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Constructing fast mass-transfer channels with efficient catalytic ozonation activity in 2D manganese dioxide membranes by intercalating Fe/Mn bimetallic MOF
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作者 Dandan Zhou Shilong Li +4 位作者 Luyi Chai Jian Lu Tianxiang Yu Yuqing Sun Wenheng Jing 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第10期272-286,共15页
Two-dimensional(2D)catalytic ozonation membranes are promising for the treatment of micropollutants in wastewater due to simultaneous ozone-catalyzed degradation and membrane filtration processes.However,it remains ch... Two-dimensional(2D)catalytic ozonation membranes are promising for the treatment of micropollutants in wastewater due to simultaneous ozone-catalyzed degradation and membrane filtration processes.However,it remains challenging for 2D catalytic ozonation membranes to efficiently degrade micropollutants due to low mass-transfer efficiency and poor catalytic activity.Herein,Fe/Mn bimetallic metal-organic framework(MOF)intercalated lamellar MnO_(2) membranes with fast and robust ozone-catalyzed mass-transfer channels were developed on the surface of the hollow fiber ceramic membrane(HFCM)to obtain 2D Fe/Mn-MOF@MnO_(2)-HFCM for efficiently degrading micropollutants in wastewater.The intercalation of Fe/Mn-MOF expanded the interlayer spacing of the MnO_(2) membrane,thereby providing abundant transport channels for rapid passage of water.More notably,the Fe/Mn-MOF provided enriched reactive sites as well as high electron transfer efficiency based on the redox cycling between Mn^(3+)/Mn^(4+) and Fe^(2+)/Fe^(3+),ensuring the effective catalytic oxidative degradation of micropollutants including tetracycline hydrochloride(TCH),methylene blue,and methyl blue.Moreover,the carboxyl groups on the MOF formed covalent bonds(-COO-)with the hydroxyl groups in MnO_(2) between layers,which increased the interaction between MnO_(2) nanosheets to form stable interlayer channels.Specifically,the optimal composite membrane achieved a high removal rate of TCH micropollutant(93.4%),high water treatment capacity(282 L·m^(-2)·h^(-1)·MPa^(-1)),and excellent longterm stability(1200 min).This study provides a simple and easily scalable strategy to construct fast,efficient,and stable 2D catalytic mass-transfer channels for the efficient treatment of micropollutants in wastewater. 展开更多
关键词 Catalytic ozonation Two-dimensional ceramic membranes Fe/mn bimetallic MOF MICROPOLLUTANTS
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Heterointerface Engineering-Induced Oxygen Defects for the Manganese Dissolution Inhibition in Aqueous Zinc Ion Batteries 被引量:2
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作者 Wentao Qu Yong Cai +1 位作者 Baohui Chen Ming Zhang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第3期112-122,共11页
Manganese-based material is a prospective cathode material for aqueous zinc ion batteries(ZIBs)by virtue of its high theoretical capacity,high operating voltage,and low price.However,the manganese dissolution during t... Manganese-based material is a prospective cathode material for aqueous zinc ion batteries(ZIBs)by virtue of its high theoretical capacity,high operating voltage,and low price.However,the manganese dissolution during the electrochemical reaction causes its electrochemical cycling stability to be undesirable.In this work,heterointerface engineering-induced oxygen defects are introduced into heterostructure MnO_(2)(δa-MnO_(2))by in situ electrochemical activation to inhibit manganese dissolution for aqueous zinc ion batteries.Meanwhile,the heterointerface between the disordered amorphous and the crystalline MnO_(2)ofδa-MnO_(2)is decisive for the formation of oxygen defects.And the experimental results indicate that the manganese dissolution ofδa-MnO_(2)is considerably inhibited during the charge/discharge cycle.Theoretical analysis indicates that the oxygen defect regulates the electronic and band structure and the Mn-O bonding state of the electrode material,thereby promoting electron transport kinetics as well as inhibiting Mn dissolution.Consequently,the capacity ofδa-MnO_(2)does not degrade after 100 cycles at a current density of 0.5 Ag^(-1)and also 91%capacity retention after 500cycles at 1 Ag^(-1).This study provides a promising insight into the development of high-performance manganese-based cathode materials through a facile and low-cost strategy. 展开更多
关键词 electrochemical activation HETEROINTERFACE manganese dissolution inhibition oxygen defects zinc ion batteries
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Facile synthesis of Cu-doped manganese oxide octahedral molecular sieve for the efficient degradation of sulfamethoxazole via peroxymonosulfate activation 被引量:1
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作者 Yuhua Qiu Yingping Huang +2 位作者 Yanlan Wang Xiang Liu Di Huang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第12期2770-2780,共11页
Advanced processes for peroxymonosulfate(PMS)-based oxidation are efficient in eliminating toxic and refractory organic pol-lutants from sewage.The activation of electron-withdrawing HSO_(5)^(-)releases reactive speci... Advanced processes for peroxymonosulfate(PMS)-based oxidation are efficient in eliminating toxic and refractory organic pol-lutants from sewage.The activation of electron-withdrawing HSO_(5)^(-)releases reactive species,including sulfate radical(·SO_(4)^(-)),hydroxyl radical(·OH),superoxide radical(·O_(2)^(-)),and singlet oxygen(1O_(2)),which can induce the degradation of organic contaminants.In this work,we synthesized a variety of M-OMS-2 nanorods(M=Co,Ni,Cu,Fe)by doping Co^(2+),Ni^(2+),Cu^(2+),or Fe^(3+)into manganese oxide oc-tahedral molecular sieve(OMS-2)to efficiently remove sulfamethoxazole(SMX)via PMS activation.The catalytic performance of M-OMS-2 in SMX elimination via PMS activation was assessed.The nanorods obtained in decreasing order of SMX removal rate were Cu-OMS-2(96.40%),Co-OMS-2(88.00%),Ni-OMS-2(87.20%),Fe-OMS-2(35.00%),and OMS-2(33.50%).Then,the kinetics and struc-ture-activity relationship of the M-OMS-2 nanorods during the elimination of SMX were investigated.The feasible mechanism underly-ing SMX degradation by the Cu-OMS-2/PMS system was further investigated with a quenching experiment,high-resolution mass spec-troscopy,and electron paramagnetic resonance.Results showed that SMX degradation efficiency was enhanced in seawater and tap water,demonstrating the potential application of Cu-OMS-2/PMS system in sewage treatment. 展开更多
关键词 SULFAMETHOXAZOLE manganese oxide octahedral molecular sieve PEROXYMONOSULFATE sewage treatment COPPER
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Mn/beta and Mn/ZSM-5 for the low-temperature selective catalytic reduction of NO with ammonia: Effect of manganese precursors 被引量:12
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作者 Wenjin Xu Guangxu Zhang +4 位作者 Hanwei Chen Guomeng Zhang Yang Han Yichuan Chang Peng Gong 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第1期118-127,共10页
Two series of Mn/beta and Mn/ZSM‐5catalysts were prepared to study the influence of how different Mn precursors,introduced to the respective parent zeolites by wet impregnation,affected the selective catalytic reduct... Two series of Mn/beta and Mn/ZSM‐5catalysts were prepared to study the influence of how different Mn precursors,introduced to the respective parent zeolites by wet impregnation,affected the selective catalytic reduction(SCR)of NO by NH3across a low reaction temperature window of50–350°C.In this study,the catalysts were characterized using N2adsorption/desorption,X‐ray diffraction,X‐ray fluorescence,H2temperature‐programmed reduction,NH3temperature‐programmed desorption and X‐ray photoelectron spectroscopy.As the manganese chloride precursor only partially decomposed this primarily resulted in the formation of MnCl2in addition to the presence of low levels of crystalline Mn3O4,which resulted in poor catalytic performance.However,the manganese nitrate precursor formed crystalline MnO2as the major phase in addition to a minor presence of unconverted Mn‐nitrate.Furthermore,manganese acetate resulted principally in a mixture of amorphous Mn2O3and MnO2,and crystalline Mn3O4.From all the catalysts screened,the test performance data showed Mn/beta‐Ac to exhibit the highest NO conversion(97.5%)at240°C,which remained>90%across a temperature window of220–350°C.The excellent catalytic performance was ascribed to the enrichment of highly dispersed MnOx(Mn2O3and MnO2)species that act as the active phase in the NH3‐SCR process.Furthermore,together with a suitable amount of weakly acidic centers,higher concentration of surface manganese and a greater presence of surface labile oxygen groups,SCR performance was collectively enhanced at low temperature.?2018,Dalian Institute of Chemical Physics,Chinese Academy of Sciences.Published by Elsevier B.V.All rights reserved. 展开更多
关键词 mn/beta mn/ZSM‐5 Low‐temperature Catalytic performance Selective catalytic reduction manganese precursors
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Treatment of mine water high in Fe and Mn by modified manganese sand 被引量:9
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作者 HE Xuwen YANG Huimin HE Yong 《Mining Science and Technology》 EI CAS 2010年第4期571-575,共5页
The iron and manganese absorption properties of several filter media were studied. Four plain filter media and six surface-modified media were examined. The surface modification was performed using potassium permangan... The iron and manganese absorption properties of several filter media were studied. Four plain filter media and six surface-modified media were examined. The surface modification was performed using potassium permanganate as a surface treatment. The surface-modified manganese sand was found to be most efficient at removing iron and manganese from water. The metal concentrations in filtered effluent were between 0.01 and 0.04 mg/L, which is far lower than the standard for recycle water. A concen-tration of 5% KMnO4 was found to be most effective as surface modifier. The surface of the manganese sand modified by 5% KMnO4 was examined and found to be covered with a dense membrane of some compound. The membrane had the advantages of uniform texture, large surface area and physical and chemical stability. It was effective at removing iron and manganese from mine water. 展开更多
关键词 mine water with high Fe and mn FILTRATION manganese sand media KmnO4 solution surface-modified
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Mechanism of Capacity Fading Caused by Mn(Ⅱ)Deposition on Anodes for Spinel Lithium Manganese Oxide Cell 被引量:7
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作者 陈海辉 MA Tianyi +2 位作者 ZENG Yingying GUO Xiuyan 邱新平 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2017年第1期1-10,共10页
The capacity fade of spinel lithium manganese oxide in lithium-ion batteries is a bottleneck challenge for the large-scale application.The traditional opinion is that Mn(Ⅱ) ions in the anode are reduced to the meta... The capacity fade of spinel lithium manganese oxide in lithium-ion batteries is a bottleneck challenge for the large-scale application.The traditional opinion is that Mn(Ⅱ) ions in the anode are reduced to the metallic manganese that helps for catalyzing electrolyte decomposition.This could poison and damage the solid electrolyte interface(SEI) film,leading to the the capacity fade in Li-ion batteries.We propose a new mechanism that Mn(Ⅱ) deposites at the anode hinders and/or blocks the intercalation/de-intercalation of lithium ions,which leads to the capacity fade in Li-ion batteries.Based on the new mechanism assumption,a kind of new structure with core-shell characteristic is designed to inhabit manganese ion dissolution,thus improving electrochemical cycle performance of the cell.By the way,this mechanism hypothesis is also supported by the results of these experiments.The LiMn2-xTixO4 shell layer enhances cathode resistance to corrosion attack and effectively suppresses dissolution of Mn,then improves battery cycle performance with LiMn_2O_4 cathode,even at high rate and elevated temperature. 展开更多
关键词 capacity fade manganese deposition lithium manganese oxide core-shell structure
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Covalency competition induced selective bond breakage and surface reconstruction in manganese cobaltite towards enhanced electrochemical charge storage 被引量:1
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作者 Peng Gao Pei Tang +7 位作者 Ying Mo Peitao Xiao Wang Zhou Shi Chen Hongliang Dong Ziwei Li Chaohe Xu Jilei Liu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第5期909-918,共10页
Manganese cobaltite(MnCo_(2)_(4))is a promising electrode material because of its attractive redox chemistry and excellent charge storage capability.Our previous work demonstrated that the octahedrally-coordinated Mn ... Manganese cobaltite(MnCo_(2)_(4))is a promising electrode material because of its attractive redox chemistry and excellent charge storage capability.Our previous work demonstrated that the octahedrally-coordinated Mn are prone to react with the hydroxyl ions in alkaline electrolyte upon electrochemical cycling and separates on the surface of spinel to reconstruct into d-MnO_(2) nanosheets irreversibly,thus results in a change of the reaction mechanism with Kþion intercalation.However,the low capacity has greatly limited its practical application.Herein,we found that the tetrahedrally-coordinated Co_(2) þions were leached when MnCo_(2)_(4) was equilibrated in 1 mol L^(-1) HCl solution,leading to the formation of layered CoOOH on MnCo_(2)_(4) surface which is originated from the covalency competition induced selective breakage of the CoT–O bond in CoT–O–CoO and subsequent rearrangement of free Co_(6) octahedra.The as-formed CoOOH is stable upon cycling in alkaline electrolyte,exhibits conversion reaction mechanism with facile proton diffusion and is free of massive structural evolution,thus enables utilization of the bulk electrode material and realizes enhanced specific capacity as well as facilitated charge transfer and ion diffusion.In general,our work not only offers a feasible approach to deliberate modification of MnCo_(2)_(4)'s surface structure,but also provides an in-depth understanding of its charge storage mechanism,which enables rational design of the spinel oxides with promising charge storage properties. 展开更多
关键词 manganese cobaltite Tetrahedrally-coordinated Co^(2+)leaching Selective bond breakage Surface reconstruction Charge storage mechanisms
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Cobalt and manganese stress in the microalga Pavlova viridis (Prymnesiophyceae):Effects on lipid peroxidation and antioxidant enzymes 被引量:9
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作者 LI Mei ZHU Qin +3 位作者 HU Chang-wei CHEN Li LIU Zhi-li KONG Zhi-ming 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第11期1330-1335,共6页
Pollution of marine environment has become an issue of major concern in recent years. Serious environmental pollution by heavy metals results from their increasing utilization in industrial processes and because most ... Pollution of marine environment has become an issue of major concern in recent years. Serious environmental pollution by heavy metals results from their increasing utilization in industrial processes and because most heavy metals are transported into the marine environment and accumulated without decomposition. The aim of the present study is to investigate the effects on growth, pigments, lipid peroxidation, and some antioxidant enzyme activities of marine microalga Pavlova viridis, in response to elevated concentrations of cobalt (Co) and manganese (Mn), especially with regard to the involvement of antioxidative defences against heavy metal-induced oxidative stress. In response to Co^2+, lipid peroxidation was enhanced compared to the control, as an indication of the oxidative damage caused by metal concentration assayed in the microalgal cells but not Mn^2+. Exposure of Pavlova viridis to the two metals caused changes in enzyme activities in a different manner, depending on the metal assayed: after Co^2+ treatments, total superoxide dismutase (SOD) activity was irregular, although it was not significantly affected by Mn^2+ exposure. Co^2+ and Mn^2+ stimulated the activities of catalase (CAT) and glutathione (GSH), whereas, glutathione peroxidase (GPX) showed a remarkable increase in activity in response to Co^2+ treatments and decreased gradually with Mn^2+ concentration, up to 50 μmol/L, and then rose very rapidly, reaching to about 38.98% at 200 μmol/L Mn^2+. These results suggest that an activation of some antioxidant enzymes was enhanced, to counteract the oxidative stress induced by the two metals at higher concentration. 展开更多
关键词 antioxidant enzymes COBALT manganese malondialdehyde (MDA) Pavlova viridis
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Synthesis and Crystal Structure of a New Two-dimensional Manganese Coordination Polymer:[Mn(L)(1,4-bdc)] 被引量:9
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作者 孔治国 马晓媛 +1 位作者 徐占林 王秀艳 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第7期927-930,共4页
A new coordination polymer, [Mn(L)(1,4-bdc)] (L = 11-fluoro-dipyrido[3,2- a:2",3 "- c]phenazine, 1,4-bdc - benzene-1,4-dicarboxylate), has been synthesized through the hydrothermal method and characterized by... A new coordination polymer, [Mn(L)(1,4-bdc)] (L = 11-fluoro-dipyrido[3,2- a:2",3 "- c]phenazine, 1,4-bdc - benzene-1,4-dicarboxylate), has been synthesized through the hydrothermal method and characterized by elemental analysis, IR and single-crystal X-ray diffraction. It crystallizes in triclinic, space group P1 with a = 9.7544(9), b = 10.8254(10), c = 11.5288(10) A, a = 114.1300(10), β = 96.6110(10), y = 105.0390(10)°, V= 1038.62(16)/k3, Z= 2, C26H13FMnN404, Mr = 519.34, Dc = 1.661 g/cm3, F(000) = 526, ,u(MoKa) = 0.691 mm^-, R = 0.0405 and wR = 0.0977. The 1,4-bdc dianions link the neighboring Mn(II) atoms to yield a two-dimensional layer structure. The L ligands are attached on both sides of the layer. The π-π interactions between the L ligands of neighboring layers result in a three-dimensional supramolecular architecture. 展开更多
关键词 manganese complex crystal structure coordination polymer
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Synthesis of amorphous manganese borohydride in the(NaBH_4–MnCl_2) system, its hydrogen generation properties and crystalline transformation during solvent extraction 被引量:1
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作者 Robert A.Varin Deepak K.Mattar +1 位作者 Amirreza Shirani Bidabadi Marek Polanski 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2017年第1期24-34,共11页
The mixture of(2NaBH4+ MnCl2) was ball milled in a magneto-mill. No gas release was detected. The XRD patterns of the ball milled mixture exhibit only the Bragg diffraction peaks of the Na Cl-type salt which on the ba... The mixture of(2NaBH4+ MnCl2) was ball milled in a magneto-mill. No gas release was detected. The XRD patterns of the ball milled mixture exhibit only the Bragg diffraction peaks of the Na Cl-type salt which on the basis of the present X-ray diffraction results and the literature is likely to be a solid solution Na(Cl)x(BH4)(1-x), possessing a cubic Na Cl-type crystalline structure. No presence of any crystalline hydride was detected by powder X-ray diffraction which clearly shows that NaBH4in the initial mixture must have reacted with MnCl2forming a Na Cl-type by-product and another hydride that does not exhibit X-ray Bragg diffraction peaks. Mass spectrometry(MS) of gas released from the ball milled mixture during combined MS/thermogravimetric analysis(TGA)/differential scanning calorimetry(DSC) experiments, confirms mainly hydrogen(H2) with a small quantity of diborane gas, B2H6. The Fourier transform infra-red(FT-IR) spectrum of the ball milled(2NaBH4+ MnCl2) is quite similar to the FT-IR spectrum of crystalline manganese borohydride, c-Mn(BH4)2, synthesized by ball milling, which strongly suggests that the amorphous hydride mechano-chemically synthesized during ball milling could be an amorphous manganese borohydride. Remarkably, the process of solvent filtration and extraction at 42 °C, resulted in the transformation of mechano-chemically synthesized amorphous manganese borohydride to a nanostructured,crystalline, c-Mn(BH4)2hydride. 展开更多
关键词 Ball milling Mechano-chemical activation synthesis Amorphous manganese borohydride mn(BH4)2 Dehydrogenation behavior Solvent extraction Crystallization of manganese borohydride mn(BH4)2
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Effects of carrier and Mn loading on supported manganese oxide catalysts for catalytic combustion of methane 被引量:3
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作者 Jinyan Hu Wei Chu Limin Shi 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2008年第2期159-164,共6页
Supported manganese oxide catalysts were prepared by incipient wetness impregnation method for methane catalytic combustion, and effects of the support (Al2O3, SiO2 and TiO2) and Mn loading were investigated. These ... Supported manganese oxide catalysts were prepared by incipient wetness impregnation method for methane catalytic combustion, and effects of the support (Al2O3, SiO2 and TiO2) and Mn loading were investigated. These catalysts were characterized with N2 adsorption, X-ray diffraction, X-ray photoelectron spectroscopy and temperature-programmed reduction techniques. Methane conversion varied in a large range depending on supports or Mn loading. Al2O3 supported 15% Mn catalyst exhibited better activity toward methane catalytic oxidation. The manganese state and oxygen species played an important role in the catalytic performance, 展开更多
关键词 methane catalytic combustion manganese oxide catalyst support effect ALUMINA
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Removal of Uranium(Ⅵ) by Fixed Bed Ion-exchange Column Using Natural Zeolite Coated with Manganese Oxide 被引量:18
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作者 邹卫华 赵蕾 韩润平 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第4期585-593,共9页
The adsorption of uranium(Ⅵ)on the manganese oxide coated zeolite(MOCZ)from aqueous solution was investigated in a fixed-bed column.The experiments were conducted to investigate the effects of bed height,flow rate,pa... The adsorption of uranium(Ⅵ)on the manganese oxide coated zeolite(MOCZ)from aqueous solution was investigated in a fixed-bed column.The experiments were conducted to investigate the effects of bed height,flow rate,particle size,initial concentration of uranium(Ⅵ),initial pH,presence of salt and competitive ions.The U-uptake by MOCZ increased with initial uranium(Ⅵ)concentration and bed height,but decreased as the flow rate and particle size increased.In the presence of salt and competitive ions,the breakthrough time was shorter.The adsorption capacity reached a maximum at pH of 6.3.The Thomas model was applied to the experimental data to determine the characteristic parameters of the column for process design using linear regression.The breakthrough curves calculated from the model were in good agreement with the experimental data.The BDST model was used to study the influence of bed height on the adsorption of uranium(Ⅵ).Desorption of uranium(Ⅵ)in the MOCZ column was investigated.The column could be used for at least four adsorption-desorption cycles using 0.1mol.L-1 NaHCO3 solution as the elution.After desorption and regeneration with deionized water,MOCZ could be reused to adsorb uranium(Ⅵ)at a comparable capacity.Compared to raw zeolite,MOCZ showed better capacity for uranium(Ⅵ)removal. 展开更多
关键词 ADSORPTION uranium (Ⅵ) manganese oxide coated zeolite REGENERATION
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Synthesis, Crystal Structure and Spectrum Properties of Trinuclear Manganese Coordination Compound Mn_3(2,2'-bipy)_2(3,5-DMBA)_6 被引量:3
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作者 李薇 李昶红 +1 位作者 李玉林 张春华 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第10期1507-1511,共5页
A novel complex Mn3(2,2'-bipy)ff3,5-DMBA)6 with 3,5-dimethylbenzoic acid (3,5-DMBA) and 2,2'-bipyridine (2,2'-bipy) has been synthesized by means of a solvent method. It crystallizes in the monoclinic space ... A novel complex Mn3(2,2'-bipy)ff3,5-DMBA)6 with 3,5-dimethylbenzoic acid (3,5-DMBA) and 2,2'-bipyridine (2,2'-bipy) has been synthesized by means of a solvent method. It crystallizes in the monoclinic space group C2/c with a = 3.1118(6), b = 1.1754(2), c = 2.0887(4) nm, β = 118.50(3)°, V= 6.714(2) nm3, Dc = 1.384 g/cm3, Z = 8, F(000) = 2912, the final GOOF = 1.078, R = 0.0691 and wR = 0.1455. The crystal structure shows that the three coordinated manganese(II) ions lie in a line with the middle one as the symmetric center. The distance between the central manganese(II) and the symmetric one is 0.3549 nm. There exist two coordination modes for the three manganese (II) ions: the symmetric manganese(II) ions are coordinated with three oxygen atoms and two nitrogen atoms from three 3,5-DMBA molecules and one 2,2'-bipy molecule, respectively, forming a distorted square-pyramidal coordination geometry; the middle manganese(II) ion is coordinated with six oxygen atoms from six 3,5-DMBA molecules, generating a distorted octahedral coordination geometry. Spectrum properties of the complex were also studied. 展开更多
关键词 trinuclear manganese(II) complex crystal structure spectrum properties
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On-line Preconcentration of Trace Nickel from Electrolytic Manganese Using Minicolumn Packed Activated Carbon for Electrothermal Atomic Absorption Spectrometry 被引量:2
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作者 姚俊 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2004年第4期17-20,共4页
The online flow injection preconcentration and electrothermal atomic absorption spectrometry method were used for the determination of trace nickel in electrolytic manganese samples by sorption on a conical minicolumn... The online flow injection preconcentration and electrothermal atomic absorption spectrometry method were used for the determination of trace nickel in electrolytic manganese samples by sorption on a conical minicolumn packed with activated carbon at pH 9.0. The nickel was eluted from the minicolumn with 10%(v/v) nitric acid. An enrichment factor of 190-fold for a sample volume of 10mL was obtained. The detection limit (DL) of nickel with the use of the preconcentration method was 13ng·g -1in the original solid sample. The precision for 10 replicate determinations at 150ng·g -1 nickel concentration was 5.2% relative standard deviation (RSD). The calibration graph was linear with a correlation coefficient of r=0.9996 up to concentration of 660ng·g -1 nickel. 展开更多
关键词 online preconcentration NICKEL electrothermal atomic absorption spectrometry activated carbon electrolytic manganese
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Synthesis and Crystal Structure of a Novel Three-dimensional Manganese(Ⅱ) Coordination Polymer:[Mn(pdc)]_n (pdc=Pyridine-2,4-dicarboxylate) 被引量:2
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作者 ZHANG Chun-Xia MA Cheng-Bing +1 位作者 WANG Mei CHEN Chang-Neng 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第2期245-249,共5页
A novel manganese(H) coordination polymer [Mn(pdc)]n (pdc = pyridine-2,4- dicarboxylate) has been synthesized under hydrothermal conditions. The crystal is of monoclinic, space group P211n with a = 6.506(4), b... A novel manganese(H) coordination polymer [Mn(pdc)]n (pdc = pyridine-2,4- dicarboxylate) has been synthesized under hydrothermal conditions. The crystal is of monoclinic, space group P211n with a = 6.506(4), b = 9.392(6), c = 11.217(7) A, β = 105.650(12)°, V= 660.0(7)A3, Z = 4, Mr = 220.04, Dc = 2.215 g/cm3,μ = 1.971 mm-1, F(000) = 436, Rint = 0.0345, R = 0.0360 and wR = 0.0778 for 1259 observed reflections with I 〉 2σ(I). In the structure, the Mn(Ⅱ) atom is coordinated in a distorted octahedral arrangement by one pyridine N and five carboxylate O atoms from five pdc ligands, each of which coordinates to five Mn atoms to propagate a three-dimensional layered framework. 展开更多
关键词 manganese complex crystal structure 3-D network
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新型含Mn生物陶瓷粉体减轻软骨细胞的氧化应激损伤
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作者 张梓宁 邓荣辉 余家阔 《中国组织工程研究》 CAS 北大核心 2025年第16期3335-3342,共8页
背景:Mn可参与到多种生物体内氧化还原反应中,比如作为超氧化物歧化酶2中的金属辅助基团发挥辅助清除活性氧的作用,因此近些年开发含Mn的新型抗氧化应激材料成为研究的热点。目的:探讨含Mn生物陶瓷粉体通过降低活性氧途径对软骨细胞氧... 背景:Mn可参与到多种生物体内氧化还原反应中,比如作为超氧化物歧化酶2中的金属辅助基团发挥辅助清除活性氧的作用,因此近些年开发含Mn的新型抗氧化应激材料成为研究的热点。目的:探讨含Mn生物陶瓷粉体通过降低活性氧途径对软骨细胞氧化应激损伤的保护作用。方法:采用熔盐法制备含Mn生物陶瓷粉体。分离培养小鼠原代软骨细胞。在H_(2)O_(2)溶液中分别加入含0,0.15,0.30 mg/mL Mn生物陶瓷粉体,避光孵育后检测H_(2)O_(2)清除率。将第2-4代软骨细胞分别与含不同质量浓度(0,0.15,0.30 mg/mL)含Mn生物陶瓷粉体的完全培养基共培养,采用细胞活死染色检测细胞活性。将第2-4代软骨细胞(或软骨组织)分4组干预:空白对照组加入完全培养基培养,H_(2)O_(2)组加入用含H_(2)O_(2)的完全培养基培养,H_(2)O_(2)+低质量浓度Mn粉体组加入含H_(2)O_(2)+0.15 mg/mL含Mn生物陶瓷粉体的完全培养基培养,H_(2)O_(2)+高质量浓度Mn粉体组加入含H_(2)O_(2)+0.30 mg/mL含Mn生物陶瓷粉体的完全培养基,采用CCK-8法检测软骨细胞活力,2,7-二氯荧光素二乙酸酯探针检测软骨细胞活性氧生成,qRT-PCR检测软骨细胞相关因子表达,甲苯胺蓝染色检测软骨组织结构与功能。结果与结论:①两种剂量的含Mn生物陶瓷粉体均可以于体外显著清除H_(2)O_(2),并且具有质量浓度依赖性;细胞活死染色结果显示,0.15 mg/mL含Mn生物陶瓷粉体具有软骨细胞安全性,0.30 mg/mL含Mn生物陶瓷粉体存在软骨细胞毒性;②CCK-8检测结果显示,两种质量浓度的含Mn生物陶瓷粉体均可以显著减轻H_(2)O_(2)对软骨细胞活力的抑制作用,并可抑制H_(2)O_(2)诱导的软骨细胞活性氧生成,并且具有质量浓度依赖性;两种质量浓度的含Mn生物陶瓷粉体均可逆转H_(2)O_(2)诱导的软骨细胞血小板反应蛋白解整合素金属肽酶5 mRNA表达升高与蛋白聚糖mRNA表达降低;③甲苯胺蓝染色结果显示,两种质量浓度的含Mn生物陶瓷粉体均可保护氧化应激下软骨组织结构的完整,其中0.30 mg/mL含Mn生物陶瓷粉体还可以减轻软骨组织的功能损伤;④结果表明,含Mn生物陶瓷粉体可以通过清除活性氧途径维持软骨细胞外基质稳态,从而对氧化应激下的软骨细胞发挥保护作用,但0.30 mg/mL含Mn生物陶瓷粉体具有一定的软骨细胞毒性,因此更倾向使用0.15 mg/mL含Mn生物陶瓷粉体进行后续研究。 展开更多
关键词 生物陶瓷 mn粉体材料 软骨损伤 氧化应激 活性氧 骨关节炎 细胞外基质 生物安全性
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Tuning electronic structure ofδ-MnO_(2) by the alkali-ion(K,Na,Li)associated manganese vacancies for high-rate supercapacitors 被引量:2
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作者 Lengyuan Niu Lijin Yan +5 位作者 Zhengwei Lu Yinyan Gong Taiqiang Chen Can Li Xinjuan Liu Shiqing Xu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第5期245-258,共14页
Cation vacancies can bring numerous surprising characters due to its multifarious electron and orbit distribution.In this work,d-MnO_(2) with alkali-ion(K,Na,Li)associated manganese(Mn)vacancies is fabricated by a sim... Cation vacancies can bring numerous surprising characters due to its multifarious electron and orbit distribution.In this work,d-MnO_(2) with alkali-ion(K,Na,Li)associated manganese(Mn)vacancies is fabricated by a simple hydrothermal reaction,and the correlation between their electronic structure and pseudocapacitance are systematically investigated.FESEM/TEM images have shown that the morphology of MnO_(2) is obviously changed after the introducing of cation vacancies.The position of alkali-ion in MnO_(2) structure can be controlled by adjusting the ion concentration.XRD patterns and Raman spectra demonstrate that the alkali-ion is embedded in Mn vacancies at low concentration,while entered the interlayer of MnO_(2) at high concentration.The existence of Mn vacancies will resulting in the distortion of neighboring atoms,leading to the electronic delocalization,and thus enhancing the conductivity,pseudocapacitance and rate capability of MnO_(2).Accordingly,the specific capacitances of optimized 0.4 KMO,0.4 NaMO and 0.4 LiMO samples are enhanced about 1.9,1.6 and 1.6 times compared to pure MnO_(2).Meanwhile,the rate performance has also been improved about 76%,46%and 42%,respectively.Theoretical calculations further confirm that the Mn vacancies can generate additional occupancy states and cause an increase in carrier concentration,which will improve the conductivity and further boost the pseudocapacitance of MnO_(2).This result open up a promising approach to explore active and durable electrode materials. 展开更多
关键词 SUPERCAPACITOR manganese oxide manganese vacancies PSEUDOCAPACITANCE
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Synthesis,Crystal Structure and Magnetic Behavior of a New Manganese(Ⅱ) Coordination Polymer [Mn(DPPZ)(PZDC)(H_2O)] (DPPZ=Dipyrido[3,2-a:2',3'-c]-phenazine and H_2PZDC=Pyrazine-2,3-dicarboxylic Acid) 被引量:6
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作者 徐占林 李秀颖 +2 位作者 车广波 刘春波 王庆伟 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第5期593-597,共5页
The title complex, [Mn(DPPZ)(PZDC)(H2O)] 1 (DPPZ = dipyrido[3,2 -a:2',3'- c]phenazine and H2PZDC = pyrazine-2,3-dicarboxylic acid), has been hydrothermally synthesized and structurally characterized by X-ra... The title complex, [Mn(DPPZ)(PZDC)(H2O)] 1 (DPPZ = dipyrido[3,2 -a:2',3'- c]phenazine and H2PZDC = pyrazine-2,3-dicarboxylic acid), has been hydrothermally synthesized and structurally characterized by X-ray single-crystal diffraction, elemental analyses, IR, TG- DTA and magnetic susceptibility measurement. It crystallizes in triclinic, space group P1^- with a = 6.6842(5), b = 7.5741(6), c = 20.5755(15)A, α = 90.1160(10), β = 97.0560(10), γ = 97.3350(10)°, V= 1025.16(13)A^3, Z = 2, MnC24H14N6O5, Mr= 521.35, Dc= 1.689 g/cm^3, F(000) = 530, μ(MoKa) = 0.699 mm^-1, R = 0.0366 and wR = 0.0810. Compound 1 contains one- dimensional chains which are further stacked through π-π interactions to form a 3D supramolecular architecture. The water molecule O(1W) is involved in hydrogen bonding interactions with symmetric carboxylate oxygen atom 0(4) at (x+ 1, y+1, z) and symmetric PZDC nitrogen atom N(6) at (1-x, 1-y, 1-z), which completes the structure of 1. Magnetic susceptibility measurement indicates that the compound behaves a weak antiferromagnetic exchange interaction. 展开更多
关键词 manganese complex magnetic property dipyrido[3 2-a:2' 3'-c]phenazine pyrazine-2 3-dicarboxylic acid
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Hydrothermal Synthesis and Crystal Structure of a Manganese(Ⅱ) Complex:Mn_(1.5)(cbba)_3(phen) 被引量:2
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作者 王志涛 李秀梅 王庆伟 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第4期492-495,共4页
A new metal-organic complex Mn1.5(cbba)3(phen)(Hcbba = 2-(4'-chlorine-ben-zoyl)benzoic acid,phen = 1,10-phenanthroline) 1 has been hydrothermally synthesized and struc-turally characterized by single-crystal ... A new metal-organic complex Mn1.5(cbba)3(phen)(Hcbba = 2-(4'-chlorine-ben-zoyl)benzoic acid,phen = 1,10-phenanthroline) 1 has been hydrothermally synthesized and struc-turally characterized by single-crystal X-ray diffraction,elemental analyses,TG and IR spectro-scopy.The compound crystallizes in triclinic,space group P1 with a = 12.137(2),b = 14.535(3),c = 14.894(3),α = 86.380(3),β = 70.381(3),γ = 72.647(3)°,V = 2360.3(8)3,C107H64Cl6Mn3N4O18,Mr = 2071.14,Dc = 1.457 g/cm3,μ(MoKα) = 0.638 mm-1,F(000) = 1055,Z = 1,the final R = 0.0638 and wR = 0.1905 for 6155 observed reflections(I 2σ(I)).It exhibits a 3D supramolecular network through hydrogen bonding and π-π stacking interactions. 展开更多
关键词 hydrothermal synthesis crystal structure manganese(II) complex
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Synthesis, Crystal Structure, Fluorescence, Thermal Stability and Magnetic Properties of the Dinuclear Manganese(Ⅱ) Complex [Mn_2(L)_2(2,2'-bipy)_2(H_2O)_5]_2·3H_2O 被引量:2
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作者 LI Wei LI Chang-Hong +1 位作者 LI Yu-Lin LI Heng-Feng 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第6期973-978,共6页
A new dinuclear manganese complex [Mn2(L)2(2,2'-bipy)2(H2O)512·3H2O has been synthesized with MnSO4·H2O, 2,2'-bibenzoic acid (H2L) and 2,2'-bipyridine(2,2'-bipy) in the mixed solvent ethanol an... A new dinuclear manganese complex [Mn2(L)2(2,2'-bipy)2(H2O)512·3H2O has been synthesized with MnSO4·H2O, 2,2'-bibenzoic acid (H2L) and 2,2'-bipyridine(2,2'-bipy) in the mixed solvent ethanol and water. It crystallizes in monoclinic, space group Pi with a = 9.9944(10), b = 21.939(2), c = 25.628(3) A, a = 108.429(3), β = 100.613(4), 7 = 102.821(3)°, V = 4997.9(9) A3, Dc= 1.355 g/cm^3, Z = 2, F(000) = 2108, GOOF = 1.074, the R= 0.0626 and wR= 0.1531. The structure of the complex contains two [Mn2(L)2(2,2'-bipy)2] units, ten coordinated H2O molecules and three uncoordinated H2O molecules. The fluorescence, thermal stability and magnetic properties of the complex were investigated. 展开更多
关键词 dinuclear manganese complex FLUORESCENCE thermal stability and magnetic properties
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