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Simultaneous immobilization of multiple heavy metal(loid)s in contaminated water and alkaline soil inoculated Fe/Mn oxidizing bacterium 被引量:1
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作者 Yi Wu Shengli Wang +5 位作者 Jun Xu Fei Zang Song Long Yining Wu Yuqing Wang Zhongren Nan 《Journal of Environmental Sciences》 2025年第1期370-381,共12页
Two strains of Fe/Mn oxidizing bacteria tolerant to high concentrations of multiple heavy metal(loid)s and efficient decontamination for them were screened.The surface of the bio-Fe/Mn oxides produced by the oxidation... Two strains of Fe/Mn oxidizing bacteria tolerant to high concentrations of multiple heavy metal(loid)s and efficient decontamination for them were screened.The surface of the bio-Fe/Mn oxides produced by the oxidation of Fe(II)and Mn(II)by Pseudomonas taiwanensis(marked as P4)and Pseudomonas plecoglossicida(marked as G1)contains rich reactive oxygen functional groups,which play critical roles in the removal efficiency and immobilization of heavymetal(loid)s in co-contamination system.The isolated strains P4 and G1 can growwell in the following environments:pH 5-9,NaCl 0-4%,and temperature 20-30℃.The removal efficiencies of Fe,Pb,As,Zn,Cd,Cu,and Mn are effective after inoculation of the strains P4 and G1 in the simulated water system(the initial concentrations of heavy metal(loid)were 1 mg/L),approximately reaching 96%,92%,85%,67%,70%,54%and 15%,respectively.The exchangeable and carbonate bound As,Cd,Pb and Cu are more inclined to convert to the Fe-Mn oxide bound fractions in P4 and G1 treated soil,thereby reducing the phytoavailability and bioaccessible of heavy metal(loid)s.This research provides alternatives method to treat water and soil containing high concentrations of multi-heavy metal(loid)s. 展开更多
关键词 Bio-Fe/Mn oxides PSEUDOMONAS Heavy metal(loid)s Removal and immobilization
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Preparation and Electrochemical Performance of N-doped Carbon Nanospheres Supported Multiple Transition Metal Sulfides Electrocatalyst
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作者 Shuo Yan Zhiqing Ge +4 位作者 Xiangyu Shen Baoying Zhang Shouqun Zhang Mozhen Wang Xuewu Ge 《Chinese Journal of Chemical Physics》 2025年第6期926-938,I0185-I0190,I0240,共20页
The design and preparation of economic and efficient electrolysis water catalysts is an important part in effectively developing and utilizing hydrogen energy.In this work,novel N-doped carbon nanospheres supported mu... The design and preparation of economic and efficient electrolysis water catalysts is an important part in effectively developing and utilizing hydrogen energy.In this work,novel N-doped carbon nanospheres supported multiple transition metal sulfides(NiWCoS/NC)electrocatalysts were prepared by combining the radiation oxidation synthesis and synchronous carbonization-sulfurization.Initially,the precursor material(NiWCoS/OANI,here OANI refers to oligoaniline)containing sulfurand multiple transition metal(Ni,W,and Co)ions loaded on oligoaniline nanospheres was directly one-pot synthesized at room temperature under γ-ray radiation.Subsequently,NiWCoS/NC electrocatalysts were successfully prepared by calcining the NiWCoS/OANI precursor at 800℃.The electrocatalytic performance of NiWCoS/NC for the hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)was characterized by electrochemical analysis methods including linear sweep voltammetry,cyclic voltammetry,chronoamperometry,and electrochemical impedance spectroscopy.The influence of the relative content of the loaded transition metals on the electrocatalytic performance was also investigated.The results indicate that the novel NiWCoS/NC electrocatalyst can significantly reduce the overpotential and Tafel slope for both HER and OER compared to corresponding electrocatalysts with single metal or metal sulfide component.When NiWCoS/NC with a molar ratio of 3:6:10 for W,Co,and S elements was used as electrode material,the overpotentials for HER in 0.5 mol/L H_(2)SO_(4) and OER in 1 mol/L KOH are only 161 mV and 243 mV at a current density of 10 mA/cm^(2),respectively.The Tafel slopes are 74 mV/dec and 88 mV/dec,respectively.The work provides a new direction and method for the design and green facile preparation of high-efficiency overall water splitting catalysts. 展开更多
关键词 multiple transition metal sulfide Radiation oxidation and redox OLIGOANILINE N-doped carbon nanospheres Overall water splitting electrocatalyst
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Recent achievements in rare earth modified metal oxides for environmental and energy applications:A review
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作者 Yicheng Li Qian Liu +2 位作者 Tianhao Li Hao Bi Zhurui Shen 《Chinese Chemical Letters》 2025年第9期112-127,共16页
Rare earth metal elements include lanthanide elements as well as scandium and yttrium,totaling seventeen metal elements.Due to the wide application prospects of rare earth metal elements in various fields such as lumi... Rare earth metal elements include lanthanide elements as well as scandium and yttrium,totaling seventeen metal elements.Due to the wide application prospects of rare earth metal elements in various fields such as luminescent materials,magnetic materials,catalytic materials,electronic devices,they have an important strategic position.In the field of electrocatalysis,rare earth metal elements have great potential for development due to their unique 4f electron layer structure,spin orbit coupling,high reactivity,controllable coordination number,and rich optical properties.However,there is currently a lack of systematic reviews on the modification strategies of rare earth metal elements and the latest developments in electrocatalysis.Therefore,in order to stimulate the enthusiasm of researchers,this review focuses on the application progress of rare earth metal element modified metal oxides in multiple fields such as wastewater treatment,hydrogen peroxide synthesis,hydrogen evolution reaction(HER),carbon dioxide reduction reaction(CO_(2)RR),nitrogen reduction reaction(NRR)and machine learning assisted research.In depth analysis of its electrocatalytic mechanism in various application scenarios and key factors affecting electrocatalytic performance.This review is of great significance for further developing high-performance and multifunctional electrocatalysts,and is expected to provide strong support for the development of energy,environment,and chemical industries. 展开更多
关键词 Rare earth metal ELECTROCATALYSIS metal oxides Machine learning Environment and energy
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Versatile catalytic membranes anchored with metal-nitrogen based metal oxides for ultrafast Fenton-like oxidation
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作者 Qingbai Tian BingLiang Yu +3 位作者 Zhihao Li Wei Hong Qian Li Xing Xu 《Chinese Chemical Letters》 2025年第6期557-561,共5页
Although the powder Fenton-like catalysts have exhibited high catalytic performances towards pollutant degradation,they cannot be directly used for Fenton-like industrialization considering the problems of loss and re... Although the powder Fenton-like catalysts have exhibited high catalytic performances towards pollutant degradation,they cannot be directly used for Fenton-like industrialization considering the problems of loss and recovery.Therefore,the membrane fixation of catalyst is an important step to realize the actual application of Fenton-like catalysts.In this work,an efficient catalyst was developed with Co-N_(x)configuration facilely reconstructed on the surface of Co_(3)O_(4)(Co-N_(x)/Co_(3)O_(4)),which exhibited superior catalytic activity.We further fixed the highly efficient Co-N_(x)/Co_(3)O_(4)onto three kinds of organic membranes and one kind of inorganic ceramic membrane installing with the residual PMS treatment device to investigate its catalytic stability and sustainability.Results indicated that the inorganic ceramic membrane(CM)can achieve high water flux of 710 L m-2h-1,and the similar water flux can be achieved by Co-N_(x)/Co_(3)O_(4)/CM even without the pressure extraction.We also employed the Co-N_(x)/Co_(3)O_(4)/CM system to the wastewater secondary effluent,and the pollutant in complicated secondary effluent could be highly removed by the Co-N_(x)/Co_(3)O_(4)/CM system.This paper provides a new point of view for the application of metal-based catalysts with M-N_(x)coordination in catalytic reaction device. 展开更多
关键词 PEROXYMONOSULFATE Catalytic membranes metal oxides Fenton-like reaction Ceramic membrane
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Level-shifted embedded cluster method may offer a viable alternative for the simulation of metal oxides
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作者 Zi-Jian Zhou Xin-Ping Wu 《Chinese Journal of Structural Chemistry》 2025年第5期1-2,共2页
The use of metal oxides has been extensively documented in the literature and applied in a variety of contexts,including but not limited to energy storage,chemical sensors,and biomedical applications.One of the most s... The use of metal oxides has been extensively documented in the literature and applied in a variety of contexts,including but not limited to energy storage,chemical sensors,and biomedical applications.One of the most significant applications of metal oxides is heterogeneous catalysis,which represents a pivotal technology in industrial production on a global scale.Catalysts serve as the primary enabling agents for chemical reactions,and among the plethora of catalysts,metal oxides including magnesium oxide(MgO),ceria(CeO_(2))and titania(TiO_(2)),have been identified to be particularly effective in catalyzing a variety of reactions[1].Theoretical calculations based on density functional theory(DFT)and a multitude of other quantum chemistry methods have proven invaluable in elucidating the mechanisms of metal-oxide-catalyzed reactions,thereby facilitating the design of high-performance catalysts[2]. 展开更多
关键词 chemical reactionsand industrial production heterogeneous catalysiswhich metal oxides energy storagechemical biomedical applicationsone level shifted embedded cluster method catalystsmetal oxides
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Vibrational Resolved Photoelectron Imaging and Theoretical Study of the Group IVB Transition Metal Oxides Anions:MO_(2)^(-)(M=Ti,Zr,and Hf)
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作者 Hechen Ju Yuan Zhou +4 位作者 Changcai Han Zejie Fei Xiao-Gen Xiong Changwu Dong Hongtao Liu 《Chinese Journal of Chemical Physics》 2025年第5期615-624,I0148,共11页
The vibrational resolved spectra of MO_(2)^(-)/MO_(2)(M=Ti,Zr,and Hf)are reported by using photoelectron imaging and theoretical calculations.The results indicate that all the ground states of anionic and neutral MO_(... The vibrational resolved spectra of MO_(2)^(-)/MO_(2)(M=Ti,Zr,and Hf)are reported by using photoelectron imaging and theoretical calculations.The results indicate that all the ground states of anionic and neutral MO_(2)(M=Ti,Zr,and Hf)compounds are formed in bent insertion structures.The observed ground-state adiabatic detachment energy(ADE)is measured to be 1.597±0.003,1.651±0.003,and 2.119±0.003 eV for TiO_(2)^(-),ZrO_(2)^(-),and HfO_(2)^(-),respectively.The vibrational frequencies of the anionic and neutral MO_(2)are also determined from the experimental spectra.The results of theoretical calculations show that the electronic configurations of MO_(2)^(-)are^(2)A_(1)with C_(2v)point group.Bond order analysis indicates that the two M-O bonds are all multiple characters. 展开更多
关键词 Photoelectron spectroscopy Transition metal oxides Velocity-map imaging Franck-Condon simulation
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Inhibitory Effect of Water on Propane Dehydrogenation over Metal Oxides via Dissociative Adsorption
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作者 Ziyi Li Pengli Yang +4 位作者 Zelin Wu Donglong Fu Zhi-Jian Zhao Sai Chen Chunlei Pei 《Transactions of Tianjin University》 2025年第6期579-589,共11页
Metal oxide catalysts are widely employed in propane dehydrogenation(PDH)for propylene synthesis,requiring sequential reduction-reaction-regeneration cycles.However,the eff ect of water present in the inlet gas or rea... Metal oxide catalysts are widely employed in propane dehydrogenation(PDH)for propylene synthesis,requiring sequential reduction-reaction-regeneration cycles.However,the eff ect of water present in the inlet gas or reactor on the catalytic per-formance of various metal oxides remains insuffi ciently understood.This study examines the infl uence of water on supported metal oxide catalysts,specifi cally CoO x/Al_(2)O_(3),VO x/Al_(2)O_(3),and an industrial analog CrO x/Al_(2)O_(3) catalyst.By combining titration experiments,in situ Fourier transform infrared spectroscopy,kinetic analysis,and isotopic techniques,we demon-strate that even trace amounts of water can markedly suppress PDH performance via dissociative adsorption on the oxide surface.Methanol pretreatment eff ectively scavenges adsorbed water,recovering Lewis acid-base sites and consequently restoring PDH activity.This work underscores the profound inhibitory role of trace water in PDH over metal oxide catalysts and illustrates the potential of methanol pretreatment as an effective strategy to mitigate this limitation. 展开更多
关键词 Propane dehydrogenation metal oxide catalysts Water inhibition Dissociative adsorption Methanol pretreatment
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Designing gadolinium-transition metals-based perovskite type high entropy oxides with good cryogenic magnetocaloric performances
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作者 Junli Lin Xin Wang +2 位作者 Fengying Chen Hai-Feng Li Lingwei Li 《Journal of Materials Science & Technology》 2025年第4期317-323,共7页
Cryogenic magnetic cooling based on the principle of the magnetocaloric effects(MCEs)of magnetic solids has been recognized as an alternative cooling technology due to its significant economic and social benefits.Desi... Cryogenic magnetic cooling based on the principle of the magnetocaloric effects(MCEs)of magnetic solids has been recognized as an alternative cooling technology due to its significant economic and social benefits.Designing novel magnetic materials with good magnetocaloric performance is a prerequisite for practical applications.In this study,three gadolinium-transition metal-based high entropy oxides(HEOs)of Gd(Fe_(1/4)Ni_(1/4)Al_(1/4)Cr_(1/4))O_(3),Gd(Fe_(1/5)Ni_(1/5)Al_(1/5)Cr_(1/5)Co_(1/5))O_(3),and Gd(Fe_(1/6)Ni_(1/6)Al_(1/6)Cr_(1/6)Co_(1/6)Mn_(1/6))O_(3)were designed and systematically characterized regarding their structural and cryogenic magnetic properties.These HEOs were confirmed to crystallize into a single-phase perovskite-type orthorhombic structure with a homogeneous microstructure,reveal a second-order magnetic transition at low temperatures,and exhibit significant cryogenic MCEs.The magnetocaloric performances of the present HEOs,identified by magnetic entropy changes,relative cooling power,and temperature-averaged entropy changes,were com-parable with recently reported candidate materials.The present study indicates potential applications for cryogenic magnetic cooling of the present HEOs and provides meaningful clues for designing and exploring HEOs with good cryogenic magnetocaloric performances. 展开更多
关键词 High entropy oxides Transition metal Magnetocaloric properties Cryogenic magnetic refrigeration
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Correction:Initiating Binary Metal Oxides Microcubes Electromagnetic Wave Absorber Toward Ultrabroad Absorption Bandwidth Through Interfacial and Defects Modulation
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作者 Fushan Li Nannan Wu +8 位作者 Hideo Kimura Yuan Wang Ben Bin Xu Ding Wang Yifan Li Hassan Algadi Zhanhu Guo Wei Du Chuanxin Hou 《Nano-Micro Letters》 2025年第11期530-533,共4页
Following publication of the original article[1],the authors found that they pasted the same data when drawing XRD for sample NCO-1 and NCO-2 in Fig.2a,however,the XRD of all four samples in the manuscript was tested,... Following publication of the original article[1],the authors found that they pasted the same data when drawing XRD for sample NCO-1 and NCO-2 in Fig.2a,however,the XRD of all four samples in the manuscript was tested,and XRD raw data were kept and can be offered.The correct Fig.2 has been provided in this Correction. 展开更多
关键词 binary metal oxides ultrabroad absorption bandwidth electromagnetic wave absorber interfacial modulation defects modulation XRD microcubes
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Screening dual variable-valence metal oxides doped calcium-based material for calcium looping thermochemical energy storage and CO_(2)capture with DFT calculation
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作者 Youhao Zhang Yi Fang +4 位作者 Zhiwei Chu Zirui He Jianli Zhao Kuihua Han Yingjie Li 《Journal of Energy Chemistry》 2025年第8期170-182,共13页
The reaction characteristics of calcium-based materials during calcium looping(CaL)process are pivotal in the efficiency of CaL thermochemical energy storage(TCES)and CO_(2)capture systems.Currently,metal oxide doping... The reaction characteristics of calcium-based materials during calcium looping(CaL)process are pivotal in the efficiency of CaL thermochemical energy storage(TCES)and CO_(2)capture systems.Currently,metal oxide doping is the primary method to enhance the reaction characteristics of calcium-based materials over multiple cycles.In particular,co-doping with variable-valence metal oxides(VVMOs)can effectively increase the oxygen vacancy content in calcium-based materials,significantly improving their cyclic reaction characteristics.However,there are so numerous VVMOs co-doping schemes that the experimental screening process is complex,consuming considerable time and economic costs.Density functional theory(DFT)calculations have been widely used to reveal the impact of metal oxide doping on the cyclic reaction characteristics of calcium-based materials,with calculation results showing good agreement with experimental conclusions.Nevertheless,there is still a lack of research on utilizing DFT to screen calcium-based materials,and a systematic research methodology has not yet been established.In this study,a systematic DFT-based screening methodology for calcium-based materials was proposed.A series of key parameters for DFT calculations including CO_(2)adsorption energy,oxygen vacancy formation energy,and sintering resistance were proposed.Furthermore,a preliminary mathematical model to predict the CaL TCES and CO_(2)capture performance of calcium-based materials was introduced.The aforementioned DFT method was employed to screen for VVMOs co-doped calcium-based materials.The results revealed that Mn and Ce co-doped calcium-based materials exhibited superior DFT-predicted reaction characteristics.These DFT predictions were validated through experimental assessments of cyclic thermochemical energy storage,CO_(2)capture,and relevant characterization.The outcomes demonstrate a high degree of consistency among DFT-based predictions,experimental results,and characterization.Hence,the DFT-based screening methodology for calcium-based materials proposed herein is a viable solution,poised to offer theoretical insights for the efficient design of calcium-based materials. 展开更多
关键词 Density functional theorу Calcium looping Material screening Variable-valence metal oxide CO_(2)capture Thermochemical energy storage
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Spray-dried MOF-derived bimetallic oxide/carbon hybrids with superior electron transfer capability for catalyzing ammonium perchlorate decomposition
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作者 Tianjin Zhi Dongze Li +3 位作者 Yan Li Zhenxin Yi Shunguan Zhu Lin Zhang 《Defence Technology(防务技术)》 2026年第1期224-240,共17页
The thermal decomposition characteristic of ammonium perchlorate(AP)represents a critical factor in determining the performance of solid propellants,which has aroused significant interest on the structure and performa... The thermal decomposition characteristic of ammonium perchlorate(AP)represents a critical factor in determining the performance of solid propellants,which has aroused significant interest on the structure and performance improvement of kinds of catalysts.In this study,bimetallic metal-organic frameworks(MOFs),such as CuCo-BTC(BTC=1,3,5-Benzenetricarboxylic acid,H_(3)BTC),CuNi-BTC,and CoNi-BTC,were synthesized by solvothermal(ST)and spray-drying(SD)methods,and then calcined at 400℃for 2 h to form metal oxides.The catalysts as well as their catalytic effects for AP decomposition were characterized by FTIR,XRD,SEM,XPS,TG,DSC,TG-IR,EIS,CV,and LSV.It was found that the rapid coordination of metal ions with ligands during spray drying may lead to catalytic structural defects,promoting the exposure of reactive active sites and increasing the catalytic active region.The results showed that the addition of 2 wt%binary transition metal oxides(BTMOs)as catalysts significantly reduced the high-temperature decomposition(HTD)temperature of AP and enhanced its heat release.Of particular significance is the observation that SD-CoNiO_(x),prepared by spray-drying,reduced the decomposition temperature of AP from 413.26℃(pure AP)to 306℃and enhanced the heat release from 256.79 J/g(pure AP)to 1496.82 J/g,while concomitantly reducing the activation energy by 42%.By analysing the gaseous products during the decomposition of AP+SD-CoNiO_(x)and AP+ST-CoNiO_(x),it was found that SD-CoNiO_(x)could significantly increase the content of high-valent nitrogen oxides during the AP decomposition reaction,which indicates that the BTMOs prepared by spray-drying in the reaction system are more conducive to accelerating the electron transfer in the thermal decomposition process of AP,and can provide a high concentration of reactive oxygen species that oxidize AP to high-valent nitrogen oxide-containing compounds.The present study shows that the structure selectivity of the spray-drying technique influences surfactant molecular arrangement on catalyst surfaces,resulting in their ability to promote higher electron transfer during the catalytic process.Therefore,BTMOs prepared by spray drying method have higher potential for application. 展开更多
关键词 metal-organic framework derivatives Combustion catalyst Binary transition metal oxides Ammonium perchlorate
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Relationship of Non-Essential and Essential Metals with Vitamin D in a Chinese Early Adolescent Cohort
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作者 Gengfu Wang Weibo Liu +9 位作者 Min Li Ting Tang Qi Zhong Guangbo Qu Yi Zhou Mengyuan Yuan Yonghan Li Fangbiao Tao Puyu Su Chaoxue Zhang 《Biomedical and Environmental Sciences》 2026年第1期116-122,共7页
Vitamin D deficiency(VDD)represents a significant nutritional concern among children and adolescents.The estimated prevalence of VDD in China is 46.8%in this population^([1]).VDD during childhood and adolescence has b... Vitamin D deficiency(VDD)represents a significant nutritional concern among children and adolescents.The estimated prevalence of VDD in China is 46.8%in this population^([1]).VDD during childhood and adolescence has been associated with the onset of various conditions,including acute respiratory infections,asthma,atopic dermatitis,and food allergies^([2]).Multiple factors,including age,sun exposure,adiposity,and genetics,influence vitamin D levels^([2,3]).Increasing attention has been directed toward understanding the environmental determinants that may influence vitamin D status.Given the potential of metallic pollutants to disrupt endocrine function and their ubiquity in the environment,investigating the effects of metal exposure on human vitamin D status,particularly in vulnerable populations,is imperative. 展开更多
关键词 vitamin d deficiency vdd represents Chinese early adolescent cohort essential metals vitamin d non essential metals food allergies multiple acute respiratory infectionsasthmaatopic dermatitisand vitamin D deficiency
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Effect of active metal oxide dopants on wettability and interfacial reaction between K417G superalloy and Al_(2)O_(3)-based ceramic shell
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作者 Bao-hong KOU Wen-tao ZHOU +1 位作者 Yong-hui PENG Jing OUYANG 《Transactions of Nonferrous Metals Society of China》 2026年第1期244-258,共15页
Some active metal oxides(Al_(2)O_(3),TiO_(2),and Cr_(2)O_(3))were selected as dopants to the Al_(2)O_(3)-based ceramic shells for investment casting of K417G superalloy.The effects of dopant types and contents(0,2,5,a... Some active metal oxides(Al_(2)O_(3),TiO_(2),and Cr_(2)O_(3))were selected as dopants to the Al_(2)O_(3)-based ceramic shells for investment casting of K417G superalloy.The effects of dopant types and contents(0,2,5,and 8 wt.%)on the wettability and interfacial reaction between the alloy and shell were investigated by a sessile-drop experiment.The results show that increasing the Al_(2)O_(3) doping contents(0−8 wt.%)reduces the porosity(21.74%−10.08%)and roughness(3.22−1.34μm)of the shell surface.The increase in Cr_(2)O_(3) dopant content(2−8 wt.%)further exacerbates the interfacial reaction,leading to an increase in the thickness of the reaction layer(2.6−3.1μm)and a decrease in the wetting angle(93.9°−91.0°).The addition of Al_(2)O_(3) and TiO_(2) dopants leads to the formation of Al_(2)TiO_(5) composite oxides in the reaction products,which effectively inhibits the interfacial reaction.The increase in TiO_(2) dopant contents(0−8 wt.%)further promotes the formation of Al_(2)TiO_(5),which decreases the thickness of the interfacial reaction layer(3.9−1.2μm)and increases the wetting angle(95.0°−103.8°).The introduced dopants enhance the packing density of the shell surface,while simultaneously suppress the diffusion of active metal elements from the alloy matrix to the interface. 展开更多
关键词 Al_(2)O_(3)-based ceramic shell K417G superalloy metal oxide dopants interfacial reaction WETTABILITY
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Promotional effect of spherical alumina loading with manganese-based bimetallic oxides on nitric-oxide deep oxidation by ozone 被引量:8
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作者 林法伟 王智化 +4 位作者 邵嘉铭 袁定琨 何勇 朱燕群 岑可法 《Chinese Journal of Catalysis》 CSCD 北大核心 2017年第7期1270-1280,共11页
Nitric oxide (NO) deep oxidation to dinitrogen pentoxide (N2O5) by ozone together with wet scrub-bing has become a promising technology for nitrogen-oxide (NOx) removal in industrial boilers. Catalysts wer... Nitric oxide (NO) deep oxidation to dinitrogen pentoxide (N2O5) by ozone together with wet scrub-bing has become a promising technology for nitrogen-oxide (NOx) removal in industrial boilers. Catalysts were introduced to enhance the N2O5 formation rate with less ozone injection and leakage. A series of monometallic catalysts (manganese, cobalt, cerium, iron, copper, and chromium) as pre-pared by the sol-gel method were tested. The manganese oxides achieved an almost 80% conver-sion efficiency at an ozone (O3)/NO molar ratio of 2.0 in 0.12 s. The crystalline structure and porous parameters were determined. The thermodynamic reaction threshold of NO conversion to N2O5 is oxidation with an O3/NO molar ratio of 1.5. Spherical alumina was selected as the support to achieve the threshold, which was believed to improve the catalytic activity by increasing the surface area and the gas-solid contact time. Based on the manganese oxides, cerium, iron, chromium, cop-per, and cobalt were introduced as promoters. Cerium and iron improved the deep-oxidation effi-ciency compared with manganese/spherical alumina, with less than 50 mg/m3 of outlet NO + nitro-gen oxide, and less than 25 mg/m3 of residual ozone at an O3/NO molar ratio of 1.5. The other three metal oxides inhibited catalytic activity. X-ray diffraction, nitrogen adsorption, hydrogen tempera-ture-programmed reduction, and X-ray photoelectron spectroscopy results indicate that the cata-lytic activity is affected by the synergistic action of NOx oxidation and ozone decomposition. 展开更多
关键词 Nitric oxide Deep oxidation Catalyst OZONE Transition metal oxide
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Catalytic evaluation of promoted CeO_2-ZrO_2 by transition, alkali, and alkaline-earth metal oxides for diesel soot oxidation 被引量:11
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作者 Ali Alinezhadchamazketi Abas Ali Khodadadi +1 位作者 Yadollah Mortazavi Ahmad Nemati 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2013年第12期2498-2506,共9页
Series of mixed metal oxides were synthesized by gel-combustion method and their catalytic activities for soot oxidation were investigated. The catalysts were M-Ce-Zr (M = Mn, Cu, Fe, K, Ba, Sr), and χK-20Mn-Ce-Zr... Series of mixed metal oxides were synthesized by gel-combustion method and their catalytic activities for soot oxidation were investigated. The catalysts were M-Ce-Zr (M = Mn, Cu, Fe, K, Ba, Sr), and χK-20Mn-Ce-Zr (χ= 0, 5, 10, 20), they were characterized by XRD, SEM, TPR and BET surface area techniques. The results of soot temperature programmed oxidation (TPO) in an O2 oxidizing atmosphere indicate that K-Ce-Zr has the highest catalytic activity for soot oxidation under loose contact condition, due to enhancement of the soot and catalyst contacts. On the other hand, under a tight contact condition, Mn-Ce-Zr and Cu-Ce-Zr nano-composites have high activities for soot oxidation and lower the soot TPO peak temperatures by about 280 and 270℃, respectively, as compared to non-catalytic soot oxidation. Furthermore, the addition of up to 10 wt.% potassium oxides into Mn-Ce-Zr increases its catalytic activity and further reduces the soot TPO peak temperature by about 40℃ under loose contact condition. 展开更多
关键词 SOOT oxidation DIESEL CERIA-ZIRCONIA metal oxide
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Recent advance on VOCs oxidation over layered double hydroxides derived mixed metal oxides 被引量:12
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作者 Shuangde Li Dongdong Wang +1 位作者 Xiaofeng Wu Yunfa Chen 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第4期550-560,共11页
Catalytic oxidation is regarded as one of the most promising strategies for volatile organic compounds(VOCs)purification.Mixed metal oxides(MMOs),after topological transformation using layered double hydroxides(LDHs)a... Catalytic oxidation is regarded as one of the most promising strategies for volatile organic compounds(VOCs)purification.Mixed metal oxides(MMOs),after topological transformation using layered double hydroxides(LDHs)as precursors,are extensively used as catalysts for VOCs oxidation due to their uniformity advantage.This review summarizes the developments in the LDH-derived VOCs heterogeneous catalytic oxidation over the last 10 years.Particularly,it addresses the VOCs abatement performance over MMO,noble metal/MMO,core-shell structured MMO,and integral MMO film catalysts originating from LDHs.Moreover,it highlights the water vapor effect and oxidation mechanism.This review indicates that LDH-based catalysts are a category of important VOCs oxidation materials. 展开更多
关键词 Volatile organic compounds oxidation Layered double hydroxides Mixed metal oxides Water vapor Oxidation mechanism
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An overview on metal-related catalysts: metal oxides, nanoporous metals and supported metal nanoparticles on metal organic frameworks and zeolites 被引量:9
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作者 Bhupendra Kumar Singh Sunwoo Lee Kyungsu Na 《Rare Metals》 SCIE EI CAS CSCD 2020年第7期751-766,共16页
Metal nanoparticles(NPs) supported on porous materials have shown great advantages in many catalytic application fields. Supported metal NPs are receiving extensive attention due to their significant contribution in a... Metal nanoparticles(NPs) supported on porous materials have shown great advantages in many catalytic application fields. Supported metal NPs are receiving extensive attention due to their significant contribution in a wide range of current and future applications, and this is arguably one of the fastest growing research fields. In this review, we highlight various types of metal catalysts that possess great potential in several catalytic reactions. The major focus has been on metal oxides, nanoporous metals and metal NPs supported on metal-organic frameworks(MOFs) and zeolites. Special attention has been given to the synthesis strategies and application of the NPs supported on MOFs and zeolites, which are considered highly interesting and rapidly expanding areas in heterogeneous catalysis. Finally, the prospects of these catalysts have been included in the concluding remarks. 展开更多
关键词 Supported metal catalysts Porous materials Nanoporous metals Heterogeneous catalysis Zeolites metal oxides metal-organic frameworks
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Rare earth oxides and their supported noble metals in application of environmental catalysis 被引量:17
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作者 Zhiquan Hou Wenbo Pei +5 位作者 Xing Zhang Kunfeng Zhang Yuxi Liu Jiguang Deng Lin Jing Hongxing Dai 《Journal of Rare Earths》 SCIE EI CAS CSCD 2020年第8期819-839,I0001,共22页
Volatile organic compounds(VOCs),methane,carbon monoxide,soot,automotive exhaust,and nitrogen oxides are harmful to the atmosphere and human health.It is urgent to strictly control their emissions.Heterogeneous cataly... Volatile organic compounds(VOCs),methane,carbon monoxide,soot,automotive exhaust,and nitrogen oxides are harmful to the atmosphere and human health.It is urgent to strictly control their emissions.Heterogeneous catalysis is an effective pathway for the removal of these pollutants,and the critical issue is the development of novel and high-performance catalysts.In this review,we briefly summarize the preparation methods,physicochemical properties,catalytic activities,and related reaction mechanisms for the above pollutants removal of the rare earth oxides,mixed rare earth oxide,rare earth oxidesupported noble metal,and mixed rare earth oxide-supported noble metal catalysts that have been investigated by our group and other researchers.It was found that catalytic performance was associated with the factors,such as specific surface area,pore structure,particle size and dispersion,adsorbed oxygen species concentration,reducibility,reactant activation ability or interaction between metal nanoparticles and support.Furthermore,we also envision the development trend of such a topic in future work. 展开更多
关键词 Volatile organic compound Atmospheric pollutant Rare earth oxide Mixed rare earth oxide Supported noble metal catalyst Porous mixed rare earth oxide
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Role of transition metal oxides in g-C_(3)N_(4)-based heterojunctions for photocatalysis and supercapacitors 被引量:11
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作者 Liqi Bai Hongwei Huang +3 位作者 Shixin Yu Deyang Zhang Haitao Huang Yihe Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第1期214-235,I0007,共23页
g-C_(3)N_(4) emerges as a star 2D photocatalyst due to its unique layered structure,suitable band structure and low cost.However,its photocatalytic application is limited by the fast charge recombination and low photo... g-C_(3)N_(4) emerges as a star 2D photocatalyst due to its unique layered structure,suitable band structure and low cost.However,its photocatalytic application is limited by the fast charge recombination and low photoabsorption.Rationally designing g-C_(3)N_(4)-based heterojunction is promising for improving photocatalytic activity.Besides,g-C_(3)N_(4) exhibits great potentials in electrochemical energy storage.In view of the excellent performance of typical transition metal oxides(TMOs)in photocatalysis and energy storage,this review summarized the advances of TMOs/g-C_(3)N_(4) heterojunctions in the above two areas.Firstly,we introduce several typical TMOs based on their crystal structures and band structures.Then,we summarize different kinds of TMOs/g-C_(3)N_(4) heterojunctions,including type Ⅰ/Ⅱ heterojunction,Z-scheme,p-n junction and Schottky junction,with diverse photocatalytic applications(pollutant degradation,water splitting,CO_(2) reduction and N_(2) fixation)and supercapacitive energy storage.Finally,some promising strategies for improving the performance of TMOs/g-C_(3)N_(4) were proposed.Particularly,the exploration of photocatalysis-assisted supercapacitors was discussed. 展开更多
关键词 Transition metal oxides Carbon nitride HETEROJUNCTION PHOTOCATALYSIS SUPERCAPACITORS
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