In the process of using the original key stratum theory to predict the height of a water-flowing fractured zone(WFZ),the influence of rock strata outside the calculation range on the rock strata within the calculation...In the process of using the original key stratum theory to predict the height of a water-flowing fractured zone(WFZ),the influence of rock strata outside the calculation range on the rock strata within the calculation range as well as the fact that the shape of the overburden deformation area will change with the excavation length are ignored.In this paper,an improved key stratum theory(IKS theory)was proposed by fixing these two shortcomings.Then,a WFZ height prediction method based on IKS theory was established and applied.First,the range of overburden involved in the analysis was determined according to the tensile stress distribution range above the goaf.Second,the key stratum in the overburden involved in the analysis was identified through IKS theory.Finally,the tendency of the WFZ to develop upward was determined by judging whether or not the identified key stratum will break.The proposed method was applied and verified in a mining case study,and the reasons for the differences in the development patterns between the WFZs in coalfields in Northwest and East China were also fully explained by this method.展开更多
Perovskite oxides are popular as cathode materials of solid oxide electrolysis cells, because of their good redox stability and high resistance to coke formation.Unexpectedly, a negative effect of Ni doping is found o...Perovskite oxides are popular as cathode materials of solid oxide electrolysis cells, because of their good redox stability and high resistance to coke formation.Unexpectedly, a negative effect of Ni doping is found on Sr2Fe(1.5-x)NixMo(0.5)O(x = 0, 0.05, 0.1, 0.2) cathode for pure CO2 electroreduction at 800 ℃, although Ni is highly active for CO2 electroreduction.The CO2 electroreduction performance degrades with the increase of Ni doping amount.Various characterization techniques are used to disclose the negative effect.Ni doping decreases the perovskite stability under electroreduction conditions, Fe and Ni cations in the B-site are reduced to metal nanoparticles and SrCO3 forms on the surface of the perovskite.The phase instability results from the weaker Ni–O bond.Although the Fe-Ni nanoparticles are in favor of the CO2 electroreduction, too much SrCO3 and carbon deposition block the charge transfer and diffusion of oxygenous species on the cathode surface.展开更多
The preparation of natural brucite nanofibers through dispersion by the wet process is described. The test results indicate that brucite fibers can be well dispersed by using sodium dioctyl sulfosuccinate (OT) as th...The preparation of natural brucite nanofibers through dispersion by the wet process is described. The test results indicate that brucite fibers can be well dispersed by using sodium dioctyl sulfosuccinate (OT) as the dispersant at a dispersant/fiber mass ratio of 0.15:1, dispersing for 30 min at a water/solid mass ratio of 20:1. The prepared nanofibers were characterized with X-ray diffraction (XRD), scanning electron microscope (SEM), and transmission electron microscope (TEM). It is shown that the prepared single brucite nanofiber is around 30 nm in diameter and the talus of the nonsingle brucite nanofibers is about 50-150 nm in diameter. Natural brucite mineral fibers were treated by the dispersion method to obtain nanomaterials. These fibers have significant advantages over artificial nanofibers both in yield and in cost.展开更多
The adverse effects of global warming and climate change have driven the exploration of feasible routes for CO_(2) capture,storage,conversion and utilization.The processes related to CO_(2) conversion in high-temperat...The adverse effects of global warming and climate change have driven the exploration of feasible routes for CO_(2) capture,storage,conversion and utilization.The processes related to CO_(2) conversion in high-temperature electrochemical devices(HTEDs)using dense ceramic membranes are particularly appealing due to the simultaneous realization of highly efficient CO_(2) conversion and value-added chemical production as well as the generation of electricity and storage of renewable energy in some cases.Currently,most studies are focused on the two processes,CO_(2) electrolysis and H2O/CO_(2) co-electrolysis in oxygen-conducting solid oxide electrolysis cell(O-SOEC)reactors.Less attention has been paid to other meaningful CO_(2)-conversion-related processes in HTEDs and systematic summary and analysis are currently not available.This review will fill the gap and classify the CO_(2)-conversion-related processes in HTEDs reported in recent years into four types accord-ing to the related reactions,including assisted CO_(2) reduction to CO,H2O and CO_(2) co-conversion,dry reforming of methane and CO_(2) hydrogenation.Firstly,an overview of the fundamentals of HTED processes is presented,and then the related mechanism and research progress of each type of reactions in different HTEDs are elucidated and concluded accordingly.The remaining major technical issues are also briefly introduced.Lastly,the main challenges and feasible solutions as well as the future prospects of HTEDs for CO_(2)-conversion-related processes are also discussed in this review.展开更多
Correction to:Electrochemical Energy Reviews https://doi.org/10.1007/s41918-021-00099-2 The original version of this article unfortunately contained a mistake.The graphical abstract was missing.The original article ha...Correction to:Electrochemical Energy Reviews https://doi.org/10.1007/s41918-021-00099-2 The original version of this article unfortunately contained a mistake.The graphical abstract was missing.The original article has been corrected.展开更多
基金The study was jointly supported by the State Key Program of National Natural Science Foundation of China (Grant No. 41430643) and the National Key Basic Research Program of China (973 Program) (Grant No. 2015CB251601).
基金supported by the Key Projects of Natural Science Foundation of China(No.41931284)the Scientific Research Start-Up Fund for High-Level Introduced Talents of Anhui University of Science and Technology(No.2022yjrc21).
文摘In the process of using the original key stratum theory to predict the height of a water-flowing fractured zone(WFZ),the influence of rock strata outside the calculation range on the rock strata within the calculation range as well as the fact that the shape of the overburden deformation area will change with the excavation length are ignored.In this paper,an improved key stratum theory(IKS theory)was proposed by fixing these two shortcomings.Then,a WFZ height prediction method based on IKS theory was established and applied.First,the range of overburden involved in the analysis was determined according to the tensile stress distribution range above the goaf.Second,the key stratum in the overburden involved in the analysis was identified through IKS theory.Finally,the tendency of the WFZ to develop upward was determined by judging whether or not the identified key stratum will break.The proposed method was applied and verified in a mining case study,and the reasons for the differences in the development patterns between the WFZs in coalfields in Northwest and East China were also fully explained by this method.
基金the financial support from the National Natural Science Foundation of China (91545202, U1508203)the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No.XDB17000000)+2 种基金Dalian National Laboratory for Clean Energy (DNL)CAS (DICP&QIBEBT UN201708)Dalian Youth Science and Technology Fund (2017RQ064)
文摘Perovskite oxides are popular as cathode materials of solid oxide electrolysis cells, because of their good redox stability and high resistance to coke formation.Unexpectedly, a negative effect of Ni doping is found on Sr2Fe(1.5-x)NixMo(0.5)O(x = 0, 0.05, 0.1, 0.2) cathode for pure CO2 electroreduction at 800 ℃, although Ni is highly active for CO2 electroreduction.The CO2 electroreduction performance degrades with the increase of Ni doping amount.Various characterization techniques are used to disclose the negative effect.Ni doping decreases the perovskite stability under electroreduction conditions, Fe and Ni cations in the B-site are reduced to metal nanoparticles and SrCO3 forms on the surface of the perovskite.The phase instability results from the weaker Ni–O bond.Although the Fe-Ni nanoparticles are in favor of the CO2 electroreduction, too much SrCO3 and carbon deposition block the charge transfer and diffusion of oxygenous species on the cathode surface.
基金This study was financially supported by the National High-Tech Research and Development Program of China (No.2003AA302610)
文摘The preparation of natural brucite nanofibers through dispersion by the wet process is described. The test results indicate that brucite fibers can be well dispersed by using sodium dioctyl sulfosuccinate (OT) as the dispersant at a dispersant/fiber mass ratio of 0.15:1, dispersing for 30 min at a water/solid mass ratio of 20:1. The prepared nanofibers were characterized with X-ray diffraction (XRD), scanning electron microscope (SEM), and transmission electron microscope (TEM). It is shown that the prepared single brucite nanofiber is around 30 nm in diameter and the talus of the nonsingle brucite nanofibers is about 50-150 nm in diameter. Natural brucite mineral fibers were treated by the dispersion method to obtain nanomaterials. These fibers have significant advantages over artificial nanofibers both in yield and in cost.
基金supported by the Natural Sciences and Engineering Research Council of Canada,the Discovery Grant(GRPIN-2016-05494)the Alberta Innovates Technology Futures Research Grant.
文摘The adverse effects of global warming and climate change have driven the exploration of feasible routes for CO_(2) capture,storage,conversion and utilization.The processes related to CO_(2) conversion in high-temperature electrochemical devices(HTEDs)using dense ceramic membranes are particularly appealing due to the simultaneous realization of highly efficient CO_(2) conversion and value-added chemical production as well as the generation of electricity and storage of renewable energy in some cases.Currently,most studies are focused on the two processes,CO_(2) electrolysis and H2O/CO_(2) co-electrolysis in oxygen-conducting solid oxide electrolysis cell(O-SOEC)reactors.Less attention has been paid to other meaningful CO_(2)-conversion-related processes in HTEDs and systematic summary and analysis are currently not available.This review will fill the gap and classify the CO_(2)-conversion-related processes in HTEDs reported in recent years into four types accord-ing to the related reactions,including assisted CO_(2) reduction to CO,H2O and CO_(2) co-conversion,dry reforming of methane and CO_(2) hydrogenation.Firstly,an overview of the fundamentals of HTED processes is presented,and then the related mechanism and research progress of each type of reactions in different HTEDs are elucidated and concluded accordingly.The remaining major technical issues are also briefly introduced.Lastly,the main challenges and feasible solutions as well as the future prospects of HTEDs for CO_(2)-conversion-related processes are also discussed in this review.
文摘Correction to:Electrochemical Energy Reviews https://doi.org/10.1007/s41918-021-00099-2 The original version of this article unfortunately contained a mistake.The graphical abstract was missing.The original article has been corrected.