Transition metal carbonates(TMCs)hold great potential as high-performance electrodes for alkali metal-ion batteries,owing to multiple-ion storage mechanisms involving conversion process and electrocatalytic reaction.H...Transition metal carbonates(TMCs)hold great potential as high-performance electrodes for alkali metal-ion batteries,owing to multiple-ion storage mechanisms involving conversion process and electrocatalytic reaction.However,they still suffer from inferior electronic conductivity and volume variation during delithiation/lithiation.Heterostructure and heteroatoms doping offer immense promise in enhancing reaction kinetics and structural integrity,which unfortunately have not been achieved in TMCs.Herein,a unique TMCs heterostructure with Ni-doped MnCO_(3)as“core”and Mn-doped NiCO_(3)as“shell”,which is wrapped by graphene(NM@MN/RGO),is achieved by cations differentiation strategy.The formation process for core-shell NM@MN consists of epitaxial growth of NiCO_(3)from MnCO_(3)and synchronously mutual doping,owing to the similar crystal structures but different solubility product constant/formation energy of MnCO_(3)and NiCO_(3).In-situ electrochemical impedance spectroscopy,galvanostatic intermittent titration technique,differential capacity versus voltage plots,theoretical calculation and kinetic analysis reveal the superior electrochemical activity of the NM@MN/RGO to MnCO_(3)/RGO.The NM@MN/RGO shows excellent lithium storage properties(1013.4 mAh·g^(-1)at 0.1 A·g^(-1)and 760 mAh·g^(-1)after 1000 cycles at 2 A·g^(-1))and potassium storage properties(capacity decay rate of 0.114 mAh·g^(-1)per cycle).This work proposes an efficient cation differentiation strategy for constructing advanced TMC electrodes.展开更多
Carbonates present complex pore systems that strongly influence the physical properties and their interrelationships.This study proposes a new approach to establish pore-type mixing-based permeability transforms by in...Carbonates present complex pore systems that strongly influence the physical properties and their interrelationships.This study proposes a new approach to establish pore-type mixing-based permeability transforms by integrating well-log and core data.We investigate the influence of pore-structure heterogeneity on permeability and velocity through the rock-frame flexibility factors(γ and γ_(μ)),derivable using standard sonic and density logs.We derive permeability transforms,with correlation coefficients,R of 0.8 to 0.9,from core measurements and pore-structure variations-dependent physical parameters,namely the porosity exponent(m),Poisson’s ratio(σ),velocity deviation log(VDL),and velocity ratio(VR).Through extrapolation using log-data,the m-and VDL-based correlations provide significantly better permeability estimates,with the highest accuracy attained with the m-based correlation,whereas the VR-andσ-based correlations lead to permeability overes-timation for high porosities.We plotted log-derived porosity vs.permeability,obtained applying the m-based correlation,to generate consistent porosity-permeability relationships,which account for pore-structure heterogeneity,by sorting the scattering points into distinct groups/trends by considering the variations of pore-structure types and abundance of a specific porosity.For the studied oilfield,three porosity-permeability relationships are identified,with correlation coefficients approaching 0.9,thus validating the approach and supporting its application in petrophysically similar reservoirs.展开更多
The present levels of CO_(2)emission in the atmosphere require the development of technologies to achieve carbon neutrality using inexpensive processes.Conversion of CO_(2)into cyclic carbonates is one of the solution...The present levels of CO_(2)emission in the atmosphere require the development of technologies to achieve carbon neutrality using inexpensive processes.Conversion of CO_(2)into cyclic carbonates is one of the solutions to this problem.Here,we synthesized a ZnV_(2)O_(6)/Bi_(2)WO_(6)nanocomposite and catalyzed the cycloaddition of CO_(2)to epoxides for the green synthesis of cyclic carbonates under visible light irradiation.The present nanocomposite photocatalyst exhibited up to 96%yield of cyclic carbonates.The photocatalyst was found to be efficient for photocatalytic cycloaddition reactions,and the recovered photocatalyst showed stability in up to five consecutive photocatalytic experiments.The current methodology of cyclic carbonate production is a significant step toward the mitigation of atmospheric CO_(2)and can work well with the development of nanocomposite photocatalysts.展开更多
In the context of peaking carbon dioxide emissions and carbon neutrality,development of feasible methods for converting CO_(2)into high value-added chemicals stands out as a hot subject.In this study,P[D+COO^(−)][Br^(...In the context of peaking carbon dioxide emissions and carbon neutrality,development of feasible methods for converting CO_(2)into high value-added chemicals stands out as a hot subject.In this study,P[D+COO^(−)][Br^(−)][DBUH^(+)],a series of novel heterogeneous dual-ionic poly(ionic liquid)s(PILs)were synthesized readily from 2-(dimethylamino)ethyl methacrylate(DMAEMA),bromo-substituted aliphatic acids,organic bases and divinylbenzene(DVB).The structures,compositions and morphologies were characterized or determined by nuclear magnetic resonance(NMR),thermal gravimetric analysis(TGA),infrared spectroscopy(IR),scanning electron microscopes(SEM),and Brunauer-Emmett-Teller analysis(BET),etc.Application of the P[D+COO^(−)][Br^(−)][DBUH^(+)]series as catalysts in converting CO_(2)into cyclic carbonates showed that P[D+COO^(−)][Br^(−)][DBUH^(+)]-2/1/0.6was able to catalyze epiclorohydrin-CO_(2)cycloaddition the most efficiently.This afforded chloropropylene carbonate(CPC)in 98.4%yield with≥99%selectivity in 24 hr under solvent-and additive-free conditions at atmospheric pressure.Reusability experiments showed that recycling of the catalyst 6 times only resulted in a slight decline in the catalytic performance.In addition,it could be used for the synthesis of a variety of differently substituted cyclic carbonates in good to excellent yields.Finally,key catalytic active sites were probed,and a reasonable mechanism was proposed accordingly.In summary,this work poses an efficient strategy for heterogenization of dual-ionic PILs and provides amild and environmentally benign approach to the fixation and utilization of carbon dioxide.展开更多
Many new and developed oilfields are confined to carbonate reservoirs with a complex void space structure.In this study,the behavior of carbonates as a function of decreased reservoir pressure was examined.The study w...Many new and developed oilfields are confined to carbonate reservoirs with a complex void space structure.In this study,the behavior of carbonates as a function of decreased reservoir pressure was examined.The study was based on actual production data from wells rather than just on model data or results from computational experiments.Well-test data(170 well tests)and laboratory core samples(45 samples)results were used in the analysis.The problem of reservoir deformation has been compre-hensively addressed at the micro and macro levels.The effect of reservoir permeability throughout the entire reservoir volume on reservoir pressure was determined.With a decline in reservoir pressure,the permeability of fractures and pores in carbonates decreases.The deformation coefficients,which char-acterize the actual rate of decrease in permeability with decreasing reservoir pressure,were also calculated.The deformation coefficients and data from core studies using μ-CT and SEM were compared.Based on micro-CT data,the effective diameters of the voids were calculated to be 93μm,109μm,and 140μm for the Vinnikovskoe,Sofinskoe,and Sukharev fields,respectively.Based on μ-CT and SEM data,the predominant geometric shapes of the voids were assessed.The deformation coefficient of voids was found to depend on their size and geometric shape.The study's findings revealed deformation co-efficients of 0.172,0.205,and 0.748 for the Vinnikovskoe,Sofinskoe,and Sukharev fields,respectively.Maximum deformation coefficients are typical for large voids with a predominant slot-like shape.However,even with the predominance of primary spherical voids in carbonates,the permeability of voids decreases with decreasing reservoir pressure.展开更多
Marine carbonates,the major carrier of carbon upon the upper crust,can be subducted into the Earth’s interior along with oceanic crust,and then returned to the surface through magmatism,which constitute the deep carb...Marine carbonates,the major carrier of carbon upon the upper crust,can be subducted into the Earth’s interior along with oceanic crust,and then returned to the surface through magmatism,which constitute the deep carbon cycle.This process plays an important role in modulating the CO_(2) concentrations in the atmosphere over geologic time,and thus the forming of the habitable earth.Therefore,identifying recycled marine carbonates in the mantle is critical to well understand the global deep carbon cycle.Calcium is one of the major constituent cations in marine carbonates and its isotopes may be a potential tracer for recycled marine carbonates in the mantle.To further evaluate the capability and challenges of Ca isotopes as such a geochemical tracer,we reviewed the Ca isotopic compositions in important reservoirs and the behavior of Ca isotopes during high-temperature geological processes that are related to the deep carbon cycle,including plate subduction,mantle metasomatism,mantle partial melting,magma differentiation,etc.Available studies show that carbonate-rich marine sediments have significantly lowerδ^(44/40) Ca than the Earth mantle,and metasomatism by such recycled materials can cause lighter Ca isotopic compositions in deep mantle-derived rocks than those of the depleted mantle and mid ocean ridge basalts.However,the Ca isotopic fractionation during partial melting of mantle peridotites is small(~0.10‰)and the Ca isotopic fractionation during plate subduction and intermediate-mafic magma evolution is indistinguishable.These investigations suggest that Ca isotopes have great advances in tracing such recycled materials in the mantle.However,other processes(such as the influence by partial melts of eclogites)may induce similar effects on mantle-derived rocks as subducted marine carbonates but still remains debated,and thus further investigations are strongly needed in the future.展开更多
The aim of ＂green chemistry＂ and ＂atom economy＂ is to utilize carbon dioxide and replace harmful reactants such as CO and phosgene for the production of cyclic carbonates. In this paper, metal-free catalysts inclu...The aim of ＂green chemistry＂ and ＂atom economy＂ is to utilize carbon dioxide and replace harmful reactants such as CO and phosgene for the production of cyclic carbonates. In this paper, metal-free catalysts including organic bases, ionic liquids, supported catalysts, organic copolymers and carbon materials for the synthesis of cyclic carbonates by the cycloaddition of carbon dioxide to epoxides are reviewed. Recent advances in the design of the catalysts and the understanding of the reaction mechanism are summarized and discussed. The synergistic effects of organic bases and hydrogen bond donors, organic bases and nucleophilic anions, hydrogen bond donors and nucleophilic anions and active components and supports are highlighted. The challenge is to develop metal-free catalysts suitable for carbon dioxide capture and fixation. The ultimate goal is to synthesize cyclic carbonates in a flow reactor directly using carbon dioxide from industrial flue gas at ambient temperature and atmospheric pressure. By using synergetic effects, a multi-functional approach can meet the design strategy of metal-free catalysts for carbon dioxide adsorption and activation as well as epoxide ring opening.展开更多
The Ordovician carbonate rocks of the Yingshan formation in the Tarim Basin have a complex pore structure owing to diagenetic and secondary structures. Seismic elastic parameters（e.g., wave velocity） depend on poros...The Ordovician carbonate rocks of the Yingshan formation in the Tarim Basin have a complex pore structure owing to diagenetic and secondary structures. Seismic elastic parameters（e.g., wave velocity） depend on porosity and pore structure. We estimated the average specific surface, average pore-throat radius, pore roundness, and average aspect ratio of carbonate rocks from the Tazhong area. High P-wave velocity samples have small average specific surface, small average pore-throat radius, and large average aspect ratio. Differences in the pore structure of dense carbonate samples lead to fluid-related velocity variability. However, the relation between velocity dispersion and average specific surface, or the average aspect ratio, is not linear. For large or small average specific surface, the pore structure of the rock samples becomes uniform, which weakens squirt fl ow and minimizes the residuals of ultrasonic data and predictions with the Gassmann equation. When rigid dissolved（casting mold） pores coexist with less rigid microcracks, there are significant P-wave velocity differences between measurements and predictions.展开更多
Using 1-butyl-3-methyl-imidazolium bromide （BM1MBr） as the supporting electrolyte and magne- sium as the sacrificial anode, a new and highly efficient electrochemically catalytic route was devel- oped for the synthe...Using 1-butyl-3-methyl-imidazolium bromide （BM1MBr） as the supporting electrolyte and magne- sium as the sacrificial anode, a new and highly efficient electrochemically catalytic route was devel- oped for the synthesis of cyclic carbonates from epoxides and CO2. Based on the cooperative action of BMIMBr and an electrogenerated magnesium salt obtained under a N2 atmosphere, CO2 reacted with a wide range of epoxides to readily generate cyclic carbonates in moderate to excellent yields under mild conditions.展开更多
基金supported by the National Natural Science Foundation of China(NSFC)(Nos.52202371 and 51902102)the Natural Science Foundation of Shandong Province(Nos.ZR202211230173,ZR2020QE066 and ZR2021QE200)+2 种基金the Opening Project of State Key Laboratory of Advanced Technology for Float Glass(No.2020KF08)the SDUT&Zibo City Integration Development Project(No.2021SNPT0045)the fellowship of China Postdoctoral Science Foundation(No.2020M672081).
文摘Transition metal carbonates(TMCs)hold great potential as high-performance electrodes for alkali metal-ion batteries,owing to multiple-ion storage mechanisms involving conversion process and electrocatalytic reaction.However,they still suffer from inferior electronic conductivity and volume variation during delithiation/lithiation.Heterostructure and heteroatoms doping offer immense promise in enhancing reaction kinetics and structural integrity,which unfortunately have not been achieved in TMCs.Herein,a unique TMCs heterostructure with Ni-doped MnCO_(3)as“core”and Mn-doped NiCO_(3)as“shell”,which is wrapped by graphene(NM@MN/RGO),is achieved by cations differentiation strategy.The formation process for core-shell NM@MN consists of epitaxial growth of NiCO_(3)from MnCO_(3)and synchronously mutual doping,owing to the similar crystal structures but different solubility product constant/formation energy of MnCO_(3)and NiCO_(3).In-situ electrochemical impedance spectroscopy,galvanostatic intermittent titration technique,differential capacity versus voltage plots,theoretical calculation and kinetic analysis reveal the superior electrochemical activity of the NM@MN/RGO to MnCO_(3)/RGO.The NM@MN/RGO shows excellent lithium storage properties(1013.4 mAh·g^(-1)at 0.1 A·g^(-1)and 760 mAh·g^(-1)after 1000 cycles at 2 A·g^(-1))and potassium storage properties(capacity decay rate of 0.114 mAh·g^(-1)per cycle).This work proposes an efficient cation differentiation strategy for constructing advanced TMC electrodes.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA14010302)the National Key Research and Development Program of China(No.2017YFC0603104)the Ministère de l’Enseignement Supérieur et de la Recherche,Agence Nigérienne des Allocations et des Bourses,ANAB-Niger(No.2015563007).
文摘Carbonates present complex pore systems that strongly influence the physical properties and their interrelationships.This study proposes a new approach to establish pore-type mixing-based permeability transforms by integrating well-log and core data.We investigate the influence of pore-structure heterogeneity on permeability and velocity through the rock-frame flexibility factors(γ and γ_(μ)),derivable using standard sonic and density logs.We derive permeability transforms,with correlation coefficients,R of 0.8 to 0.9,from core measurements and pore-structure variations-dependent physical parameters,namely the porosity exponent(m),Poisson’s ratio(σ),velocity deviation log(VDL),and velocity ratio(VR).Through extrapolation using log-data,the m-and VDL-based correlations provide significantly better permeability estimates,with the highest accuracy attained with the m-based correlation,whereas the VR-andσ-based correlations lead to permeability overes-timation for high porosities.We plotted log-derived porosity vs.permeability,obtained applying the m-based correlation,to generate consistent porosity-permeability relationships,which account for pore-structure heterogeneity,by sorting the scattering points into distinct groups/trends by considering the variations of pore-structure types and abundance of a specific porosity.For the studied oilfield,three porosity-permeability relationships are identified,with correlation coefficients approaching 0.9,thus validating the approach and supporting its application in petrophysically similar reservoirs.
基金sponsored in part by the National Natural Science Foundation of China(No.21477167)the Science and Technology Research Plan Program of Henan Province(Nos.222102320328,232102210075,232102320137)the Key Science Research Program Foundation of High Education Schools of Henan Province(No.23B610010).
文摘The present levels of CO_(2)emission in the atmosphere require the development of technologies to achieve carbon neutrality using inexpensive processes.Conversion of CO_(2)into cyclic carbonates is one of the solutions to this problem.Here,we synthesized a ZnV_(2)O_(6)/Bi_(2)WO_(6)nanocomposite and catalyzed the cycloaddition of CO_(2)to epoxides for the green synthesis of cyclic carbonates under visible light irradiation.The present nanocomposite photocatalyst exhibited up to 96%yield of cyclic carbonates.The photocatalyst was found to be efficient for photocatalytic cycloaddition reactions,and the recovered photocatalyst showed stability in up to five consecutive photocatalytic experiments.The current methodology of cyclic carbonate production is a significant step toward the mitigation of atmospheric CO_(2)and can work well with the development of nanocomposite photocatalysts.
基金supported by the Applied Basic Research Foundation of Guangdong Province(No.2019A1515110551)the Science Foundation for Distinguished Scholars of Dongguan University of Technology(No.196100041051).
文摘In the context of peaking carbon dioxide emissions and carbon neutrality,development of feasible methods for converting CO_(2)into high value-added chemicals stands out as a hot subject.In this study,P[D+COO^(−)][Br^(−)][DBUH^(+)],a series of novel heterogeneous dual-ionic poly(ionic liquid)s(PILs)were synthesized readily from 2-(dimethylamino)ethyl methacrylate(DMAEMA),bromo-substituted aliphatic acids,organic bases and divinylbenzene(DVB).The structures,compositions and morphologies were characterized or determined by nuclear magnetic resonance(NMR),thermal gravimetric analysis(TGA),infrared spectroscopy(IR),scanning electron microscopes(SEM),and Brunauer-Emmett-Teller analysis(BET),etc.Application of the P[D+COO^(−)][Br^(−)][DBUH^(+)]series as catalysts in converting CO_(2)into cyclic carbonates showed that P[D+COO^(−)][Br^(−)][DBUH^(+)]-2/1/0.6was able to catalyze epiclorohydrin-CO_(2)cycloaddition the most efficiently.This afforded chloropropylene carbonate(CPC)in 98.4%yield with≥99%selectivity in 24 hr under solvent-and additive-free conditions at atmospheric pressure.Reusability experiments showed that recycling of the catalyst 6 times only resulted in a slight decline in the catalytic performance.In addition,it could be used for the synthesis of a variety of differently substituted cyclic carbonates in good to excellent yields.Finally,key catalytic active sites were probed,and a reasonable mechanism was proposed accordingly.In summary,this work poses an efficient strategy for heterogenization of dual-ionic PILs and provides amild and environmentally benign approach to the fixation and utilization of carbon dioxide.
基金funded by the Ministry of Science and Higher Education of the Russian Federation(Project No.FSNM-2023-0005).
文摘Many new and developed oilfields are confined to carbonate reservoirs with a complex void space structure.In this study,the behavior of carbonates as a function of decreased reservoir pressure was examined.The study was based on actual production data from wells rather than just on model data or results from computational experiments.Well-test data(170 well tests)and laboratory core samples(45 samples)results were used in the analysis.The problem of reservoir deformation has been compre-hensively addressed at the micro and macro levels.The effect of reservoir permeability throughout the entire reservoir volume on reservoir pressure was determined.With a decline in reservoir pressure,the permeability of fractures and pores in carbonates decreases.The deformation coefficients,which char-acterize the actual rate of decrease in permeability with decreasing reservoir pressure,were also calculated.The deformation coefficients and data from core studies using μ-CT and SEM were compared.Based on micro-CT data,the effective diameters of the voids were calculated to be 93μm,109μm,and 140μm for the Vinnikovskoe,Sofinskoe,and Sukharev fields,respectively.Based on μ-CT and SEM data,the predominant geometric shapes of the voids were assessed.The deformation coefficient of voids was found to depend on their size and geometric shape.The study's findings revealed deformation co-efficients of 0.172,0.205,and 0.748 for the Vinnikovskoe,Sofinskoe,and Sukharev fields,respectively.Maximum deformation coefficients are typical for large voids with a predominant slot-like shape.However,even with the predominance of primary spherical voids in carbonates,the permeability of voids decreases with decreasing reservoir pressure.
基金Supported by the National Natural Science Foundation of China(Nos.42322302,42373048)the Youth Innovation Promotion Association,Chinese Academy of Sciences(No.2022207)+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB42020303)the Laoshan Laboratory(No.LSKJ202204100)。
文摘Marine carbonates,the major carrier of carbon upon the upper crust,can be subducted into the Earth’s interior along with oceanic crust,and then returned to the surface through magmatism,which constitute the deep carbon cycle.This process plays an important role in modulating the CO_(2) concentrations in the atmosphere over geologic time,and thus the forming of the habitable earth.Therefore,identifying recycled marine carbonates in the mantle is critical to well understand the global deep carbon cycle.Calcium is one of the major constituent cations in marine carbonates and its isotopes may be a potential tracer for recycled marine carbonates in the mantle.To further evaluate the capability and challenges of Ca isotopes as such a geochemical tracer,we reviewed the Ca isotopic compositions in important reservoirs and the behavior of Ca isotopes during high-temperature geological processes that are related to the deep carbon cycle,including plate subduction,mantle metasomatism,mantle partial melting,magma differentiation,etc.Available studies show that carbonate-rich marine sediments have significantly lowerδ^(44/40) Ca than the Earth mantle,and metasomatism by such recycled materials can cause lighter Ca isotopic compositions in deep mantle-derived rocks than those of the depleted mantle and mid ocean ridge basalts.However,the Ca isotopic fractionation during partial melting of mantle peridotites is small(~0.10‰)and the Ca isotopic fractionation during plate subduction and intermediate-mafic magma evolution is indistinguishable.These investigations suggest that Ca isotopes have great advances in tracing such recycled materials in the mantle.However,other processes(such as the influence by partial melts of eclogites)may induce similar effects on mantle-derived rocks as subducted marine carbonates but still remains debated,and thus further investigations are strongly needed in the future.
基金supported by the National Science and Technology Support Project of China(2013BAC11B03)the National Natural Science Foundation of China(21401054,21476065,21273067)the Graduate Student Scientific Research Innovation Fund Project of Hunan Province(CX2015B082)~~
文摘The aim of ＂green chemistry＂ and ＂atom economy＂ is to utilize carbon dioxide and replace harmful reactants such as CO and phosgene for the production of cyclic carbonates. In this paper, metal-free catalysts including organic bases, ionic liquids, supported catalysts, organic copolymers and carbon materials for the synthesis of cyclic carbonates by the cycloaddition of carbon dioxide to epoxides are reviewed. Recent advances in the design of the catalysts and the understanding of the reaction mechanism are summarized and discussed. The synergistic effects of organic bases and hydrogen bond donors, organic bases and nucleophilic anions, hydrogen bond donors and nucleophilic anions and active components and supports are highlighted. The challenge is to develop metal-free catalysts suitable for carbon dioxide capture and fixation. The ultimate goal is to synthesize cyclic carbonates in a flow reactor directly using carbon dioxide from industrial flue gas at ambient temperature and atmospheric pressure. By using synergetic effects, a multi-functional approach can meet the design strategy of metal-free catalysts for carbon dioxide adsorption and activation as well as epoxide ring opening.
基金supported by the Natural Science Foundation of China(No.41274138)
文摘The Ordovician carbonate rocks of the Yingshan formation in the Tarim Basin have a complex pore structure owing to diagenetic and secondary structures. Seismic elastic parameters（e.g., wave velocity） depend on porosity and pore structure. We estimated the average specific surface, average pore-throat radius, pore roundness, and average aspect ratio of carbonate rocks from the Tazhong area. High P-wave velocity samples have small average specific surface, small average pore-throat radius, and large average aspect ratio. Differences in the pore structure of dense carbonate samples lead to fluid-related velocity variability. However, the relation between velocity dispersion and average specific surface, or the average aspect ratio, is not linear. For large or small average specific surface, the pore structure of the rock samples becomes uniform, which weakens squirt fl ow and minimizes the residuals of ultrasonic data and predictions with the Gassmann equation. When rigid dissolved（casting mold） pores coexist with less rigid microcracks, there are significant P-wave velocity differences between measurements and predictions.
基金supported by the National Natural Science Foundation of China(21303053)the Open Project of State Key Laboratory of Chemical Engineering(SKLChE-14C02)~~
文摘Using 1-butyl-3-methyl-imidazolium bromide （BM1MBr） as the supporting electrolyte and magne- sium as the sacrificial anode, a new and highly efficient electrochemically catalytic route was devel- oped for the synthesis of cyclic carbonates from epoxides and CO2. Based on the cooperative action of BMIMBr and an electrogenerated magnesium salt obtained under a N2 atmosphere, CO2 reacted with a wide range of epoxides to readily generate cyclic carbonates in moderate to excellent yields under mild conditions.
