ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
·
2014
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IF 2.482
Xinghao Wang,Ruijuan Qu,Zhongbo Wei,Xi Yang,Zunyao Wang
Mercury (Hg) compounds are widely distributed toxic environmental and industrial pollutants and they may bring danger to growth and development of aquatic organisms. The distribution of Hg species in the 3 percent NaCl solution was calculated using the chemical equilibrium model Visual MINTEQ, which demonstrated that Hg was mainly complexed by chlorides in the pH range 5.0–9.0 and the proportions of HgCl 4 2− , HgCl 3 − and HgCl 2 (aq) reached to 95 percent of total Hg. Then the effects of cations (Ca 2+ , Mg 2+ , K + and H + ), anions (HCO 3 − , NO 3 − , SO 4 2− and HPO 4 2− ) and complexing agents (ethylene diamine tetraacetic acid (EDTA) and dissolved organic matter (DOM)) on Hg toxicity to Photobacterium phosphoreum were evaluated in standardized 15 min acute toxicity tests . The significant increase of 6.3-fold in EC 50 data with increasing pH was observed over the tested pH range of 5.0–8.0, which suggested the possible competition between hydroxyl and the negatively charged chloro-complex. By contrast, it was found that major cations (Ca 2+ , Mg 2+ and K + ) have little effect on Hg toxicity to P. phosphoreum . An interesting finding was that the addition of HPO 4 2− significantly increased Hg toxicity, which may imply that the addition of phosphate increased the soluble Hg–chloro complex species. Additions of complexing agents (EDTA and DOM) into the exposure water increased Hg bioavailability via complexation of Hg. Finally, a model which incorporated the effect of pH, HPO 4 2− , HCO 3 − , SO 4 2− and DOM on Hg toxicity was developed to predict acute Hg toxicity for P. phosphoreum , which may be a useful tool in setting realistic water quality criteria for different types of water.
研究领域:
环境生物学
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毒理学
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DOI
PubMed
高影响因子
CHEMOSPHERE
·
2024
·
IF 8.1
Jian Liu,Xueren Huang,Zhengji Yi
Complexing agents (CAs) can be used for the removal of Cr(VI) via nanoscale Fe 0 (nZVI) reduction in cost-effective manner. However, nZVI is prone to aggregation and passivation, and some conventional CAs are toxic and difficult to biodegrade, potentially causing secondary pollution. Therefore, selecting an environmentally friendly CA for assisting in the removal of Cr(VI) via supported nZVI is imperative. Herein, NaA molecular sieve membrane-supported nZVI (nZVI/NaA-NF) was prepared via the secondary growth and liquid-phase reduction method using nickel foam (NF) as the carrier. The physicochemical characteristics of nZVI/NaA-NF before and after reaction were analysed via SEM, EDS, and XPS. A CA-improved nZVI/NaA-NF was used for the effective removal of Cr(VI) in a continuous fixed-bed system. Furthermore, the influences of various experimental factors including the CA type, CA concentration, solution pH, space velocity, and inlet Cr(VI) concentration on Cr(VI) removal were systematically investigated. The results demonstrated that nZVI particles were homogeneously immobilized on the NaA molecular sieve membrane/NF for fresh nZVI/NaA-NF, and tetrasodium iminidisuccinate (IDS-4Na) inhibited the aggregation of Cr(III)/Fe(III) (hydr)oxide precipitates during the reaction. IDS-4Na demonstrated excellent promotive effect on Cr(VI) removal via nZVI/NaA-NF. The breakthrough time for Cr(VI) in the addition of IDS-4Na was considerably longer than that of nZVI/NaA-NF alone. The breakthrough concentration of Cr(VI) only reached 1.1% and 9.9% of the inlet concentration at 220 and 240 min, with an IDS-4Na concentration of 4 mM, a pH of 2.5, and a space velocity of 0.265 min −1 . The Bohart–Adams model was appropriate to predict the initial part of Cr(VI) breakthrough curves in the nZVI/NaA-NF fixed bed. The saturated concentration ( N 0 ) increased with an increase in inlet Cr(VI) concentration. The Yoon–Nelson model afforded good fitting results for all breakthrough curves of Cr(VI). The k′ value increased with an increase in space velocity, and the τ value decreased.
研究领域:
环境科学
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材料科学
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DOI
PubMed
高影响因子
BIOTECHNOLOGY PROGRESS
·
2019
·Vol. 36
·期 2
·e2930
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IF 2.406
Hangyan Ji,Yu Wang,Yuxiang Bai,Xiaoxiao Li,Lizhong Qiu,Zhengyu Jin
The production of γ-cyclodextrin usually includes the utilization of organic complexants. However, the non-complexant production of γ-cyclodextrin is always being explored due to the defects of organic complexants. However, in non-complexant production, the separation of γ-cyclodextrin from α- and β-cyclodextrin is still a challenge. Here, the selective hydrolysis ability of a cyclodextrinase designated PpCD (cyclodextrinase from Palaeococcus pacificus ) on α-cyclodextrin, β-cyclodextrin, and γ-cyclodextrin was proved. The k cat /K m values of PpCD for α-cyclodextrin and β-cyclodextrin were roughly 12-fold and 5-fold higher than that of γ-cyclodextrin. It was proved that PpCD had selective hydrolysis ability and its γ-cyclodextrin purification performance was apparent on various simulated cyclodextrin mixtures with reported proportions derived from different CGTases. Besides, the hydrolysis temperature was optimized and it could be seen that 85°C was appropriate for the production of γ-cyclodextrin. In addition, the production of γ-cyclodextrin was achieved by using PpCD in the γ-CGTase reaction products.
研究领域:
生物化学
·
酶工程
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DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Hao Peng,Jing Guo,Guixuan Jin,Jingjing Wang,Qiuyan Wu,Hongwei Liu,Aiyang Li
This study investigated the effectiveness of tartaric acid (TA) for the direct reduction of pentavalent vanadium (V(V)), a critical process in vanadium-related industries. Leveraging TA's carboxyl groups, which showed promise as reducing agents for V(V), the research systematically evaluated the effects of key parameters including reaction temperature, reaction time, H 2 SO 4 concentration, and TA dosage on reduction efficiency. Response surface methodology (RSM) analyzed parameter significance and interactions, while density functional theory (DFT) elucidated the molecular reduction mechanism. The process was further validated using an industrially sourced vanadium-rich solution. Results demonstrated that TA effectively reduces V(V) under elevated temperatures and TA dosage, achieving 100% within a short time under optimized conditions. RSM revealed all parameters positively influenced the reduction process, ranked by significance as: reaction temperature > reaction time > H 2 SO 4 concentration > TA dosage, underscoring the dominance of thermal activation. DFT analysis identified the molecular mechanism: the carbon atom within TA's carboxyl group (-COOH) donated lone pair electrons to V(V), facilitating reduction to V(IV). Successful application to the industrial vanadium solution confirmed TA's effectiveness. This study established TA as an efficient V(V) reducing agent, clarified its electron-transfer mechanism, and confirmed its dual role as both reductant and complexing agent.
研究领域:
无机化学
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环境科学
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工业化学
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冶金学
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绿色化学
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DOI
高影响因子
MEDIATORS OF INFLAMMATION
·
2024
·
IF 4.4
Shuyu Ge,Zhenghong Guo,Ting Xiao,Pingping Sun,Bo Yang,Yin Ying
As an interstitial fibrosis disease characterized by diffuse alveolitis and structural alveolar disorders, idiopathic pulmonary fibrosis (IPF) has high lethality but lacks limited therapeutic drugs. A hospital preparation used for the treatment of viral pneumonia, Qingfei Tongluo mixture (QFTL), is rumored to have protective effects against inflammatory and respiratory disease. This study aims to confirm whether it has a therapeutic effect on bleomycin-induced IPF in rats and to elucidate its mechanism of action. Male SD rats were randomly divided into the following groups: control, model, CQ + QFTL (84 mg/kg chloroquine (CQ) + 3.64 g/kg QFTL), QFTL-L, M, H (3.64, 7.28, and 14.56 g/kg, respectively) and pirfenidone (PFD 420 mg/kg). After induction modeling and drug intervention, blood samples and lung tissue were collected for further detection. Body weight and lung coefficient were examined, combined with hematoxylin and eosin (H&E) and Masson staining to observe lung tissue lesions. The enzyme-linked immunosorbent assay (ELISA) and the hydroxyproline (HYP) assay kit were used to detect changes in proinflammatory factors (transforming growth factor-β (TGF-β), tumor necrosis factor-α (TNF-α), and interleukin-1β (IL-1β)) and HYP. Immunohistochemistry and Western blotting were performed to observe changes in proteins related to pulmonary fibrosis (α-smooth muscle actin (α-SMA) and matrix metalloproteinase 12 (MMP12)) and autophagy (P62 and mechanistic target of rapamycin (mTOR)). Treatment with QFTL significantly improved the adverse effects of bleomycin on body weight, lung coefficient, and pathological changes. Then, QFTL reduced bleomycin-induced increases in proinflammatory mediators and HYP. The expression changes of pulmonary fibrosis and autophagy marker proteins are attenuated by QFTL. Furthermore, the autophagy inhibitor CQ significantly reversed the downward trend in HYP levels and α-SMA protein expression, which QFTL improved in BLM-induced pulmonary fibrosis rats. In conclusion, QFTL could effectively attenuate bleomycin-induced inflammation and pulmonary fibrosis through mTOR-dependent autophagy in rats. Therefore, QFTL has the potential to be an alternative treatment for IPF in clinical practice.
研究领域:
药理学
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肺病学
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免疫学
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DOI
PubMed
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
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2022
·
IF 4.598
Shuang Wu,Zheni Wang,Lei Wan,Chenghui Luo,Shams Ali Baig,Xinhua Xu
In the present study, Pd/Ni foam electrode was prepared by improved impregnation method for electrocatalytic hydrodechlorination (ECH) of clofibric acid (CA). The effects of complexing agent addition into the impregnation solution for the formation of Ni(OH) 2 and the ECH activity of Pd/Ni foam electrode were investigated. Results revealed that the introduction of sodium acetate (the complexing agent) greatly enhanced the ECH activity as compared to common impregnation liquid. Characterizations analyses demonstrated that the addition of sodium acetate did not change the phase of the electrode’s surface, but effectively reduced the deposition of Ni(OH) 2 . The surface morphology of the electrode was changed simultaneously by the addition of sodium acetate and the interlacing structure of Ni(OH) 2 and Pd catalyst was formed. NaAc before -Pd/Ni and NaAc after -Pd/Ni foam electrodes were used to perform ECH experiments on CA, and the combined Pd/Ni foam 15 min electrode was compared with the Pd/Ni foam 6 h electrode. After 2 h of electrolysis, the NaAc after -Pd/Ni foam electrode was found to remove the CA (∼100%) in the solution, which was 1.3 times the removal rate of the Pd/Ni foam 6 h electrode to CA and exceeded the Pd/Ni foam 15 min electrode. Findings from the present study demonstrated that adding the complexing agent into the impregnation solution can improve the ECH activity of Pd/Ni foam electrode and achieve a faster and more efficient dechlorination effect of CA.
研究领域:
环境化学
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电化学
·
催化
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2025
·
IF 7.2
Qin Wang,Xiaoyun Li,Huanting Li,Lijun Liu,Xu Zhang,Yanfang Li,Maoqing Kang,Qifeng Li,Junwei Wang
CO 2 -based poly(ether-carbonate) polyols (CO 2 -based PEC polyols), composed of carbonate and ether linkages, were synthesized by the copolymerization of CO 2 , chain transfer agent and propylene oxide (PO) in the presence of Zn–Co double metal cyanide (DMC) complex catalyst, and employed to prepare polyurethane elastomers (PUEs) successfully. To obtain high-quality poly(ether–carbonate) polyols, DMC catalysts were further modified by versatile low-molecule compounds and polymers including maleic acid, D-gluconate acid, ethylenediaminetetraacetic acid, polyacrylic acid, and polyacrylamide (PAM) as co-complexing agents (co-CAs). The catalysts bearing polymer co-CAs displayed much superior activity to those of low-molecule co-CAs counterparts. The best copolymerization activity was achieved by the DMC–PAM catalyst with a PO conversion of 86.9 % and a CO 2 incorporation of 23. 9 mol%. It was attributed to the low-symmetry crystal structure, high specific surface area, and strong acidity. Importantly, a conclusion concerning that N-containing polymers were highly effective co-CAs of the DMC catalysts was drawn. EXAFS analysis proved that various co-CAs caused changes in the coordination environment around Zn atoms. In addition, it was confirmed that the carbonate units in CO 2 -based polyols endowed PU−PEC with high tensile and tear strength, and strong water/toluene resistance, while the ether units in CO 2 -based polyols provided the advantages of high elongation at break, low viscosity, and low cost.
研究领域:
材料科学
·
化学工程
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DOI
高影响因子
Nature Communications
·
2025
·
IF 15.7
Yang Jiahui,Wei Wei,Zhou Chengxi,Tan Xinyi,Wu Tai-Sing,Zhang Yi,Soo Yun-Liang,Li Molly Meng-Jung,Robertson Alex W.,Tang Ao,Sun Zhenyu
The development of a safe and affordable redox flow battery technology is important for storing intermittent renewable energy. Here, we design a stable aqueous organic iron-cerium redox flow battery based on the inexpensive metal iron and the abundant rare earth metal cerium, enabled by the universal complexing agent diethylenetriamine pentaacetic acid. Molecular dynamics simulations are employed to screen for carboxyl-containing ligands with different electron donating capacities, revealing that diethylenetriamine pentaacetic acid is an effective candidate to chelate iron and cerium in the negolyte and posolyte, respectively, as verified by experimental characterization. The complexing agent enhances the redox characteristics of iron and cerium and reduces osmotic water migration between the negative and positive chambers by allowing the same ligand in both electrolytes. Our iron-cerium redox flow battery achieves an energy efficiency of 87.7% at 40 mA cm −2 and 80.6% at 100 mA cm −2 , while retaining 95.3% of its initial capacity and maintaining around 86.3% energy efficiency after 500 cycles under neutral environments (100% of state-of-charge). The capacity is still preserved after 1779 cycles even when cycled at high-rates (80 mA·cm −2 , 70% of state-of-charge).
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PubMed
高影响因子
危险品化学品经营许可证（带存储）