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Ligand-mediated contaminant degradation by bare and carboxymethyl cellulose-coated bimetallic palladium-zero valent iron nanoparticles in high salinity environments

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Journal of Environmental Sciences 2019年第3期31卷 303-311页

作者： Xiaoming Ma Di He Adele M.Jones T.David Waite Taicheng An Institute of Environmental Health and Pollution Control Guangdong University of Technology Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control School of Environmental Science and Engineering Guangzhou University of Technology School of Civil and Environmental Engineering University of New South Wales

The application of nanoscale zero-valent iron(nZVI) for the degradation of contaminants has been extensively investigated, however, few studies have focused on degradation in high salinity environments. In this study, the ability of bare and carboxymethyl cellulose(CMC)-coated bimetallic Pd-nZVI particles to degrade 33′44′-tetrachlorobiphenyl in high saline water(SW) is examined with particular attention given to the effects of ethylenediaminetetraacetic acid(EDTA) on the rate of degradation. EDTA enhances the reactivity of Pd-nZVI in SW, with evidence provided to link this to the removal of the passivating layer. Additionally, a conceptual model is proposed which provides a quantitative description of the removal of these iron oxide layers in the presence of EDTA. An optimum EDTA to bare Pd-nZVI molar ratio of 0.1 exists, with insufficient EDTA unable to remove the passivating layer whilst excess EDTA results in Fe loss and enhanced agglomeration due to magnetic attraction of the bare Fe(0) particles. In contrast, CMCcoating of Pd-nZVI assemblages actually impedes degradation, despite the coated particles displaying a smaller average size compared to uncoated particles, with even the presence of EDTA in this case not significantly improving degradation. The reduced reactivity in the presence of CMC is primarily attributed to the effect of CMC on the association of Pd with nZVI particles. In particular, the presence of CMC reduced the total amount of Pd incorporated with the stabilized particles compared to the non-stabilized particles.Additionally, the presence of CMC results in less Pd present in its reactive zero-valent oxidation state.

关键词： Bimetallic zero valent iron ligand-mediated depassivation polychlorinated biphenyls high salinity water

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Modified activated carbon with interconnected fibrils of iron-oxyhydroxides using Mn^(2+) as morphology regulator, for a superior arsenic removal from water

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Journal of Environmental Sciences 2019年第2期31卷 403-414页

作者： Cesar Nieto-Delgado Joel Gutiérrez-Martínez J.Rene Rangel-Méndez Environmental Sciences Division Potosino Institute of Scientific and Technological ResearchIPICyT

The arsenic removal efficiency of iron-modified activated carbons depends greatly on the number of available iron oxide surface sites, which are given by the surface area of the anchored particles. In this sense, aiming the generation of an adsorbent with superior arsenic adsorption capacity, we developed a protocol to anchor interconnected fibrils of iron oxyhydroxides, using Mn^(2+) as a morphology regulator. The protocol was based on a microwave-assisted hydrothermal method, using bituminous based activated carbon and both Fe^(2+) and Mn^(2+) ions in the hydrolysis solution. The elemental analysis of modified carbons revealed that Mn does not anchor to the carbon. However, when Mn is included in the hydrolysis solution, the iron content in the activated carbon increased up to 3.5 wt%,without considerable decreasing the adsorbent surface area. Under specific hydrothermal conditions, the Mn^(2+) promoted the formation of iron oxide nanoparticles shaped as interconnected fibrils. This material showed a superior arsenic adsorption capacity in comparison to similar iron modified activated carbons(5 mg As/g carbon, at 2 mg As/L),attributed to the increase in quantity and availability of active sites located on the novel interconnected fibrils of iron oxyhydroxides nanostructures.

关键词： iron oxide nanostructures Hydrothermal synthesis Microwave Adsorption capacity Kinetics

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Stabilization of nanoscale zero-valent iron in water with mesoporous carbon(n ZVI@MC)

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Journal of Environmental Sciences 2019年第7期31卷 28-33页

作者： Junming Shi Jing Wang Wei Wang Wei Teng Wei-xian Zhang State Key Laboratory of Pollution Control and Resource Reuse School of Environmental Science and Engineering Tongji University School of Chemical Science and Engineering Tongji University

Two challenges persist in the applications of nanoscale zero-valent iron(nZVI) for environmental remediation and waste treatment: limited mobility due to rapid aggregation and short lifespan in water due to quick oxidation. Herein, we report the nZVI incorporated into mesoporous carbon(MC) to enhance stability in aqueous solution and mobility in porous media. Meanwhile, the reactivity of nZVI is preserved thanks to high temperature treatment and confinement of carbon framework. Small-sized(～16 nm) nZVI nanoparticles are uniformly dispersed in the whole carbon frameworks. Importantly, the nanoparticles are partially trapped across the carbon walls with a portion exposed to the mesopore channels. This unique structure not only is conductive to hold the nZVI tightly to avoid aggregation during mobility but also provides accessible active sites for reactivity. This new type of nanomaterial contains ～10 wt% of iron. The nZVI@MC possesses a high surface area(～ 500 m^2/g) and uniform mesopores(～ 4.2 nm) for efficient pollutant diffusion and reactions. Also, high porosity of nZVI@MC contributes to the stability and mobility of nZVI. Laboratory column experiments further demonstrate that nZVI@MC suspension(～4 g Fe/L) can pass through sand columns much more efficiently than bare nZVI while the high reactivity of nZVI@MC is confirmed from reactions with Ni(II). It exhibits remarkably better performance in nickel(20 mg/L) extraction than mesoporous carbon, with 88.0% and 33.0%uptake in 5 min, respectively.

关键词： Mesoporous carbon Nanoscale zero-valent iron Mobility Porous media Heavy metal removal

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Evaluation of Erythrocyte iron Incorporation in Beijing Prepubertal Children Using a Single Stable Isotope Tracer Method

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Biomedical and Environmental Sciences 2020年第6期33卷 414-420页

作者： ZHANG Yu LI Ya Jie REN Tong Xiang LIU Xiao Bing YANG Li Chen PAO Jian Hua WANG Jurr YANG Xiao Guang Key Laboratory of Trace Element Nutrition MOHChinese Center for Disease Control and PreventionBeijing 100050China Department of Preventive Medicine Changzhi Medical CollegeChangzhi 046000ShanxiChina National Institute of Metrology Beijing 100029China

Objective To analyze the rate of erythrocyte iron incorporation and provided guidance for the iron nutrition for prepubertal children.Methods Fifty-seven prepubertal children of Beijing were involved in this study and each subject was orally administered 3 mg of 57 Fe twice daily to obtain a total of 30 mg 57 Fe after a 5-d period. The stable isotope ratios in RBCs were determined in 14 th day, 28 th day, 60 th day, and 90 th day. The erythrocyte incorporation rate in children was calculated using the stable isotope ratios, blood volume and body iron mass.Results The percentage of erythrocyte 57 Fe incorporation increased starting 14 th day, reached a peak at 60 d(boys: 19.67% ± 0.56%, girls: 21.33% ± 0.59%) and then decreased. The erythrocyte incorporation rates of 57 Fe obtained for girls in 60 th day was significantly higher than those obtained for boys(P iron incorporation within 90 d. Prepubertal girls should begin to increase the intake of iron and further studies should pay more attention to the iron status in prepubertal children.

关键词： Stable isotope tracer technique iron Erythrocyte incorporation rate Beijing prepubertal children MC-ICP-MS

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Ferrous Oxide Nanoparticles Induced Abnormal Cardiac Development in Zebrafish Through Hypoxia and Ferroptosis

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Chemical Research in Chinese Universities 2023年第3期39卷 502-507页

作者： ZHENG Naying CHEN Xintan ZHAN Ruyu LIAO Tingting SHI Yiyue SUN Xiaolian CHEN Shuzhen ZUO Zhenghong State Key Laboratory of Cellular Stress Biology Xiang’an Hospital of Xiamen UniversitySchool of Life SciencesFaculty of Medicine and Life SciencesXiamen UniversityXiamen361102China Department of Microbiology and Immunology Fujian Provincial Key Laboratory of Functional and Clinical Translational MedicineXiamen Key Laboratory of Respiratory DiseasesXiamen Medical CollegeXiamen361023China Chest Pain Center Anxi County HospitalQuanzhou362400China State Key Laboratory of Natural Medicines Key Laboratory of Drug Quality Control and PharmacovigilanceDepartment of Pharmaceutical AnalysisChina Pharmaceutical UniversityNanjing210009China

Ferrous oxide nanoparticles(nFeO)have potential applications in biomedicine,industrial processes,and waste water treatment.However,the biocompatibility of nFeO remains uncertain.In this study,we synthesized rhombus-shaped nFeO and exposed them to zebrafish embryos to investigate the bio-safety of nFeO.Our results showed that exposure to nFeO led to pericardial edema,heart bleeding,and enlarged ventricles.Furthermore,the content of dissolved oxygen decreased.Fe^(2+)ions,which were released from the core of nFeO,were oxidized into Fe^(3+).This caused the overexpression of tfa and fpn genes,which carried Fe^(3+)into and out of the cell membrane,respectively.The overload of Fe^(3+)caused ferroptosis in zebrafish larvae,which was evidenced by the overexpression of the marker gene ptgs2 and the marker production malondialdehyde(MDA)of ferroptosis.However,neither the ferrostatin-1(Fer-1)inhibitor nor deferoxiamine(DFO)could completely rescue the toxicity caused by nFeO.We found that co-treatment of nFeO with CaO_(2),a dissolved oxygen donor,and Fer-1 or DFO could totally rescue pericardial edema and heart bleeding.Our results provide new knowledge that both hypoxia and ferroptosis play important roles in nFeO-induced zebrafish cardiac developmental toxicity,which is beneficial for the development and safe application of iron-based nanomaterials in the future.

关键词： Nanoparticle Biocompatibility Heart Zebrafish iron

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iron regulatory protein 1: the deadly switch of ferroptosis

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Neural Regeneration Research 2024年第3期19卷 477-478页

作者： Daniel A.Bórquez Pamela J.Urrutia Center for Biomedical Research Faculty of MedicineUniversidad Diego PortalesSantiagoChile Institute of Nutrition&Food Technology(INTA) Universidad de ChileSantiagoChile Geroscience Center for Brain Health and Metabolism SantiagoChile

Ferroptosis,an iron-dependent cell death:Ferroptosis is a type of regulated necrosis,characterized by redox-active iron accumulation and increased free radical production derived by Fenton chemistry,that triggers oxidation of polyunsaturated fatty acids in phospholipids,loss of cellular membranes integrity,and leakage of intracellular contents.

关键词： integrity switch iron

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Axonal iron Transport might Contribute to iron Deposition in Parkinson’s Disease

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Neuroscience Bulletin 2021年第2期37卷 275-277页

作者： Leilei Chen Chong Li Junxia Xie Institute of Brain Science and Disease Shandong Provincial Collaborative Innovation Center for Neurodegenerative DisordersShandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological DisordersQingdao UniversityQingdao 266071China

More and more evidence has suggested that iron deposition in the substantia nigra,which is correlated with motor and cognitive dysfunction,is an important trigger factor,potential biomarker,and therapeutic target for Parkinson's disease(PD)[1-3].Although the cellular mechanisms of nigral iron deposition have been well investigated,the exactly mechanisms,especially the origin of the increased nigral iron,have not been fully elucidated.

关键词： therapeutic exactly iron

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Nanoencapsulation of arsenate with nanoscale zero-valent iron(nZVI):A 3D perspective

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Science Bulletin 2018年第24期63卷 1641-1648页

作者： Airong Liu Wei Wang Jing Liu Rongbing Fu Wei-xian Zhang State Key Laboratory for Pollution Control and Resource Reuse College of Environmental Science and EngineeringTongii UniversityShanghai 200092China School of Chemical Sdence and Engineering Tongji UniversztyShanghai 200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China

The principal forces driving the efficient enrichment and encapsulation of arsenic(As) into nanoscale zero-valent iron(nZVI) are the disordered arrangement of the atoms and the gradient chemical potentials within the core-shell interface. The chemical compositions and the fine structure of nZVI are characterized with a combination of spherical aberration corrected scanning transmission electron microscopy(Cs-STEM), X-ray energy-dispersive spectroscopy(XEDS), electron energy loss spectroscopy(EELS), and high-resolution X-ray photoelectron spectroscopy(HR-XPS). Atomically resolved EELS at the oxygen K-edge unfolds that the Fe species in nZVI are well stratified from Fe(Ⅲ) oxides in the outermost periphery to a mixed Fe(Ⅲ)/Fe(Ⅱ) interlayer, then Fe(Ⅱ) oxide and the pure Fe(0) phase. Reactions between As(Ⅴ)and nZVI suggest that a well-structured local redox gradient exists within the shell layer, which serves as a thermodynamically favorable conduit for electron transfer from the iron core to the surface-bound As(Ⅴ). HR-XPS with ion sputtering shows that arsenic species shift from As(Ⅴ), As(Ⅲ)/As(Ⅴ) to As(Ⅴ)/As(Ⅲ)/As(0) from the iron oxide shell–water interface to the Fe(0) core. Results reinforce previous work on the efficacy of nZVI for removing and remediating arsenic while the analytical TEM methods are also applicable to the study of environmental interfaces and surface chemistry.

关键词： Arsenate Nanoscale zero-valent iron Spherical aberration corrected scanning transmission electron microscopy X-ray energy-dispersive spectroscopy Electron energy-loss spectroscopy X-ray photoelectron spectroscopy

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Determination of Fe^(2+)/Fe^(3+)Ratios of Magnetite using Different Methods:A Case Study from the Qimantag Metallogenic Belt

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Acta Geologica Sinica(English Edition) 2022年第6期96卷 2135-2147页

作者： YI Liwen LI Qiuping LU Anhuai GU Xiangping CHI Guoxiang School of Geographical Sciences Hunan Normal UniversityChangsha 410081China School of Geosciences and Info-Physics Central South UniversityChangsha 410083China School of Earth and Space Sciences Peking UniversityBeijing 100871China Department of Geology University of ReginaReginaSaskatchewan S4S 0A2Canada

Determination of Fe^(2+)/Fe^(3+) ratios from metallogenic belts to explore controlling physical and chemical conditions of rock formation is of great significance.In order to explore magnetite Fe^(2+)/Fe^(3+) ratios of the Qimantag metallogenic belt,part of the Eastern Kunlun orogenic belt in the northeastern margin of the Qinghai–Tibetan plateau,western Central Orogenic Belt of China,and overcome the limitation of the traditional electronic probe,five different measurement methods are proposed and their respective advantages and disadvantages evaluated,with the composition data of the magnetite obtained using electron probe microanalysis(EPMA).The direct oxygen measurement method has a significant impact on the determination results of FeO and Fe2O3,but the accuracy and uniformity of the results are low.The valence method(Flank method)based on the spectral intensity ratio of Lαto Lβfor iron is also unreliable for FeO and Fe_(2)O^(3) measurements because it is difficult to establish a relationship between Lβ/Lα,the spectral intensity ratio,and the Fe^(2+)/Fe^(3+) content ratio.In comparison,the charge difference method,the surplus-oxygen method and the Mössbauer spectrum method are still the most favorable.Mössbauer spectroscopy,with its isomer movement particularly sensitive to the oxidation state of iron,yields results closer to 0.5,which is relatively reliable.Earlier magnetite deposits are located in intrusions or contact zones and formed by magmatic fluids with high Fe2+/Fe3+ratios,whereas later magnetite deposits are farther away from intrusions and have low Fe^(2+)/Fe^(3+) ratios.The transformation mechanism of hematite and magnetite in the Qimantage metallogenic belt is also studied.No large volume changes,such as pore filling and shrinkage fracture,were detected in the metallogenic belt,and the transformation mechanism is more similar to a reoxidation and reduction mechanism.

关键词： iron magnetite direct oxygen measurement flank-charge difference-surplus-oxygen methods Mössbauer spectra Qimantage

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Bio-inspired tetracarbene compounds as a new family of energy saving catalysts

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Journal of Energy Chemistry 2023年第4期79卷 559-561页

作者： Bo Zhang Fritz E.Kühn CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina' University of Chinese Academy of Science Beijing 100049China Molecular Catalysis Catalysis Research Center and Department of ChemistrySchool of Natural SciencesTechnical University of MunichLichtenbergstr 485748 Garching bei MünchenGermany

Efficient use of energy is a pressing issue.Improvement of chemical processes is currently an important target for energy efficiency.Although chemical processes are independent of pathways with respect to the final energy output or consumption,the application of catalysts can reduce involved activation energies considerably and therefore save large amounts of energy.

关键词： Catalysis iron Carbenes Multidentate ligands

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