Time filter

Source Type

Li N.,CAS Tianjin Institute of Industrial Biotechnology | Zhao L.,Agro Environmental Protection Institute | Zhao L.,Tianjin Key Laboratory of Agro Environment and Agro Product Safety | Ng T.B.,Chinese University of Hong Kong | And 4 more authors.
Applied Microbiology and Biotechnology | Year: 2015

A new molecularly imprinted polymer (MIP), prepared by hispidin as the template molecule, was synthesized and applied as an adsorbent phase for solid phase extraction (SPE) to isolate and enrich hispidin from eight species of mushrooms. The optimization of synthesis and the adsorption behaviors of the MIPs were investigated in detail. In comparison with C18-SPE, MIP-SPE displayed high selectivity and good affinity for hispidin for extract of Phellinus igniarius. The antioxidant activity of the extracts after using the MIPs was evaluated by free radical scavenging activity, and inhibition of erythrocyte hemolysis, and lipid peroxidation. This developed method provided a rapid, selective, and effective approach for separation and enrichment of active compounds from the natural products. © 2015, Springer-Verlag Berlin Heidelberg.


Zheng S.-A.,Agro Environmental Protection Institute | Zheng S.-A.,Key Laboratory of Production Environment and Agro Product Safety | Zheng S.-A.,Tianjin Key Laboratory of Agro Environment and Agro Product Safety | Zheng X.,Agro Environmental Protection Institute | And 9 more authors.
Fresenius Environmental Bulletin | Year: 2012

Effect of wastewater irrigation on the changes of some soil properties, distribution and fractionation of heavy metals (Cu, Pb and Cd) in soil profiles was investigated by monitoring different plots from Pengzhou, China, which had been irrigated with wastewater for varying periods of time (5, 12 and 20 years, respectively). The non-wastewaterirrigated plot served as the control. Total concentrations of heavy metals at different soil depths were analyzed by acid digestion, and their fractions were partitioned by a sequential extraction procedure, where the speciation of metals was experimentally defined as exchangeable, carbonate-, Fe-Mn oxide-, organic matter-bound and residual fraction. Results showed that soil pH values were significantly (p < 0.05) lowered in plots with more than 12-year irrigation to a depth of 80 cm, while electrical conductivity was elevated for all three plots compared with control, and soil organic matter increased in top 40 cm layers in plots with 12- and 20-year wastewater irrigation. Longterm irrigation with wastewater (12 and 20 years) has led to significant increases in heavy metals' total amounts in surface layer (0-40 cm), in which it also resulted in a marked increase in heavy metal concentrations in the all non-residual fractions, and correspondingly affected the relative binding capacity of heavy metals (except for Pb in soil profile from plot with 20-year irrigation). It was also found that the amounts of heavy metals in residual fractions kept almost unchanged in all plots. The study concludes that long-term wastewater irrigation might give rise to the accumulation and mobilization of heavy metals in upper soil horizons, which may limit the use of wastewater for landscape and agriculture. © by PSP.


Zheng S.,Zhejiang University | Zheng S.,Agro Environmental Protection Institute | Zheng S.,Key Laboratory of Production Environment and Agro product Safety | Zheng S.,Tianjin Key Laboratory of Agro environment and Agro product Safety | Zhang M.,Zhejiang University
Journal of Environmental Sciences | Year: 2011

Sequential extraction procedure was applied to assess the dynamics of solid-phase transformation of added Cu, Pb, Cd, and Hg in a typical Chinese paddy soil incubated under three moisture regimes (75% field capacity, wetting-drying cycle, and flooding). The heavy metals spiked in the soil were time-dependently transferred from the easily extractable fraction (the exchangeable fraction) into less labile fractions (Fe-Mn oxide- and organic matter-bound fractions), and thus reduced lability of the metals. No significant changes were found for the carbonate-bound and residual fractions of the heavy metals in the soil during the whole incubation. Change rate of the mobility factor (MF), a proportion of weakly bound fractions (exchangeable and carbonate-bound) in the total metal of soil, reflected the transformation rate of metal speciation from the labile fractions toward stable fractions. It was found that soil moisture regime did not change the direction and pathways of transformation of metal speciation, but it significantly affected the transformation rate. In general, the paddy soil under flooding regime had higher metal reactivity compared with 75% field capacity and wetting-drying cycle regimes, resulting in the more complete movement of metals toward stable fractions. This might be related to the increased pH, precipitation of the metals with sulfides and higher concentration of amorphous Fe oxides under submerged condition. © 2011 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences.


Zhang K.,Agro Environmental Protection Institute | Zhang K.,Key Laboratory of Production Environment and Agro Product Safety | Zhang K.,Tianjin Key Laboratory of Agro Environment and Agro Product Safety | An Y.,Agro Environmental Protection Institute | And 6 more authors.
Chemosphere | Year: 2012

Nano-MgO is a good bactericide but with strong alkalinity in water due to its rapid hydrolysis. To control its hydrolysis rate and keep its bactericidal properties, we synthesized nano-MgO microspheres using chitosan-alginate system in this study. The synthesized nano-MgO release-controlled microspheres (nMgO-RCM) were with 0.98-1.20mm of particle sizes. Also, their embedding ratio and loading percentage was 63.52% and 12.27%, respectively. Based on the characterization results, nano-MgO was only observed on surface of the nMgO-RCM. Its release rate from the nMgO-RCM could be controlled by the chitosan-alginate system, and the observed rate constant (kobs) increased from 0.0289h-1 to 0.0358h-1 with the increment of the dosage from 10mgL-1 to 80mgL-1. Furthermore, the nMgO-RCM could maintain pH value lower than 8.5 and colony counts less than 20CFUmL-1 for at least 120h. © 2012 Elsevier Ltd.


Zheng S.-a.,Agro Environmental Protection Institute | Zheng S.-a.,Key Laboratory of Production Environment and Agro Product Safety | Zheng S.-a.,Tianjin Key Laboratory of Agro Environment and Agro Product Safety | Zheng X.,Agro Environmental Protection Institute | And 5 more authors.
PLoS ONE | Year: 2012

Heavy metals that leach from contaminated soils under acid rain are of increasing concern. In this study, simulated acid rain (SAR) was pumped through columns of artificially contaminated purple soil. Column leaching tests and sequential extraction were conducted for the heavy metals Cu, Pb, Cd, and Zn to determine the extent of their leaching as well as to examine the transformation of their speciation in the artificially contaminated soil columns. Results showed that the maximum leachate concentrations of Cu, Pb, Cd, and Zn were less than those specified in the Chinese Quality Standards for Groundwater (Grade IV), thereby suggesting that the heavy metals that leached from the polluted purple soil receiving acid rain may not pose as risks to water quality. Most of the Pb and Cd leachate concentrations were below their detection limits. By contrast, higher Cu and Zn leachate concentrations were found because they were released by the soil in larger amounts as compared with those of Pb and Cd. The differences in the Cu and Zn leachate concentrations between the controls (SAR at pH 5.6) and the treatments (SAR at pH 3.0 and 4.5) were significant. Similar trends were observed in the total leached amounts of Cu and Zn. The proportions of Cu, Pb, Cd, and Zn in the EXC and OX fractions were generally increased after the leaching experiment at three pH levels, whereas those of the RES, OM, and CAR fractions were slightly decreased. Acid rain favors the leaching of heavy metals from the contaminated purple soil and makes the heavy metal fractions become more labile. Moreover, a pH decrease from 5.6 to 3.0 significantly enhanced such effects. © 2012 Zheng et al.


Liang X.,Agro Environmental Protection Institute | Liang X.,Tianjin Key Laboratory of Agro Environment and Agro Product Safety | Xu Y.,Agro Environmental Protection Institute | Xu Y.,Tianjin Key Laboratory of Agro Environment and Agro Product Safety | And 10 more authors.
Chemosphere | Year: 2013

Mercapto functionalized sepiolite (MSEP) was prepared by nanotexturization method and applied for the sorption of Pb2+ from aqueous solution. These samples before and after sorption were characterized through XRD, FT-IR, 29Si and 13C CP/MAS NMR and XPS. The sorption behaviors including thermodynamic and kinetic parameters, effect factors and mechanisms of Pb2+ sorption on MSEP were studied. The maximum sorption amounts of 97mgg-1. The parameters ΔH0 and ΔS0 were 33.637kJmol-1 and 202.697Jmol-1K-1, respectively. Freundlich isotherm was proved to describe the sorption data better than other isotherms and pseudo second order kinetic model could fit the sorption kinetic processes well. The pH influenced the sorption of Pb2+ on MSEP significantly but background electrolytes have relative weak effect. Based on hard and soft acids and bases theory and the results analyzed from XPS, the sorption mechanisms could be explained as primarily chemical adsorption and secondary physical adsorption. © 2012 Elsevier Ltd.


An Y.,Agro Environmental Protection Institute | An Y.,Key Laboratory of Production Environment and Agro product Safety | An Y.,Tianjin Key Laboratory of Agro environment and Agro product Safety | Dong Q.,Agro Environmental Protection Institute | And 5 more authors.
Chemosphere | Year: 2014

Hydrogenotrophic bacteria (HTB) were introduced into a nitrate removal system, which used nanoscale zero-valent iron (nZVI) as reductant, to investigate its bioinhibitory effect. Based on the results, it was noted that addition of HTB culture (10-50mL) led to 58.9-91.4% decrease in the first observed rate constant (kobs1), which represented the nitrate removal rate by nZVI, and a reduction in the generated poisonous by-products from 94.9% to 38.5%. In other words, HTB had a significant inhibitory effect on nitrate reduction by nZVI. However, the pathway of this bioinhibition only prevented the occurrence of chemical reduction, but not competition for nitrate. Furthermore, FeOOH coating was observed on the surface of nZVI, instead of Fe3O4 or Fe2O3, which could prevent electron transmission from nZVI to nitrate. Considering that FeOOH was the product of iron corrosion, the result indicated that HTB could inhibit chemical reduction by enhancing the reaction between nZVI and water. © 2013 Elsevier Ltd.


An Y.,Agro Environmental Protection Institute | Zhang K.,Key Laboratory of Production Environment and Agro product Safety | Dong Q.,Tianjin Key Laboratory of Agro environment and Agro product Safety | Zhang L.,Tianjin University
Water Science and Technology | Year: 2013

An integrated nitrate treatment using passivated iron powder (PIP) and Alcaligenes eutrophus, which is a kind of hydrogenotrophic denitrifying bacteria, was conducted to investigate the effect of iron oxide coating on final-product distribution in hydrogenotrophic denitrification. Based on the results, the autotrophic denitrification supported by PIP could completely remove about 50 mg·L1 of nitrate within 4 days, and almost 80% of nitrate was changed into N2O (under acetylene blocking) without residual nitrite or ammonium. While only 53% of the nitrate was removed using acid-washed iron (AWI) instead of PIP, about 70% was converted into ammonium. Furthermore, a layer of FeOOH converted from hematite (α-Fe2O3) and magnetite (Fe3O4), which may block direct chemical nitrate reduction, was observed on the iron surface when PIP was used to support hydrogenotrophic denitrification. In addition, increasing pH from 5 to 8 increased nitrite generation from 1.19 to 4.91%, and decreased ammonium formation from 4.23 to 0%. Copyright © IWA Publishing 2013 Water Science and Technology.


Liang X.,Tianjin University | Liang X.,Agro Environmental Protection Institute | Liang X.,Tianjin Key Laboratory of Agro Environment and Agro Product Safety | Zang Y.,Shangqiu Normal University | And 8 more authors.
Colloids and Surfaces A: Physicochemical and Engineering Aspects | Year: 2013

Layered double hydroxides (LDHs) are a class of ionic lamellar compounds made up of positively charged brucite-like layers with an interlayer region containing charge compensating anions and solvation molecules. In recent years, many studies have focused on the application of LDHs in environmental remediation of anion pollutant. Meanwhile many reports are devoted to investigating the ability of LDHs to remove metal cations such as Pb2+, Cd2+ and Cu2+ from aqueous solutions. This paper provides an overview of the recent advances achieved in sorption of metal cations on LDHs. Sorption behaviors of various cations on LDHs including sorption isotherms and kinetics have been comprehensively reviewed. Several essential factors such as pH, temperature, ionic strength that influence the sorption are discussed. The sorption mechanisms including precipitation, surface complexation, isomorphic substitution and chelation with the anions in the interlayer of LDHs are discussed in detail. Possible improvement and potential applications of LDHs in the future are also proposed. © 2013 Elsevier B.V.


Liang X.,Tianjin University | Liang X.,Agro Environmental Protection Institute | Liang X.,Tianjin Key Laboratory of Agro Environment and Agro Product Safety | Xu Y.,Agro Environmental Protection Institute | And 12 more authors.
Colloids and Surfaces A: Physicochemical and Engineering Aspects | Year: 2013

Palygorskite was functionalized by mercapto and amino groups respectively in the high-speed shear process based on the rheological properties to enhance its sorption amounts and selectivity for heavy metals. The mercapto and amino functionalized samples were characterized through solid-state 29Si CP/MAS NMR, TEM, SEM, TG, XRD, surface area analysis and zeta potentials. The surface modification took place in the high-speed shear process between the silanol groups of palygorskite and organosilanes. The reaction produced a continuous coating of individual fibers of palygorskite. The crystal structure of palygorskite did not change significantly after surface modification. The isoelectric points shifted to lower pH values and the surface areas decreased due to the bulk size of the functional ligands. The sorption of Pb2+, Cd2+ and Cu2+ on the samples was studied in batch experiments and it was found that the surface modification could obviously increase the sorption capacities for Pb2+, Cd2+ and Cu2+. The mercapto and amino functionalized palygorskite could provide a potential remedy for heavy metal contamination in aqueous environment. © 2013 Elsevier B.V.

Loading Tianjin Key Laboratory of Agro Environment and Agro Product Safety collaborators
Loading Tianjin Key Laboratory of Agro Environment and Agro Product Safety collaborators