A series of phosphorus-modified titanium dioxide samples with varying P/Ti atomic ratio were conveniently prepared via a conventional solgel route. The effects of phosphorus content and calcination temperature on the ...A series of phosphorus-modified titanium dioxide samples with varying P/Ti atomic ratio were conveniently prepared via a conventional solgel route. The effects of phosphorus content and calcination temperature on the crystalline structure, grain growth, surface area, and the photocatalytic activity of P-modified TiO2 were investigated. The XRD results showed that P species slow down the particle growth of anatase and increase the anatase-to-rutile phase transformation temperature to more than 900°C. Kinetic studies on the P-modified TiO2 to degraded 4-chlorophenol had found that the TP5500 prepared by adopting a P/Ti atomic ratio equal to 0.05 and calcined at 500°C had an apparent rate constant equal to 0.0075 min 1, which is superior to the performance of a commercial photocatalyst Degussa P25 Kapp = 0.0045 min 1 and of unmodified TiO2 （TP0500） Kapp = 0.0022 min 1. From HPLC analyses, various hydroxylated intermediates formed during oxidation had been identified, including hydroquinone （HQ）, benzoquinone （BQ） and （4CC） 4-chlorocatechol as main products. Phytotoxicity was assessed before and after irradiation against seed germination of tomato （Lycopersicon esculentum） whereas acute toxicity was assessed by using Folsomia candida as the test organism. Intermediates products were all less toxic than 4-chlorophenol and a significant removal of the overall toxicity was accomplished展开更多
This study investigated the effects of biochar(BC),H_(3)PO_(4)-modified biochar(BP)and KH_(2)PO_(4)-modified biochar(BK)on heavy metals(HMs)passivation and the distribution of antibiotic resistance genes(ARGs)and meta...This study investigated the effects of biochar(BC),H_(3)PO_(4)-modified biochar(BP)and KH_(2)PO_(4)-modified biochar(BK)on heavy metals(HMs)passivation and the distribution of antibiotic resistance genes(ARGs)and metal resistance genes(MRGs)during anaerobic digestion(AD).Characterization results revealed that the application of BK significantly decreased the mobility of Cr,Cu,and Pb,attributing to metal phosphate precipitation formation.EEM-PARAFAC and 2D-FTIR-COS analysis showed that the C-O stretching,polysaccharide-like structures,N-contain substance or carboxylic reacted faster after adding biochar.Biochar addition promoted the synthesis of fluorescent and humic-like components,and accelerated humification process,thus showing a greater complexation ability for HMs.In BK treatments,most detected ARGs abundance were reduced with efficiencies of 85%–96%,and MRGs abundance,such as phrT,yieF,chrR,etc.,were significantly declined by more than 90%.Biochar addition directly reduced MRGs abundance by improving the immobilization degree of HMs.Biochar addition inhibited horizontal gene transfer(HGT)facilitated by mobile genetic elements(MGEs)and reduced co-selective pressure by HMs,thereby decreasing ARGs abundance.Biochar stimulated growth of HMs tolerant bacteria,such as Bacillus,Romboutsia,Clostridiales,etc.,which functioned well in HMs immobilization.P-loaded biochar as additive is recommended in AD to mitigate ARGs distribution and reduce HMs risks.展开更多
Phosphorus(P)-modified biochar demonstrates dual capabilities for heavy metal immobilization and soil quality enhancement.However,the underlying mechanism of microbial response to changes in soil properties is still u...Phosphorus(P)-modified biochar demonstrates dual capabilities for heavy metal immobilization and soil quality enhancement.However,the underlying mechanism of microbial response to changes in soil properties is still unclear.In this study,P-modified biochar,prepared by co-pyrolysis of apple tree branches with K_(3)PO_(4),was used for removal of heavy metals from the soils near a mining area.Effects of P-modified biochar on the microbial communities in soil were investigated and the key driving factors were identified.Adding P-modified biochar reduced the bioavailable cadmium and lead contents of the soil by 28.21%and 28.64%,respectively,mainly through improved co-precipitation and cation exchange.In turn,the cadmium and lead concentrations in maize grains were reduced by 36.52%and 61.82%respectively.Meanwhile,the richness and diversity of soil bacteria significantly decreased with the addition of P-modified biochar(P<0.05).Microbial multi-trophic ecological network module analysis and partial least squares pathway modeling indicated that biochar changed the capacity of the soil to provide microorganisms with nitrogen and P,requiring the key microbial taxa(modules 1 and 3)to adjust.Modules 1 and 3 played important but opposite functions in the nitrogen and P cycle of the soil.This further led to variations in the composition and structure of microbial communities in soil.Particularly,changes in the bioavailability of heavy metals showed a negligible effect on soil microbial communities.This study emphasizes that P-modified biochar can efficiently reduce soil heavy metal bioavailability and alter the microbial community by regulating nutrient supply balance.展开更多
文摘A series of phosphorus-modified titanium dioxide samples with varying P/Ti atomic ratio were conveniently prepared via a conventional solgel route. The effects of phosphorus content and calcination temperature on the crystalline structure, grain growth, surface area, and the photocatalytic activity of P-modified TiO2 were investigated. The XRD results showed that P species slow down the particle growth of anatase and increase the anatase-to-rutile phase transformation temperature to more than 900°C. Kinetic studies on the P-modified TiO2 to degraded 4-chlorophenol had found that the TP5500 prepared by adopting a P/Ti atomic ratio equal to 0.05 and calcined at 500°C had an apparent rate constant equal to 0.0075 min 1, which is superior to the performance of a commercial photocatalyst Degussa P25 Kapp = 0.0045 min 1 and of unmodified TiO2 （TP0500） Kapp = 0.0022 min 1. From HPLC analyses, various hydroxylated intermediates formed during oxidation had been identified, including hydroquinone （HQ）, benzoquinone （BQ） and （4CC） 4-chlorocatechol as main products. Phytotoxicity was assessed before and after irradiation against seed germination of tomato （Lycopersicon esculentum） whereas acute toxicity was assessed by using Folsomia candida as the test organism. Intermediates products were all less toxic than 4-chlorophenol and a significant removal of the overall toxicity was accomplished
基金funded by the National Natural Science Foundation of China(No.52300164)the Shandong Provincial Natural Science Foundation,China(No.ZR2024QE365)+4 种基金the Science Foundation of National Engineering Research Center for Safe Disposal and Resources Recovery of Sludge(Harbin Institute of Technology,China,No.K2024A008)the Technological Project of Heilongjiang Province“the open competition mechanism to select the best candidates”,China(No.2022ZXJ05C01-03-01)the Key R&D Program of Heilongjiang Province,China(No.2022ZX02C16)the State Key Laboratory of Urban Water Resource and Environment at Harbin Institute of Technology,China(No.2023DX05)the National Engineering Research Center for Sludge Safe Disposal,China(No.Z2024A002).
文摘This study investigated the effects of biochar(BC),H_(3)PO_(4)-modified biochar(BP)and KH_(2)PO_(4)-modified biochar(BK)on heavy metals(HMs)passivation and the distribution of antibiotic resistance genes(ARGs)and metal resistance genes(MRGs)during anaerobic digestion(AD).Characterization results revealed that the application of BK significantly decreased the mobility of Cr,Cu,and Pb,attributing to metal phosphate precipitation formation.EEM-PARAFAC and 2D-FTIR-COS analysis showed that the C-O stretching,polysaccharide-like structures,N-contain substance or carboxylic reacted faster after adding biochar.Biochar addition promoted the synthesis of fluorescent and humic-like components,and accelerated humification process,thus showing a greater complexation ability for HMs.In BK treatments,most detected ARGs abundance were reduced with efficiencies of 85%–96%,and MRGs abundance,such as phrT,yieF,chrR,etc.,were significantly declined by more than 90%.Biochar addition directly reduced MRGs abundance by improving the immobilization degree of HMs.Biochar addition inhibited horizontal gene transfer(HGT)facilitated by mobile genetic elements(MGEs)and reduced co-selective pressure by HMs,thereby decreasing ARGs abundance.Biochar stimulated growth of HMs tolerant bacteria,such as Bacillus,Romboutsia,Clostridiales,etc.,which functioned well in HMs immobilization.P-loaded biochar as additive is recommended in AD to mitigate ARGs distribution and reduce HMs risks.
基金funded by Agricultural Key-scientific and Core-technological Project of Shaanxi Province(2024NYGG011-5)Shaanxi Province Key Research and Development Plan Project(2024NC-YBXM-235)+2 种基金Shaanxi Province Agricultural Science and Technology Innovation Special Funds Project(K3031223146)Natural Science Foundation Project of Shanxi Province(202103021224142)Introduced Talents Scientific Research Initiation Project Program of Shanxi Agricultural University(2023BQ87,2023BQ121).
文摘Phosphorus(P)-modified biochar demonstrates dual capabilities for heavy metal immobilization and soil quality enhancement.However,the underlying mechanism of microbial response to changes in soil properties is still unclear.In this study,P-modified biochar,prepared by co-pyrolysis of apple tree branches with K_(3)PO_(4),was used for removal of heavy metals from the soils near a mining area.Effects of P-modified biochar on the microbial communities in soil were investigated and the key driving factors were identified.Adding P-modified biochar reduced the bioavailable cadmium and lead contents of the soil by 28.21%and 28.64%,respectively,mainly through improved co-precipitation and cation exchange.In turn,the cadmium and lead concentrations in maize grains were reduced by 36.52%and 61.82%respectively.Meanwhile,the richness and diversity of soil bacteria significantly decreased with the addition of P-modified biochar(P<0.05).Microbial multi-trophic ecological network module analysis and partial least squares pathway modeling indicated that biochar changed the capacity of the soil to provide microorganisms with nitrogen and P,requiring the key microbial taxa(modules 1 and 3)to adjust.Modules 1 and 3 played important but opposite functions in the nitrogen and P cycle of the soil.This further led to variations in the composition and structure of microbial communities in soil.Particularly,changes in the bioavailability of heavy metals showed a negligible effect on soil microbial communities.This study emphasizes that P-modified biochar can efficiently reduce soil heavy metal bioavailability and alter the microbial community by regulating nutrient supply balance.
