry of Education of Chinathe Key Technologies R&D Program of China during the 11th Five-Year Plan period (2007BAD89B16)
文摘Chicken manures added with Cu and Zn were used for composting experiment to study the dynamics of different soluble humus complexed copper (H2O-Cu,NaOH-Cu and NaOH-Na4P2O7-Cu).The effect of zinc in compost on humus complexed copper and the relationship between humus complexed copper were also revealed.The results showed that H2O-Cu increased before the 45 d of composting and decreased thereafter.In the treatments of 1:1,2:1 and 3:1 with the added copper content increasing,H2O-Cu increased with decomposition process.Added high level zinc in manure could decrease the relative H2O-Cu content at the last stage of composting.NaOH-Cu decreased greatly with the compost proceeding.With the added copper content increasing in manure,the percentage of NaOH-Cu to total copper decreased.Added zinc had no significant impact on NaOH-Cu concentration.NaOH-Na4P2O7-Cu increased with composting.With the added copper content increasing in compost manure,the percentage of NaOH-Na4P2O7-Cu to total copper increased,and showed an increase trend with composting proceeding.Added zinc in manure increased NaOH-Na4P2O7-Cu.In composts,55-80% of extracted copper was present in NaOH fraction,10-30% in NaOH-Na4P2O7-Cu fraction,and 0-10% in H2O fraction.Whatever the added copper or zinc contents increased in manures,the distribution percent of NaOH- Na4P2O7-Cu (pressed as percent of extracted Cu) increased and that of H2O-Cu and NaOH-Cu decreased.Three extracted Cu (H2O,NaOH and Na4P2O7) were strongly correlated to each other,H2O-Cu and NaOH-Na4P2O7-Cu were significantly correlated to H2O-extracted organic C and NaOH-Na4P2O7-extracted organic C,respectively.
基金supported by the National Natural Science Foundation of China(General Program,No.41972127)the National Key Research and Development Program of China(No.2021YFA0719000)。
文摘Comprehensive nitrogen biogeochemical cycle has been reconstructed for representative lacustrine organic-rich sedimentary rock in China,namely the Triassic Yanchang Formation(YF,199–230 Ma)in Ordos and the Cretaceous Qingshankou Formation(QF,86–92 Ma)in Songliao basins,by evaluating the organic and inorganic nitrogen isotopic compositions rather than only organic or bulk nitrogen isotopic compositions.The results indicate that the nitrogen isotope values of bulk rock(δ^(15)N_(bulk))in the non-metamorphic stage are significantly different from that of kerogen,which challenge the conceptual framework of sedimentary nitrogen isotope interpretation.Theδ^(15)N_(bulk)from the YF and QF were lower than their respective the nitrogen isotope values of kerogen(δ^(15)N_(ker)),with offsets up to5.1‰,which have the inverse relationship for the metamorphosed rock.Thermal evolution did not significantly modify the d15N of bulk rock and kerogen.The d15N of sediments from the YF(δ^(15)N_(bulk),1.6‰–5.6‰)were lower than that of rock from the QF(δ^(15)N_(bulk),10.2‰–15.3‰).The nitrogen isotope values of silicate incorporated nitrogen(δ^(15)N_(sil))were slightly lower than those of the d15Nker in the YF and obviously lower for the QF.The fact that different nitrogen cycles occur in the YF and QF due to the different depositional redox conditions leads to different isotopic results.The YF water environment dominated by oxic conditions is not conducive to the occurrence of denitrification and anammox,and no abundant N2 loss leads to the relatively lightδ^(15)N_(bulk).In the stratified water for the QF,redox transition zone promotes denitrification and anammox,resulting in the heavyδ^(15)N_(bulk)of rock and promotes the DNRA,resulting in heavyδ^(15)N_(ker)and lowδ^(15)N_(sil).
基金supported by the National Key Research Program of China(Nos.2016YFD0200107and 2016YFD0300802)the National Natural Science Foundation of China(No.41271311)+1 种基金the Earmarked Fund for China Agriculture Research System(No.CARS-03)the Science and Technology Service Network Initiative of Chinese Academy of Sciences(Nos.KFJ-SW-STS-142-03 and KFJ-EW-STS-083-2)
文摘Investigating the effects of residue chemical composition on soil labile organic carbon (LOC) will improve our understanding of soil carbon sequestration. The effects of maize residue chemical composition and soil water content on soil LOC fractions and microbial properties were investigated in a laboratory incubation experiment. Maize shoot and root residues were incorporated into soil at 40% and 70% field capacity. The soils were incubated at 20 ℃ for 150 d and destructive sampling was conducted after 15, 75, and 150 d. Respiration, dissolved organic carbon (DOC), hot-water extractable organic carbon (HEOC), and microbial biomass carbon (MBC) were recorded, along with cellulase and β-glucosidase activities and community-level physiological profiles. The results showed that the cumulative respiration was lower in root-amended soils than in shoot-amended soils, indicating that root amendment may be beneficial to C retention in soil. No significant differences in the contents of DOG, HEOC and MBC, enzyme activities, and microbial functional diversity were observed between shoot- and root-amended soils. The high soil water content treatment significantly increased the cumulative respiration, DOC and HEOC contents, and enzyme activities compared to the low soil water content treatment. However, the soil water content treatments had little influence on the MBC content and microbial functional diversity. There were significantly positive correlations between LOC fractions and soil microbial properties. These results indicated that the chemical composition of maize residues had little influence on the DOC, HEOC, and MBC contents, enzyme activities, and microbial functional diversity, while soil water content could significantly influence DOC and HEOC contents and enzyme activities.
基金Project supported by National Natural Science Foundation of China(51604128)
文摘To examine the activation of organic acids on the leaching process of ion-adsorption type rare earth ore(IRE-ore), the leaching behavior of rare earth(RE) and zeta potential of IRE-ore were investigated in the absence and presence of carboxylic acids. The results show that all the tested organic acids(acetic acid,malonic acid, citric acid, tartaric acid, succinic acid, and malic acid) can promote RE extraction. At relatively high concentrations of organic acids, the activation efficiency of organic acids on RE extraction is generally consistent with their complexation ability; whereas at their low concentrations, the change of zeta potential on the IRE-ore surface with organic acid concentration and p H has a close association with RE extraction, which indicates that organic acids can impact the surface electrical property of IREore via their adsorption/desorption, and thereby increase/decrease the affinity of RE ions to IRE-ore.Therefore the influence of organic acids on the IRE-ore surface electrical property also plays an important role in RE extraction in addition to their complexation with RE ions.
文摘In most organics extraction processes, the commonly used solvents employ solely physical interactions. Therefore, for the recovery and purification of products from complex mixtures, the selectivity and/or capacity of classical solvents towards the desired solutes is usually insufficient, enforcing the need for complex and thus expensive separation schemes. Significant simplification and cost-reduction can be achieved when affinity solvents would be available that are able to recognize the solutes of interest by their molecular structure. The main development challenges to establish such affinity solvents are: Selection and incorporation of molecular recognition and complexation capabilities; Evaluation of extraction capabilities; Efficient re- covery and recycling of the affinity solvents; Implementation in industrial extraction equipment. This paper presents how these development challenges are addressed at the University of Twente, going all the way from affinity solvent design and synthesis, via high throughput screening and characterization up to pilot plant evaluation. Essential in the successful development of affinity solvents are structural cooperations with molecular chemists and custom synthesis companies for their design and synthesis. The various aspects are illustrated by several examples where newly developed environmentally benign affinity solvents appeared able to create major breakthroughs. The applications addressed involve oxygenates, sugars, and pharmaceutical ingredients, such as optical isomers and biomolecules.
基金supported by the National Natural Science Foundation of China (No. 21507146)the special fund from the State Key Joint Laboratory of Environment Simulation and Pollution Control (Research Center for Eco-environmental Sciences, Chinese Academy of Sciences) (No. 15Z01ESPCR)
文摘Solution ^(31)P nuclear magnetic resonance spectroscopy( ^(31)P-NMR) is a useful method to analyze organic phosphorus(Po), but a general procedure for the analysis method is lacking.The authors used solution ^(31)P-NMR, which was found to be an effective method for analysis of Po in Haihe River sediment, to analyze the Po in the surface sediment in Eastern China at the regional scale, and found that the Na OH-ethylenediaminetetraacetic acid(EDTA)extraction rate was affected by environmental factors. At the regional scale, the extraction rate showed a positive relationship with loss on ignition, when the extraction rate was lower than 60%. The extraction rate had no relationship with the loss on ignition when the extraction rate was higher than 60%. The extraction rate showed a negative relationship with p H, which means that the extraction rate was higher in acidic sediment and lower in alkaline sediment. The ratio of TC/TN(the ratio of total carbon to total nitrogen) was considered to represent the origin of organic matter in the sediment. The extraction rate was high when the TC/TN ratio was lower than 20, meanwhile the extraction rate decreased as the TC/TN ratio increased. The results show that the origin of organic matter in sediment significantly affects the Na OH-EDTA extraction rate. This study will give theoretical support for building an effective and general solution ^(31)P-NMR analysis method.
文摘The toxicity of soil irrigated with treated domestic wastewater (site A) and untreated gray wastewater (site B) were investigated. Soil extracts were prepared using distilled water, acid solvent (0.1 mol·L-1 HCl), and organic solvent (acetone:petroleum ether:cyclohexane= 1:1:1) to understand the type of pollutants responsible for the ecotoxicity associated with wastewater irrigation. The soil toxicity was assessed using a luminescence inhibition assay with Vibrio fischeri for acute toxicity, a micronucleus assay with Vicia faba root tips and a single cell gel electrophoresis assay of mice lymphocytes for genotoxicity. The physicochemical properties and the heavy metal (HM) contents of the irrigated soil were also analyzed. The results indicated that the wastewater irrigation at site A had no effects on the soil properties. With the exception of Pb, Zn, Fe, and Mn, the accumulation of HMs (Cu, Ni, and Cr) occurred. However, the irrigation at site A did not result in obvious acute toxicity or genotoxicity in the soil. The soil properties changed greatly, and HMs (Cu, Ni, and Cr) accumulated in site B. There were significant increases in the acute toxic and genotoxic effects in the soils from site B. The ecotoxicity in site B came primarily from organic-extractable pollutants.
基金Supported by the National Basic Research Program(973 Program)of China(No.2011CB100503)the National Natural Science Foundation of China(No.21007027)+1 种基金the Qing Lan Project of Jiangsu Province,Chinathe National"111"Project of China’s Higher Education(No.B12009)
文摘To better understand the role of organic matter(OM)prepared from chicken manure and agriculture residues compost on the growth of plants(Lepidium sativum L.)and antagonistic fungi(Trichoderma harzianum),we analyzed the structure and composition of extracted OM using fluorescence excitation-emission matrix(EEM)spectroscopy and solid-state13C cross-polarization magic-anglespinning nuclear magnetic resonance(13C CPMAS NMR)spectroscopy.The results showed that the EEM contours of water-extracted OM(WEOM)and alkali-extracted OM(AEOM)were similar.Furthermore,solid-state13C CPMAS NMR spectroscopy demonstrated that water extraction could not proportionally pull out aromatic moieties(112–145 ppm)from compost,but the alkali method in proportion extracted both carbohydrates(65–85 ppm)and aromatic moieties.The results suggest that AEOM may better reflect the bulk OM composition of compost,and one should be cautious when applying WEOM as an alternative indicator of total compost OM.Further investigations demonstrated that,compared to carbohydrates,aromatic moieties played a predominant role in growth suppression of Lepidium sativum L.seeds and Trichoderma harzianum.
基金supported by the National Natural Science Foundation of China(Nos.41401565,41201520 and 20807046)
文摘Bioavailability is a critical factor for assessing the environmental risk of organic pollutants in soil. In this study, extractions with 3 different solvents, including 2 aqueous solutions, calcium chloride(CaCl_2) and a phosphate buffer solution(PBS), and a mixture of aqueous solution and organic solvent, a PBS-methanol(8:2,volume/volume) mixture(PBS-M), were performed to assess the bioavailability of chlorimuron-ethyl in soil in comparison to a battery of toxicity tests in wheat seedlings. The results indicated that the peroxidase(POD) activity in wheat leaves after 7 d of exposure was one of the sensitive biomarkers of chlorimuron-ethyl in soil.The extractability of chlorimuron-ethyl by all the 3 solvents decreased with exposure time, and the rate of decrease of the PBS-M extraction between 1 and 7 d of exposure was substantially higher than those of the aqueous solution extractions. Chlorimuron-ethyl gradually changed from a water-soluble form into a soil organic matter(SOM)-bound form in the soil. The PBS extraction correlated best with the POD activity in the leaves after 7 d of exposure.
基金supported by Tianjin Research Program of Application Foundation and Advanced Technology(No.14JCZDJC40500)National Undergraduate Innovation Program(No.2016100570039).
文摘In this study,allelochemicals were extracted from pulping effluents rather than from the raw ma-terial of plants.Herein,five organic solvents(ethyl acetate(EAC),methyl tert-butyl ether(MTBE),dichloromethane(DCM),carbon tetrachloride(CTC),and petroleum(PE))were applied to sep-arately extracting the allelochemicals from alkaline peroxide mechanical pulp(APMP)effluents.The results from the algal density,inhibition ratio,and optical density of 446 nm(OD 446nm)concluded that the extractives from the APMP effluents can act as effective allelochemicals and showed noticeable allelopathic inhibition effects on Microcystis aeruginosa growth.The results in-dicated that organic solvent extraction could be a practical approach to isolate the allelochemicals from the APMP effluents,which would broaden the potential application of the APMP effluents in the production of antimicrobial agents and other value-added materials.