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The East Zhejiang Canal is an artificial waterway located in the plains of East China. Because of its role in providing social services, it is frequently subjected to human activities affecting its health. To improve the water resource management and condition of this canal, assessment of its ecological health is necessary. We measured water quality variables and benthic diatom and macroinvertebrate assemblages to evaluate the ecological status of the canal. We found that the canal was eutrophic with an average chemical trophic level index of 64.3 and an average trophic diatom index of 68.1 (with Nitzschia palea, Melosira varians, and Navicula rostellata, Encyonema minutum abundant). Macroinvertebrate assemblages also showed that the canal was eutrophic based on the dominance of Limnodrilus sp. A low BMWP (Biological Monitoring Working Party) score further indicated the poor water quality of the canal. Correlation analysis indicated that phosphorus was the main driver of eutrophication in the canal. Consequently, more attention should be paid to reduce phosphorus loadings. [ABSTRACT FROM AUTHOR]

Heavy metals posed a very important treat to public health and environment because of their toxicity, bioaccumulation and biodegradability properties. The development of high efficiency, low cost and good chemical stability adsorbents for removing heavy metals from aqueous solution was very urgent. The removal capacity of Cr(VI) by the preparation of porous biochar decorated with MnFe2O4 magnetic nanoparticle (MnFe2O4@PS) was evaluated. Results showed that the operational parameters had an important influence on Cr(VI) removal. Pseudo-second-order model and Langmuir model could be used to describe the adsorption process. The adsorption process of Cr(VI) by MnFe2O4@PS composites was a spontaneous, endothermic and randomness process. The removal capacity of Cr(VI) by MnFe2O4@PS composites reached 46.51 mg/g. The main mechanisms contained electrostatic interaction, Surface adsorption, surface complexation and chemical precipitation. MnFe2O4@PS composites exhibited high removal capacity of Cr(VI), good chemical stability and recyclability. [ABSTRACT FROM AUTHOR]

Large amounts of nitrogen and phosphorus elements were discharged into the environment. They would lead to severe eutrophication of water bodies. The development of economically efficient, green and ecological adsorbents is the current focus for adsorption technology. In this research, the cost-effective biochar modified by Mg/Ca bimetallic oxide composites (Mg/Ca@PS) for adsorption of NO3- and PO43- ions in aqueous solution was investigated. Additionally, Mg/Ca@PS also was characterized by scanning electron microscopy, transmission electron microscopy, energydispersive X-ray analysis, X-ray diffraction, and Fourier-transform infrared spectroscopy, respectively. The experimental results showed that the adsorption process of NO3- ions in aqueous solution by Mg/Ca@PS could be described by pseudo-second-order kinetic model and Langmuir isotherm model, respectively. However, the adsorption process of PO43- ions in solution by Mg/Ca@PS could be described by pseudo-second-order kinetic model and Freundlich isotherm model, respectively. Additionally, the adsorption capacity of NO3- and PO43- ions in aqueous solution by Mg/Ca@PS were 18.52 and 47.85 mg/g, respectively. The adsorption mechanisms of NO3- ionsand PO43- ions in solution by Mg/Ca@PS mainly contain surface adsorption, intraparticle diffusion, electrostatic attraction, and ion exchange. Moreover, the adsorption mechanism of PO43- ions in solution by Mg/Ca@PS also includes chemical precipitation. In the five recycle times, the removal rate of NO3- and PO43- ions still reached 55.31% and 48.12%, respectively. It indicated that the chemical stability of Mg/Ca@PS was very well, and it was a good environmental friendly material. [ABSTRACT FROM AUTHOR]

The dye wastewater was considered as a kind of harmful environmental pollutant. It would destroy the ecological environment, and formed carcinogens affecting human health. Therefore, it was very urgent to treat dye wastewater efficiently. In this work, the novel Mg-Fe bimetallic oxide@biochar composites (Mg-Fe@BC) were prepared from peanut shell by the chemical method of microwave-assisted hydrothermal. The adsorption of Disperse Red 167 dye (DR 167 dye) by Mg-Fe@BC was carried out in a serial of adsorption experiments. The characterization of Mg-Fe@ BC was characterized by Fourier-transform infrared spectroscopy, X-ray diffraction, transmission electron microscopy and scanning electron microscopy-energy-dispersive X-ray spectroscopy. The results showed that biochar was successfully loaded by the Mg-Fe bimetallic oxide nanoparticles. The adsorption capacity of DR 167 dye by Mg-Fe@BC was higher than that of the unmodified biochar. The removal rate of DR 167 dye by Mg-Fe@BC could reach 92.7%. The functional groups (such as O-H, C=C or C-C, COO- and C-O-C) could be observed on the surface of Mg-Fe@ BC. The adsorption kinetics of DR 167 dye by Mg-Fe@BC was fitted with pseudo-second-order kinetic and Langmuir models. The proposed mechanisms of DR 167 dye removal by Mg-Fe@BC involved surface complexation, p-p interaction, hydrogen bond and electrostatic attraction. [ABSTRACT FROM AUTHOR]

The Hedgehog (Hh) signaling pathway is correlated with hepatic stellate cells (HSCs) activation and liver fibrosis. Gli2 is a key transcription effector of Hh signaling. However, the role of Gli2 in HSC-mediated liver fibrosis progression is largely unknown. In the present study, we investigated the effect of Gli2 on liver fibrogenesis and its possible mechanism using conditional knockout (cKO) Gli2 mice and HSC models. Wild-type (WT) and GFAP-CreERT;Gli2flox/flox male mice were exposed to CCl4 for 1 mo to induce liver fibrosis. Primary HSCs were isolated from mice and the transition of HSCs into a myofibroblastic phenotype was evaluated. Livers from mice underwent histological, immunohistochemical, and immunofluorescence analyses. The expression levels of proteins and genes were evaluated by Western blot (WB) analysis and quantitative real-time polymerase chain reaction (qRT-PCR), respectively. RNA-seq was used to screen differentially expressed genes. Results showed that CCl4 treatment induced liver fibrosis, promoted HSCs activation and proliferation, and upregulated Hh signaling activity. The cKO of Gli2 in GFAP-CreERT;Gli2flox/flox mice decreased liver fibrosis as well as HSC activation and proliferation. In vitro studies showed that KO of Gli2 in HSCs blocked cell proliferation and activation by decrease of cyclin D1/D2 expression. The RNA-seq results revealed that the expression levels TGF-b 1 ligands were downregulated in Gli2 KO HSCs. Furthermore, overexpression of Gli2 rescued proliferation and activation of HSCs by upregulation of TGF-b signaling activity. Our data demonstrated that Gli2 regulated HSC activation and liver fibrosis by TGF-b signaling, thus providing support for future Gli2-based investigations of liver fibrosis therapy. [ABSTRACT FROM AUTHOR]

A novel biochar-montmorillonite (B@M) composites was synthesized by heating peanut shell B@M and was used to remove Cr(VI) from acid mine drainage (AMD). Batch characterization confirmed that the biochar surface was covered with montmorillonite successfully. The batch adsorption experiment demonstrated that the maximum adsorption capacity of biochar and B@M was 9.18 and 12.18 mg/g, respectively. The adsorption kinetics and isotherms can be satisfactorily fitted by pseudo-second kinetic model and Langmuir model, respectively. No effect of SO42- on Cr(VI) removal implied that B@M can simultaneously remove Cr(VI) from SO42- aqueous solutions. XPS analysis showed that adsorption, reduction and precipitation were involved in the removal process due to the presence of Fe(II) in montmorillonite. These findings suggested that the engineered biochar-based composite may be a valuable adsorbent for the removal of Cr(VI) from AMD. [ABSTRACT FROM AUTHOR]

Carbon nanofibers (CNFs) have been extensively investigated due to their strong uptake and complexation ability. In this work, CNFs was characterized by using SEM, TEM, FTIR, XPS and Raman spectra. The uptake of Co(II) and Ni(II) on bacterium-derived CNFs as a function of contact time, pH, ionic strength and temperature was investigated using batch techniques. The pH-dependent uptake indicated that the uptake of Co(II) and Ni(II) onto CNFs was significantly higher at high pH values than that at low pH values. The uptake of Co(II) and Ni(II) onto CNFs was hardly affected by ionic strength, suggesting the formation of inner-sphere surface complexation of Co(II) and Ni(II) onto CNFs over a wide pH range. The Langmuir model described the uptake of Co(II) and Ni(II) onto CNFs better than the other models did. According to regeneration experiments, CNFs displayed good recoverability and recyclability in the Co(II) and Ni(II) uptake process. The findings presented herein play a significant role in the scavenging of metal ions on inexpensive and available CNFs in environmental cleanup applications. [ABSTRACT FROM AUTHOR]

Herein, the sorption of Co(II) onto rice straw-derived biochar as a function of various environmental conditions was investigated in batch experiments. The removal efficiency was strongly affected by pH but not by ionic strength over the whole pH range. At low pH values, inner-sphere surface complexation dominated the sorption. While at high pH values, both precipitation and inner-sphere surface complexation controlled sorption process. The kinetics was simulated well by the pseudo-second- order model and was affected by both the film diffusion and the intraparticle diffusion model. The initial Co(II) concentration significantly enhanced the sorption amount of Co(II) on biochar, but weakly affected the sorption rate. Any of the Langmuir, Freundlich, and Dubinin–Radushkevich isotherm models could simulate sorption isotherms well, while the Langmuir model fitted it the best. The thermodynamic data implied the Co(II) sorption was enhanced at high temperature and was a spontaneous and endothermic process. In addition, the biochar can be employed repeatedly in Co(II) sorption process. These results demonstrate that rice straw-derived biochar can be a suitable adsorbent for Co(II) removal from aqueous solutions. [ABSTRACT FROM AUTHOR]

Biochar, as a cost-efficient adsorbent, is of major interest in the removal of heavy metals from wastewater. Herein, batch experiments were conducted to investigate the performance of biochar derived from rice straw for the removal of Ni(II) as a function of various environmental conditions. The results showed that Ni(II) sorption was strongly dependent on pH but independent of ionic strength and the effects of electrolyte ions could be negligible over the whole pH range. Ionic exchange and inner-sphere surface complexation dominated the sorption of Ni(II). Humic/fulvic acids clearly enhanced the Ni(II) sorption at pH <7.2 but inhibited the sorption at pH >7.2. The sorption reached equilibrium within 10 hours, and the kinetics followed a pseudo-second-order rate model. Any of the Langmuir, Freundlich, or Dubinin-Radushkevich isotherm models could describe the sorption well, but the Langmuir model described it best. The maximum sorption capacity calculated from the Langmuir model was 0.257 m⋅mol/g. The thermodynamic parameters suggested that Ni(II) sorption was a spontaneous and endothermic process and was enhanced at high temperature. The results of this work indicate that biochar derived from rice straw may be a valuable bio-sorbent for Ni(II) in aqueous solutions, but it still requires further modification. [ABSTRACT FROM AUTHOR]

In this paper, the use of graphene oxide (GO), high efficiency and low-risk adsorbent, has been studied for the removal of UO22+ from aqueous solutions. A series of experiments was conducted in a batch system to assess the effect of the system variables, i.e. contact time, initial pH, ionic strength, temperature, solid concentration and humic substances. The results indicated that the uptake is strongly dependent on pH but independent of ionic strength. A stimulative effect of HA/FA on UO22+ uptake was found at pH < 7.0, whereas inhibitory effect was observed at pH > 7.0. The adsorption kinetics of UO22+ uptake on GO was found to follow pseudo-second-order rate kinetic model very well, with a good correlation (R² > 0.99), indicating that the chemical adsorption was the rate-limiting step. The Linear, Langmuir, Freundlich, and Dubinin-Redushkevich (D-R) isotherms were used to analyze the equilibrium data at different temperatures, and the Langmuir isotherm model fits the sorption isotherms significantly better than the other three models. The maximum uptake capacity (qmax) reached 2.3532 × 10-4 mol·g-1 at 338 K, it is estimated by Langmuir. The thermodynamic analysis derived from temperature dependent uptake isotherms suggests that the uptake process of UO22+ on GO is spontaneous and endothermic. Results also showed that the GO was favourable adsorbent for UO22+. [ABSTRACT FROM AUTHOR]

In the present study, carboxymethyl-β-cyclodextrin (CM-CD) molecules were introduced onto the surfaces of Fe3O4 nanoparticles via chemical co-precipitation approach. The synthesized Fe3O4 /CM-CD composite exhibited high magnetism and could be easily separated from the aqueous phase by exposing to an external magnetic field. In addition, the composite was stable in solution over a wide pH range. The effects of contact time, solution pH, ionic strength, solid dosage and temperature on the removal performance of Fe3O4 /CM-CD toward a cationic dye named C.I. Basic Blue 3 (BB3) were evaluated by using the batch technique. The sorption kinetic process achieved equilibrium within a contact time of 90 min. The sorption isotherm data were simulated by the Langmuir model well and the maximum sorption capacity was calculated to be 203.54 mg/g at 298 K. The Fe3O4 /CM-CD composite exhibited favorable removal performance toward BB3 in both the single-solute system and the simulation effluent. After sorption equilibrium, the BB3-loaded composite could be easily regenerated and reused for multiple sorption/desorption cycles. The experimental findings herein proposed the feasibility of adopting Fe3O4/CM-CD composite for the decontamination of BB3 from the polluted water systems. [ABSTRACT FROM AUTHOR]

In this work, sorption of Ni(II) from aqueous solution to goethite as a function of various water quality parameters and temperature was investigated. The results indicated that the pseudo-second-order rate equation fitted the kinetic sorption well. The sorption of Ni(II) to goethite was strongly dependent on pH and ionic strength. A positive effect of HA/FA on Ni(II) sorption was found at pH < 8.0, whereas a negative effect was observed at pH > 8.0. The Langmuir, Freundlich, and D-R models were applied to simulate the sorption isotherms at three different temperatures of 293.15 K, 313.15 K and 333.15 K. The thermodynamic parameters (Δ H0, Δ S0 and Δ G0) were calculated from the temperature dependent sorption, and the results indicated that the sorption was endothermic and spontaneous. At low pH, the sorption of Ni(II) was dominated by outer-sphere surface complexation or ion exchange with Na+/H+ on goethite surfaces, whereas inner-sphere surface complexation was the main sorption mechanism at high pH. [ABSTRACT FROM AUTHOR]

The novel carbon based acid has been synthesized via one-step hydrothermal carbonization of furaldehyde and hydroxyethylsulfonic acid. A highly efficient procedure for the synthesis of fructone has been developed using the novel carbon based acid. The results showed that the catalyst possessed high activity for the reaction, giving a yield of over 95%. The advantages of high activity, stability, reusability and low cost for a simple synthesis procedure and wide applicability to various diols and β-keto esters make this novel carbon based acid one of the best choices for the reaction. [ABSTRACT FROM AUTHOR]