ACS Applied Polymer Materials
·
2021
·
IF 4.089
Weiming Ji,Shunni Dong,Wei Fan,Chao Lv,Jingjing Nie,Binyang Du
A functional monomer, namely, 1-hexene-4-(benzal-2,2′:6′,2″-terpyridines)pyridinium bromide (HTP) was synthesized and incorporated into the cross-linking network of microgels. The HTP-functionalized microgels (HTP-MGs) were synthesized by surfactant-free emulsion copolymerization with N-isopropylacrylamide as the main monomer, 1-vinylimidazole as a quaternization cross-linkable comonomer, HTP as the functional comonomer, and 1,6-dibromhexane as the quaternization agent. The obtained HTP-MGs were spherical with a hydrodynamic radius Rh of 205 ± 2 nm and uniform size distribution in HEPES buffer aqueous solutions at 25 °C. The HTP-MGs exhibited a characteristic UV–vis absorption peak at 315 nm and a characteristic fluorescent emission peak at 430 nm, respectively. The HTP-MGs can selectively, sensitively, and optically respond to Fe2+ ions in aqueous solution with a fast response time of 3 s in wide pH (2–10) and temperature (25–50 °C) ranges, resulting in a color change in HTP-MG HEPES buffer aqueous solutions from colorless to purplish red, which can be easily distinguished by naked eyes. A linear concentration range of 0–14 μM and a detection limit (DL) of 82 nM were achieved for detecting Fe2+ ions in HEPES buffer aqueous solutions (pH = 7) at 25 °C. The molar binding ratio of the HTP moiety within HTP-MGs to Fe2+ ions was 2:1, as revealed by Job’s plot. It was found that the coexistence of 15 species of other metal ions except of Cu2+ ions studied here did not affect the detection of Fe2+ ions. Furthermore, a fluorescent emission peak at 371 nm with strongly enhanced fluorescent intensity was observed for HTP-MG HEPES buffer aqueous solutions with the addition of Zn2+ or Cd2+ ions. By combining the optical response to Fe2+ ions and fluorescent response to Zn2+ ions, it was demonstrated that HTP-MGs could also have potential applications in the fields of encryption and anti-counterfeiting.
研究领域:
材料科学
·
分析化学
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL POLLUTION
·
2022
·
IF 9.988
Yao Tang,Jibo Dou,Zhijiang Lu,Jianming Xu,Yan He
The sluggish Fe 3+ /Fe 2+ cycle was the rate-limiting step in the Fenton-like reaction, and metal-free carbonaceous materials are considered as emerging alternatives to solve this problem. However, the effect of carbon material properties on the distribution of reactive species remains poorly understood. This study investigated the possibility and mechanism of using biochar to accelerate the Fe 3+ /Fe 2+ cycle to overcome the low efficiency of Fe 3+ /persulfate (PS) catalytic oxidation of phenanthrene . More importantly, the contribution of reactive species in the reaction systems with the variation of biochar pyrolysis temperatures was quantitatively studied. The results showed that medium-temperature derived biochar (BC500) had the greatest ability to enhance the Fenton-like system compared to the low- and high-temperature (BC350/700), and the first-order rate constant achieved 5.2 and 35.7-fold increase against the biochar/PS and Fe 3+ /PS systems, respectively. Using electrochemical evidence, sulfoxide probe tests, and steady-state concentration calculations, radicals yields were found to rise and then reduce with decreasing pyrolysis temperature, while the nonradical contribution of Fe(IV) increased to 56.3%. Electron paramagnetic resonance, Boehm titration, and Raman spectroscopy unraveled that the enhanced effect of biochar resulted from itself persistent free radicals, phenolic-OH, and edge defects, which enabled electron transfer between Fe 3+ and biochar. Fe 2+ was thus continuously generated and effectively activated the PS. This work enables a better understanding of the Fe 3+ -mediated Fenton-like reaction in the presence of biochar and provides a sustainable green strategy for Fenton chemistry with potential applications.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Nano Materials
·
2021
·
IF 5.097
Yaxin Xu,Peipei Li,Xiaojun Hu,Haoyu Chen,Ying Tang,Yu Zhu,Xiaohua Zhu,Youyu Zhang,Meiling Liu,Shouzhuo Yao
Nanozymes are considered as ideal substitutes for nature enzymes; however, the enzyme activity and the relevant detection sensitivity in actual samples still need to be further improved. Here, a nanomaterial of CuO NP-POM composed of polyoxometalate (POM) decorated with copper oxide nanoparticles (CuO NPs), which possessed tetraenzyme mimetic activities including oxidase (OXD)-, peroxidase (POD)-, catalase (CAT)-, and glutathione peroxidase (GPx)-like activities was developed. The corresponding catalytic performances, mechanisms, and kinetics were systematically investigated. Based on the POD-like activity of a CuO NP-POM nanocomposite, a colorimetric sensing platform for ascorbic acid (AA) was built with the detection limit of 15 nM, depending on the fact that AA can efficiently react with the oxidation product of TMB, which was catalyzed by CuO NP-POM on the basis of the POD-like activity. A simple fluorometric sensor for Fe2+ was developed on the basis of the GPx-like activity of CuO NP-POM with the detection limit of 8.0 nM. CuO NP-POM can weaken the fluorescence of the isoindole derivative derived from GSH and o-phthalaldehyde (OPA) due to the excellent GPx-like activity, which can accelerate the catalysis of GSH into GSSG in the presence of H2O2. However, in the presence of Fe2+, the fluorescence was recovered owing to the fact that the Fenton reaction between Fe2+ and H2O2 could reduce GSSG into GSH. The proposed colorimetric and fluorometric sensors have been successfully applied in detecting AA and Fe2+ in several food and biological samples. This work not only developed a nanocomposite with enhanced multinanozyme activity but also offered rapidly detection methods for the analysis of specific targets via the special nanozyme activities.
研究领域:
生物化学
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材料科学
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分析化学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Haiyu Zhang,Qinbo Cao,Yan Yan,Heng Zou,Xingguo Huang,Dianwen Liu
The flotation separation of galena (PbS) and chalcopyrite (CuFeS 2 ) is not yet fully resolved due to the lack of efficient depressants. This study proposed a new depressant, i.e. an Fe 2+ /NaClO system, as an efficient PbS depressant. The inhibition effect of the Fe 2+ /NaClO system is attributed to the oxidation effect of •OH radicals from the reaction between HClO and Fe 2+ . The recovery of PbS is only 9.48 % and that of CuFeS 2 is 82.33 % under the following conditions: pH 3.5, 4 min reaction time, 10:1 Fe 2+ :NaClO molar ratio and 1 × 10 −2 mol/L NaClO concentration. Contact angle test results suggested that the hydrophobicity of PbS was decreased by conditioning with the Fe 2+ /NaClO system. X-ray photoelectron spectroscopy results showed that the S 2− species on the PbS surface was oxidised into SO 4 2− , and thus, PbSO 4 occurred on the PbS surface. Furthermore, SO 4 2− concentration reached 61.67 % of the total S species. Oxidative production coated the PbS surface well, depressing PbS flotation. However, the Fe 2+ /NaClO system barely changed the components of the CuFeS 2 surface. The CuFeS 2 surface still exhibits a high hydrophobic level. Therefore, PbS can be efficiently separated from CuFeS 2 by using the Fe 2+ /NaClO system.
研究领域:
矿物加工工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
·
2024
·
IF 4.1
Yingzi Lin,Mengshi Wang,Junjie Chen,Siwen Li,Yuanyuan Zhang,Liangliang Wei,Ningning Sun,Chengyu Liu,Junjie Zhao
Based on the deficiency of the Fe 2+ catalyzed persulfate (PDS) process, ultraviolet (UV) synergistic Fe 2+ activated PDS system was introduced in this study for the degradation of acid orange 7 (AO7) dye. The effects of different initial pH, PDS dosage, Fe 2+ dosage, and different UV intensities on the degradation rate of AO7 were investigated, and a kinetic model for the apparent reaction rate was determined. The results showed that the UV/Fe 2+ /PDS system was effective in degrading AO7 in a wide pH range. Under optimal conditions, 96 % removal of AO7 was achieved in 10 min. The effects of different inorganic anions on AO7 were discussed; Cl − had little effect on the degradation effect, and SO 4 2− , NO 3 − and HCO 3 − inhibited the degradation of AO7 by the system to varying degrees. The presence of reactive radicals (SO 4 ·− and·OH) in the reaction was determined by quenching experiments and EPR capture and their degradation contribution was further investigated. Nine intermediates of AO7 were detected by LC-MS/MS, and the degradation pathway of AO7 was inferred by combining with UV-Vis spectra. Finally, the ecotoxicity and tritogenic effects of AO7 intermediates were assessed by Toxtree and T.E.S.T toxicity prediction models, which showed that the final degradation product toxicity was non-mutagenic, non-teratogenic, and devoid of hereditary and non-hereditary carcinogenicity.
研究领域:
环境科学
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化学工程
·
毒理学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2018
·
IF 11.698
Zhenying Jiang,Lingzhi Wang,Juying Lei,Yongdi Liu,Jinlong Zhang
The application of photo-Fenton process is restricted by the acidic pH and additional hydrogen peroxide (H 2 O 2 ). In order to overcome these drawbacks, a photo-Fenton system of CdS/rGO/Fe 2+ which can perform at natural pH with in situ -generated H 2 O 2 has been successfully developed. Highly efficient photo-Fenton degradation of phenol was achieved under the visible light irradiation via the CdS/rGO/Fe 2+ system. Experimental results showed that phenol could be degraded completely in 1 h at natural pH. The plentiful in situ generation of H 2 O 2 was further proved to act as an important role in phenol degradation with the addition of Fe 2+ . The advantages of degradation at natural pH with in situ -generated H 2 O 2 can provide a new prospective to the environmental-friendly Fenton process.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2022
·
IF 14.224
Wei Song,Yuxin Zhou,Zhuoyue Wang,Ji Li,Xiaolei Zhang,Caixia Fu,Xing Du,Zhihong Wang,Wenhui Qiu
Advanced oxidation process (AOPs) is one of the most effective technologies for organic pollutants removal. In this study, diverse reactive species generation and enhanced sulfamethoxazole (SMX) degradation were investigated based on persulfate (PDS) activated by Fe 2+ &dithionite (DTN). When involving Fe 2+ &dithionite in PDS, SMX degradation efficiency reached 84 % within 30 min following a pseudo-first-order kinetic, which was higher than those in Fe 2+ /PDS (50.4 %) and Fe 2+ /O 2 /DTN (41.3 %). SO 4 •− and • OH were identified as dominant reactive species with a crucial role of FeSO 3 + based on quenching experiment and electron spin resonance (ESR). The contributions of SO 4 ·− , · OH, and other species to SMX degradation were 60.1 %, 33.9 %, and 6 %, respectively. In Fe 2+ /DTN/PDS system, SMX was effectively degraded under nearly neutral pH (5.0–9.0), with activation energy of 96.04 kJ·mol −1 . The experiments and density functional theory (DFT) calculation demonstrated that three functional groups (benzenesulfonamido, benzene ring, and oxazole ring) were attacked for SMX degradation. Moreover, acute toxicity to Vibrio fischeri has enhanced in the earlier degradation process due to the intermediates and weaken with the continuous reaction. This work not only provides a high-activity SO 4 ·− -AOP for refractory pollutant treatment with possible dual radical generation resources, but elucidated diverse reactive species formation with Fe 2+ &dithionite.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Chuhan Gu,Lei Song,Maofeng Shi,Yihong Wu,Jiaxian Zhang,Jingyu Lv
In this study, we investigated the efficiency of activation of CaO 2 by oxalic acid (OA) chelated with electrochemically (EF)-released Fe 2+ (EF-CaO 2 /OA) in improving the performance of sludge dewatering under neutral conditions. We also explored the mechanism of OA-reinforcement of EF-CaO 2 in enhancing the performance of wastewater-activated sludge dewatering by investigating the water content (Wc), specific resistance to filtration (SRF), pH, bound water content, extracellular polymers in the sludge, the secondary structure of proteins, the soluble ferric ions, and the morphology of the sludge. The EF-CaO 2 /OA process was better than the EF-CaO 2 process in terms of sludge dewatering. OA introduction significantly inhibited the increase of solution pH, which in turn promoted CaO 2 dissolution and persistent H 2 O 2 generation. The persistent oxidative reaction contributed to the degradation of hydrophilic protein fractions in EPS and the reduction of the proportion of hydrophilic structures in the secondary structure of proteins, which in turn improved the hydrophobicity of the sludge. The changing profile of DNA content in EPS proved that EF-CaO 2 /OA led to the damage of more sludge cells. It suggested that OA enhanced the oxidizing efficacy of EF-CaO 2 , which in turn promoted the release of bound water from more sludge cells. Moreover, OA significantly increased the amount of dissolved iron in solution by chelating the electrochemically released iron, which contributed to the stabilization of the oxidation reaction. Under the optimal conditions, sludge Wc and SRF treated by EF-CaO 2 /OA were reduced by 30.1% and 96.9%, respectively, and the dewatered sludge cake remained neutral. In conclusion, EF-CaO 2 /OA may be an efficient and feasible technique for deep sludge dewatering.
研究领域:
环境科学
·
污水处理
✓ 已验证
DOI
高影响因子
CHEMOSPHERE
·
2021
·
IF 7.086
Jinbin Lin,Junyang Xiao,Hengyu Cai,Yixin Huang,Jiawen Li,Haoyu Yang,Tao Li,Jing Zou
In this study, a multi-wavelength spectrophotometric method for simultaneous determination of peracetic acid (PAA) and coexistent hydrogen peroxide (H 2 O 2 ) was presented. This method was based on the oxidation of 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS) with the assistance of Fe 2+ /KI to produce a stable green radical (ABTS ●+ ), which could be determined at four characteristic peaks (i.e., 415 nm, 650 nm, 732 nm, and 820 nm). The absorbances of ABTS ●+ at four peaks were well linear (R 2 > 0.999) with concentrations of both total peroxides (PAA + H 2 O 2 ) and PAA in the range of 0–40 μM under optimized conditions. The sensitivities for determining total peroxides at 415 nm, 650 nm, 732 nm and 820 nm were determined to be 4.248 × 10 4 M −1 cm −1 , 1.682 × 10 4 M −1 cm −1 , 2.132 × 10 4 M −1 cm −1 , and 1.928 × 10 4 M −1 cm −1 , respectively. For determining PAA, the corresponding sensitivities were 4.622 × 10 4 M −1 cm −1 , 1.895 × 10 4 M −1 cm −1 , 2.394 × 10 4 M −1 cm −1 and 2.153 × 10 4 M −1 cm −1 , respectively. The concentration of coexistent H 2 O 2 was gained by deducting PAA concentration from total peroxides concentration. The ABTS method was accurate enough to determine PAA concentration in natural water samples. Moreover, the ABTS method was successfully used to determine the changes of PAA and coexistent H 2 O 2 and to distinguish their role on naproxen degradation in heat-activated PAA process. Overall, the ABTS method could be used as an alternative method for the convenient, rapid and sensitive determination of PAA and the coexistent H 2 O 2 in water samples.
研究领域:
分析化学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MINERALS ENGINEERING
·
2023
·
IF 4.8
Zhihao Shen,Shuming Wen,Yongchao Miao,Han Wang,Qicheng Feng
Fe 2+ is ubiquitous in flotation pulp and circulating water during the purification of various minerals, and can affect floatation behavior. As such, separating target minerals from gangue minerals can become challenging. In the present work, the flotation performance and resulting surface features of cerussite following exposure to Fe 2+ were systematically and experimentally investigated. Micro-flotation studies indicated that initially introducing Fe 2+ markedly deteriorated the floatability of cerussite when employing a Na 2 S-KIX system. Analyses of using X-ray photoelectron spectroscopy, time-of-flight secondary ion mass spectrometry, inductively coupled plasma optical emission spectrometer, ultraviolet visible spectroscopy, and zeta potential determinations demonstrated that the active sites on the cerussite surfaces were reduced due to Fe 2+ and its hydrophilic derivatives. This effect, in turn, decreased the numbers of highly reactive S-based sulfidization products and attenuated the subsequent interaction of collector with cerussite, thus inhibiting the flotation performance of cerussite.
研究领域:
矿物加工工程
·
表面化学
✓ 已验证
产品关联
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
·
2024
·
IF 5.8
Yirong Fan,Tao Wang,Hui Sun
Metal ion coordination has critical influence on the self-assembly behavior of amphiphilic polymers and the morphology of the obtained assemblies. Herein, an amphiphilic homopolymer with 2,2′-bipyridine (BPy) as side chain is synthesized (noted as PBPyAA), which can self-assemble into bowl-shaped nanoparticles (BNPs) in tetrahydrofuran (THF)/water. Taking advantage of the coordination interaction between BPy and metal ions, Fe 2+ is chosen to regulate the self-assembly behavior and the morphology of the assemblies of PBPyAA in two pathways. (Ⅰ) The aqueous solution of Fe 2+ with various concentrations is added to the THF solution of PBPyAA during self-assembly. (Ⅱ) Fe 2+ is added into the THF solution of PBPyAA before self-assembly, followed by the addition of deionized water to promote the self-assembly. The results show that the pathway Ⅰ facilitates the coordination of BPy and Fe 2+ . With the increase of the concentration of Fe 2+ aqueous solution, the coordination efficiency of BPy increases from 0.419 % to 7.789 %, leading to the transformation of BNPs to vesicles. Though the coordination efficiency of BPy also increases with the concentration of Fe 2+ in pathway Ⅱ, which is still quite low of 0.274 % to 0.366 %, and the morphology of the BNPs barely changes. In addition, ethylene diamine tetraacetic acid (EDTA), a strong chelating agent, is also added to promote the competitive complexation with BPy, resulting in the dissociation of BPy and Fe 2+ and the reversible transformation from vesicles to BNPs. Overall, the effect of Fe 2+ coordination on the self-assembly behavior of PBPyAA in two pathways is investigated and the reversible transformation of BNPs to vesicles is also achieved.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Dequan Wei,Shenghua Lv,Jingjing Zuo,Shan Liang,Jialin Wang,Tingxiang He,Leipeng Liu
Chitosan, as a natural biomass material, is green, recyclable, sustainable and well biocompatible. The molecular chain is rich in active groups such as amino and hydroxyl groups, and its preparation of fluorescent probes has the advantages of biocompatibility and efficient detection performance. In this study, a bis(benzaldehyde) (BHD) fluorescent functional molecule was designed. Then a series of fluorescent chitosan-based hydrogel films (CSBHD) were prepared using chitosan as raw material and BHD as cross-linking agent. As a fluorescent probe for metal ions, CSBHD was able to efficiently detect Fe 2+ with a linear correlation of fluorescence intensity in the range of 0–160 μM, and the limit of detection (LOD) was 0.55 μM. Moreover, it has excellent adsorption performance for Fe 2+ ions, with a maximum adsorption capacity of 223.5 g/mg at 500 mg/L Fe 2+ concentration. Finally, we characterised the structure and microscopic morphology of CSBHD films and found that CSBHD as a hydrogel film has a high cross-linking density, good water resistance, excellent thermal stability, strong resistance to swelling, and excellent stability in cycling tests. Hence, it has great potential for application in adsorption and detection of Fe 2+ ions. It also provides a good strategy for the application of chitosan based fluorescent probe materials in environmental monitoring and heavy metal ion adsorption.
研究领域:
材料科学
·
环境科学
·
生物医学工程
✓ 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）