BIORESOURCE TECHNOLOGY
·
2024
·
IF 9.7
Ming Xu,Hao-qiang Chen,Peng Gao,Xiao-xiao Shen
This study explores the roles of fulvic acid (FA) in both a conventionally constructed wetland (CCW) and a newly constructed wetland – microbial electrolysis cell (ECW). The results showed that FA increased the average removal efficiency of chemical oxygen demand, total phosphorus, total nitrogen, and ammonia nitrogen in ECW by 8.6, 46.2, 33.0, and 27.9 %, respectively, compared to CCW, and reduced the global warming potential by > 60 %. FA promoted the proliferation of electroactive bacteria (e.g., Chlorobaculum and Candidatus Tenderia ) and FA-degrading bacteria (e.g., Anaerolineaceae and Gammaproteobacteria) and reduced methanogens (e.g., Methanothrix ) via type-changing. The study’s findings suggest that FA influences pollutant removal and microbiome dynamics by altering dissolved oxygen levels and redox potential. In summary, FA and ECW enhanced the efficiency of constructed wetlands by facilitating electron transfer and consumption, and supporting microbial growth and metabolism.
研究领域:
环境科学
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF NANOPARTICLE RESEARCH
·
2015
·Vol. 17
·期 11
·1-11
·
IF 2.184
He Guang’an,Chen Rui,Lu Shushen,Jiang Chengchun,Liu Hong,Wang Chuan
The predictable significant increase in manufacture and use of engineered nanoparticles (ENPs) will cause their inevitable release into environment, and the potential harmful effects of ENPs have been confirmed. As representative ENPs, sedimentation behavior of nano-titanium dioxide (n-TiO 2 ) should be better understood to control its environmental risk. In this study, an experimental methodology was established to set the sampling area and sampling time of n-TiO 2 sedimentation. In addition, we defined a quasi-stable state and a precise index, i.e., sedimentation efficiency (SE) at this state, to describe the n-TiO 2 sedimentation behavior. Both alternative concentration determination and conventional size measurement were applied to evaluate the sedimentation behavior of n-TiO 2 with fulvic acid. Results showed that the sedimentation behavior described by SE was more precise and in disagreement with those predicted by particle size. Moreover, sedimentation experiments with salicylic acid (SA), under an electric field and different water temperatures or with sulfosalicylic acid under light irradiation were also performed. When the total organic carbon concentration of SA, the voltage of working electrodes, and water temperature increased, or the wavelength of light source decreased, the SE of n-TiO 2 increased and n-TiO 2 showed a tendency to settle in water. These findings might be important for deepening the understanding of n-TiO 2 environmental behavior and exploring sedimentation behavior of other ENPs.
研究领域:
环境科学
·
纳米技术
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Ling Xiong,Liying Ma,Meiqi Zhao,Haojian Zhang,Shaohua Chen
In present work, nanoscale zero-valent iron (nZVI) was successfully stabilized using fulvic acid (nZVI-FA). Shewanella oneidensis MR-1 (MR-1) was used to enhance the reactivity of the nZVI-FA. The results demonstrated that nZVI-FA combined with the MR-1 (nZVI-FA/MR-1) system could effectively solve the aggregation and surface passivation of nZVI, thereby significantly enhancing the reactivity of nZVI for Cr(VI) removal. The Cr(VI) removal efficiency of the nZVI-FA/MR-1 system (100 %) within 24 h was apparently higher than that of the ZVI-FA system (64.43 %). The enhancement of Cr(VI) removal is because fulvic acid (FA) FA can stabilize nZVI against aggregation; MR-1 could rapidly reduce the Fe(III) (hydr)oxides (FeHOs) passivation layers on the surface of nZVI-FA to biogenic Fe(II) [bio-Fe(II)], which in turn reduced Cr(VI). X-ray photoelectron spectroscopy (XPS) analysis revealed that the Fe(II)/Fe(III) ratio (1.20) and Cr(III)/Cr(VI) ratio (2.53) of the precipitates in the nZVI-FA/MR-1 system were much higher than that those in the nZVI-FA system (0.55 and 1.40, respectively). Three-dimensional excitation-emission matrix (3D-EEM) spectral analysis confirmed that tyrosine, tryptophan, and protein-like substances in extracellular polymeric substances (EPSs) from MR-1 are vital for the removal of Cr(VI). The mechanism analysis demonstrated that most Cr(VI) was reduced to Cr(III); Cr(III) existed as Cr 2 O 3 , FeCr 2 O 4 and Cr x Fe 1-x (OH) 3 precipitates, and some of the Cr(VI) was removed from the solution by adsorption and complexation. This study offers a low-cost, efficient, and environmentally friendly strategy to enhance the reactivity of nZVI for Cr(VI) removal, which has broad prospective applications.
研究领域:
环境科学
·
微生物学
✓ 已验证
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2022
·Vol. 46
·期 47
·22877-22888
·
IF 3.925
Qiang Wang,Ying-Rong Wang,Wen-Jing Wei,Hai-Lan Lin,Ping-Jian Yang
Nano-silver (Ag-NPs) has been widely applied due to its antibacterial properties, but issues remain with its toxicity. Although most Ag-NPs in the environment come from artificial import, the natural generation of Ag-NPs has also been discovered. In the present study, the particle characteristics and stability of naturally generated Ag-NPs, which might be different in migration, transformation, and bioavailability of artificially introduced Ag-NPs, were investigated and discussed in detail. Cloud point extraction and single-particle inductively coupled plasma mass spectrometry were used in combination to quantitatively analyze the naturally generated Ag-NPs and further explore their particle characteristics and stability. The results showed that a conversion behavior of Ag+ to Ag-NPs existed in environmental soil, and the particle sizes of the Ag-NPs were mainly distributed in the 30–40 nm range. It was found that oxygen, illumination, and humic acid could promote the natural generation of Ag-NPs but had different effects on the stability of Ag-NPs. Ag-NPs could be generated and stabilized under the combined action of fulvic acid and humus. This could become a meaningful basis to deeply explore the toxicological effects of Ag-NPs and control Ag-NP pollution from different sources and provide a way to discuss the role and influence of trace metals in geochemical transformations.
研究领域:
环境科学
·
纳米生物学
✓ 已验证
产品关联
DOI
高影响因子
BIORESOURCE TECHNOLOGY
·
2024
·
IF 9.7
Hui-Ying Xu,Ruo-Yu Li,Zi-Qiang Yang,Jia-Fan Qiu,Yu-Bin Su,Carol Sze Ki Lin,Wei-Dong Yang,Hong-Ye Li,Jian-Wei Zheng,Xiang Wang
In this study, the biochemical response of Phaeodactylum tricornutum to varying concentrations of inorganic selenium (Se) was investigated. It was observed that, when combined with fulvic acid, P. tricornutum exhibited enhanced uptake and biotransformation of inorganic Se, as well as increased microalgal lipid biosynthesis. Notably, when subjected to moderate (5 and 10 mg/L) and high (20 and 40 mg/L) concentrations of selenite under fulvic acid treatment, there was a discernible redirection of carbon flux towards lipogenesis and protein biosynthesis from carbohydrates. In addition, the key parameters of microalgae-based biofuels aligned with the necessary criteria outlined in biofuel regulations. Furthermore, the Se removal capabilities of P. tricornutum , assisted by fulvic acid, were coupled with the accumulation of substantial amounts of organic Se, specifically SeCys. These findings present a viable and successful approach to establish a microalgae-based system for Se uptake and biotransformation.
研究领域:
海洋生物学
·
环境科学
·
生物化学
·
生物技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2024
·
IF 7.4
Miao Liu,Xu Chen,Lixiong Cai,Hanbin Luo
To further apply microbially induced carbonate precipitation (MICP) in the environmental civil engineering, this study explored how the widely present humic substances (HS), typically humic acid (HA) and fulvic acid (FA), tailor the strength and microstructures of the MICP-based bio-cement. The presence of HA was found to reduce the yield of bio-precipitates, lower the strength of the resulting cemented sandstone by 27 %, and reduce the particle sizes and surface smoothness of the precipitates. By further examining the biomineralization in the solution system, a similar inhibitory effect on MICP was confirmed and found to be 50 % more substantial when tailored by FA (which possesses more densely distributed functional groups) than HA. Furthermore, HS was found to reduce the crystal sizes by chelating with calcium ions and serving as nucleation sites, and prolonged the existence of the unstable bacteriogenic vaterite by serving as a crystal stabilizer.
研究领域:
环境工程
·
微生物学
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2016
·
IF 4.836
Wen-Yuan Yan,Qi Zhou,Xing Chen,Yong Yang,Yong Zhang,Xing-Jiu Huang,Yu-Cheng Wu
Photocatalytic degradation is one of the most promising methods for removal of fulvic acids (FA), which is a typical category of natural organic contamination in groundwater. In this paper, TiO 2 /graphene nanocomposites (N-RGO/TiO 2 ) were prepared via simple chemical functionalization and one-step hydrothermal method for efficient photodegradation of FA under illumination of a xenon lamp as light source. Here, p -phenylenediamine was used as not only the linkage chemical agent between TiO 2 nanocrystals and graphene, but also the nitrogen dopant for TiO 2 nanocrystals and graphene. During the hydrothermal process, facets of TiO 2 nanocrystals were modulated with addition of HF, and sizes of TiO 2 nanocrystals were controlled by the contents of graphene oxide functionalized with p -phenylenediamine (RGO-NH 2 ). The obtained N-RGO/TiO 2 nanocomposites exhibited a much higher photocatalytic activity and stability for degradation of methyl blue (MB) and FA compared with other TiO 2 samples under xenon lamp irradiation. For the third cycle, the 10wt%N-RGO/TiO 2 catalyst maintains high photoactivity (87%) for the degradation of FA, which is much better than the TiO 2 -N/F (61%) in 3 h. This approach supplies a new strategy to design and synthesize metal oxide and graphene oxide nanocomposites with highly efficient photocatalytic performance.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Bin Zhao,Lixuan Xu,Peixin Shen,Liang Wang,Yiran Qian,Xiaojia He,Xiuru Chu,Pengda Zhang
Transparent exopolymer particle (TEP) formation and its membrane fouling behavior have already been discussed in the presence of various cations. However, the effect of coexisting dissolved organic matters, such as ubiquitous humic substances, is still unknown. In this study, fulvic acid (FA) is used as the surrogate for dissolved humic substances. Its effects on the formation of TEPs derived from different alginate block fractions, namely, heteropolymeric blocks of β - d -mannuronic acids and α - l -guluronic acids (MG-blocks), homopolymeric blocks of α - l -guluronic acids (GG-blocks), and homopolymeric blocks of β - d -mannuronic acids (MM-blocks), and the resulting membrane fouling are investigated. The results showed that the presence of FA enhanced the interaction between alginate blocks and promoted the formation of TEPs. Alginate-associated membrane fouling was also aggravated in the presence of FA, which was positively correlated with the TEP concentration. Moreover, more severe irreversible fouling was detected after backwashing because FA strengthened the adhesive affinity between the membrane and TEPs. The GG-block was the most susceptible to the presence of FA. However, the differences between the three types of alginate block fractions were not significant as the FA concentration increased to 30 mg/L. This study provides insights into the TEP formation from alginate in the presence of FA, and helps to better understand the TEP-associated membrane fouling in complex solution conditions.
研究领域:
环境科学
·
水处理工程
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2015
·Vol. 23
·期 1
·351-365
·
IF 2.828
Wang Changhui,Jiang He-Long,Xu Huacheng,Yin Hongbin
The use of phosphorus (P) inactivating agents to reduce internal P loading from sediment for lake restoration has attracted increasing attention. Reasonably, the physicochemical properties of P inactivating agents may vary with the interference of various environmental factors, leading to the change of control effectiveness and risks. In this study, the effect of fulvic acid (FA) adsorption on the properties of two agents, drinking water treatment residuals (DWTRs) and Phoslock®, was investigated. The results showed that after adsorption, there was little change for the main structures of DWTRs and Phoslock®, but the thermostability of Phoslock®, as well as the particle size and settleability of the two agents decreased. The specific surface area and pore volume of DWTRs also decreased, while those of Phoslock® increased. Further analysis indicated that aluminum and iron in DWTRs were stable during FA adsorption, but a substantial increase of lanthanum release from Phoslock® was observed, in particular at first ( P < 0.01). Moreover, the P immobilization capability of DWTRs had little change after FA adsorption, while the capability of Phoslock® after FA adsorption decreased in solutions ( P < 0.001) and sediments ( P < 0.1); interestingly, from the view of engineering application, the performance of Phoslock® was not substantially affected. Overall, each P inactivating agent had its own particular responses of the physicochemical properties to environment factors, and detailed investigations on the applicability of each agent were essential before practical application.
研究领域:
环境科学
·
湖泊修复
·
水处理技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
International Journal of Environmental Science and Technology
·
2018
·Vol. 16
·期 11
·7275-7284
·
IF 2.037
He Huijun,Wu Bin,Yang Chunping
The colloidal stability and photocatalysis of nano-TiO 2 particles were investigated in the presence of fulvic acids (FA) and electrolytes (NaNO 3 , Na 2 SO 4 , Na 3 PO 4 ) at different pH. Results showed that increasing FA concentration, the absolute value of zeta potential of nano-TiO 2 increased and particle size decreased at all pH which promoted the colloidal stability of nano-TiO 2 . Particle size of nano-TiO 2 was larger with the coexistence of FA and electrolytes than with FA only as the concentration of electrolytes was greater than or equal to 0.01 mol/L. The largest particle size occurred in the presence of Na 3 PO 4 , followed by Na 2 SO 4 and NaNO 3 . Particle size of nano-TiO 2 decreased with higher pH and stability further increased in the presence of FA and/or electrolytes. Nano-TiO 2 stabilization was enhanced by increasing FA concentration when the solution pH was 7.0. However, the removal efficiency of atrazine by nano-TiO 2 decreased with the increase in FA concentration. Adding electrolytes (0.01 mol/L), atrazine removal by nano-TiO 2 further decreased, albeit slightly. The inhibitory effect of electrolytes on nano-TiO 2 removal of atrazine was highest for Na 3 PO 4 , followed by Na 2 SO 4 , and NaNO 3 , which were consistent with the results of colloidal stability of nano-TiO 2 . These findings help to better understand the mechanisms and correlation between colloidal stability and photocatalysis of nano-TiO 2 in the presence of FA and electrolytes.
研究领域:
环境科学
·
化学工程
·
水处理
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2022
·
IF 9.965
Ziyi Cheng,Jing Yang,Lei Li,Yucheng Chen,Xingrun Wang
Currently, simultaneous removal of anionic and cationic pollutants from combined pollution wastewater is a challenging subject. Here, a novel composite adsorbent which can simultaneously adsorb anionic azo dye and heavy metal cations was developed by flocculation inspired assembly of Mg 2 Al layered double hydroxides (LDH) and fulvic acid (FA). The results show that the negatively charged macromolecule FA is firmly intertwined with the positively charged LDH through electrostatic attraction and adsorption bridging. This composite adsorbent (Mg 2 Al LDH-FA) can effectively capture anionic Orange II by anion exchange adsorption derived from LDH component with the maximum adsorption capacity of 604 mg/g. Mg 2 Al LDH-FA also exhibits good adsorption performance for heavy metals due to the complexation with FA and surface precipitation on LDH. The adsorption isotherms of heavy metals coincided with Langmuir model or Freundlich model, and the adsorption capacities for Pb 2+ , Cu 2+ , Ni 2+ , Cd 2+ could reach up to 661.5 mg/g, 116.3 mg/g, 117.3 mg/g, 235.2 mg/g respectively. Particularly, Mg 2 Al LDH-FA can simultaneously uptake Orange II and heavy metals from the stimulated combined pollution wastewater, moreover it shows higher adsorption capacity for each pollutant than that in the single pollutant case as the result of the synergistic adsorption effect between LDH and FA.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Reza Hafezi Moghaddam,Shayessteh Dadfarnia,Ali Mohammad Haji Shabani,Seyed Pezhman Shirmardi
A humic acid-gelatin (HA-Gel) hydrogel, a gallic acid-xanthan gum (GA-XG) hydrogel, a HA-Gel/GA-XG hydrogel, and superabsorbent polymer (SAP) of HA-Gel/GA-XG/polyacrylamide (PAM) hydrogel were synthesized using electron beam irradiation method. The capability of synthesized hydrogels in loading and controlled release of fulvic acid (FA) was studied. The chemical and physical structure of sorbents was confirmed by various analyses. The effect of irradiation dose on mechanical properties, gel percentage, swelling, and absorbency under load (AUL) of the sorbents was investigated. By changing the hydrogel structures into the SAP form, its swelling capacity was increased from 37 to 320 g/g. Both hybrid hydrogel and SAP were reusable for up to 7 cycles. The maximum fertilizer loading capacities for SAP and hybrid hydrogel were 402.1 and, 175.5 mg g −1 , respectively. In comparison to hydrogels, the SAP showed a slower FA-release performance. Thus, in soil media, 86 % of FA was released in 15–20 days from the hybrid hydrogel while with the SAP, 81 % of FA was released in 30–35 days. The significant improvement in the growth of fodder corn treated with FA-loaded SAP in the greenhouse media in comparison to the control groups showed the effective performance of the designed SAP, favoring its practical applications.
研究领域:
材料科学
·
农业科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）