The increasing atmospheric carbon dioxide (CO_(2)) concentration has exposed a series of crises in the earth's ecological environment.How to effectively fix and convert carbon dioxide into products with added valu...The increasing atmospheric carbon dioxide (CO_(2)) concentration has exposed a series of crises in the earth's ecological environment.How to effectively fix and convert carbon dioxide into products with added value has attracted the attention of many researchers.Cell-free enzyme catalytic system coupled with electrical and light have been a promising attempt in the field of biological carbon fixation in recent years.In this review,the research progresses of photoenzyme catalysis,electroenzyme catalysis and photo-electroenzyme catalysis for converting carbon dioxide into chemical products in cell-free systems are systematically summarized.We focus on reviewing and comparing various coupling methods and principles of photoenzyme catalysis and electroenzyme catalysis in cell-free systems,especially the materials used in the construction of the coupling system,and analyze and point out the characteristics and possible problems of different coupling methods.Finally,we discuss the major challenges and prospects of coupling physical signals and cell-free enzymatic catalytic systems in the field of CO_(2) fixation,suggesting possible strategies to improve the carbon sequestration capacity of such systems.展开更多
Accurate prediction of the frictional pressure drop is important for the design and operation of subsea oil and gas transporting system considering the length of the pipeline. The applicability of the correlations to ...Accurate prediction of the frictional pressure drop is important for the design and operation of subsea oil and gas transporting system considering the length of the pipeline. The applicability of the correlations to pipeline-riser flow needs evaluation since the flow condition in pipeline-riser is quite different from the original data where they were derived from. In the present study, a comprehensive evaluation of 24prevailing correlation in predicting frictional pressure drop is carried out based on experimentally measured data of air-water and air-oil two-phase flows in pipeline-riser. Experiments are performed in a system having different configuration of pipeline-riser with the inclination of the downcomer varied from-2°to-5°to investigated the effect of the elbow on the frictional pressure drop in the riser. The inlet gas velocity ranges from 0.03 to 6.2 m/s, and liquid velocity varies from 0.02 to 1.3 m/s. A total of885 experimental data points including 782 on air-water flows and 103 on air-oil flows are obtained and used to access the prediction ability of the correlations. Comparison of the predicted results with the measured data indicate that a majority of the investigated correlations under-predict the pressure drop on severe slugging. The result of this study highlights the requirement of new method considering the effect of pipe layout on the frictional pressure drop.展开更多
A new kind of non-Gaussian quantum catalyzed state is proposed via multiphoton measurements and two-mode squeezing as an input of thermal state.The characteristics of the generated multiphoton catalysis output state d...A new kind of non-Gaussian quantum catalyzed state is proposed via multiphoton measurements and two-mode squeezing as an input of thermal state.The characteristics of the generated multiphoton catalysis output state depends on the thermal parameter,catalyzed photon number and squeezing parameter.We then analyze the nonclassical properties by examining the photon number distribution,photocount distribution and partial negativity of the Wigner function.Our findings indicate that nonclassicality can be achieved through the implementation of multiphoton catalysis operations and modulated by the thermal parameter,catalyzed photon number and squeezing parameter.展开更多
Solid non-conjugated polymers have long been regarded as insulators due to deficiency of delocalizedπelectrons along the molecular chain framework.Up to date,origin of insulating polymer regulated charge transfer has...Solid non-conjugated polymers have long been regarded as insulators due to deficiency of delocalizedπelectrons along the molecular chain framework.Up to date,origin of insulating polymer regulated charge transfer has not yet been uncovered.In this work,we unleash the root origin of charge transport capability of insulating polymer in photocatalysis.We ascertain that insulating polymer plays crucial roles in fine tuning of electronic structure of transition metal chalcogenides(TMCs),which mainly include altering surface electron density of TMCs for accelerating charge transport kinetics,triggering the generation of defect over TMCs for prolonging carrier lifetime,and acting as hole-trapping mediator for retarding charge recombination.These synergistic roles contribute to the charge transfer of insulating polymer.Our work opens a new vista of utilizing solid insulating polymers for maneuvering charge transfer toward solar energy conversion.展开更多
Polymer flooding in fractured wells has been extensively applied in oilfields to enhance oil recovery.In contrast to water,polymer solution exhibits non-Newtonian and nonlinear behavior such as effects of shear thinni...Polymer flooding in fractured wells has been extensively applied in oilfields to enhance oil recovery.In contrast to water,polymer solution exhibits non-Newtonian and nonlinear behavior such as effects of shear thinning and shear thickening,polymer convection,diffusion,adsorption retention,inaccessible pore volume and reduced effective permeability.Meanwhile,the flux density and fracture conductivity along the hydraulic fracture are generally non-uniform due to the effects of pressure distribution,formation damage,and proppant breakage.In this paper,we present an oil-water two-phase flow model that captures these complex non-Newtonian and nonlinear behavior,and non-uniform fracture characteristics in fractured polymer flooding.The hydraulic fracture is firstly divided into two parts:high-conductivity fracture near the wellbore and low-conductivity fracture in the far-wellbore section.A hybrid grid system,including perpendicular bisection(PEBI)and Cartesian grid,is applied to discrete the partial differential flow equations,and the local grid refinement method is applied in the near-wellbore region to accurately calculate the pressure distribution and shear rate of polymer solution.The combination of polymer behavior characterizations and numerical flow simulations are applied,resulting in the calculation for the distribution of water saturation,polymer concentration and reservoir pressure.Compared with the polymer flooding well with uniform fracture conductivity,this non-uniform fracture conductivity model exhibits the larger pressure difference,and the shorter bilinear flow period due to the decrease of fracture flow ability in the far-wellbore section.The field case of the fall-off test demonstrates that the proposed method characterizes fracture characteristics more accurately,and yields fracture half-lengths that better match engineering reality,enabling a quantitative segmented characterization of the near-wellbore section with high fracture conductivity and the far-wellbore section with low fracture conductivity.The novelty of this paper is the analysis of pressure performances caused by the fracture dynamics and polymer rheology,as well as an analysis method that derives formation and fracture parameters based on the pressure and its derivative curves.展开更多
To meet the growing emission of water contaminants,the development of new materials that enhance the efficiency of the water treatment system is urgent.Ordered mesoporous materials provide opportunities in environment...To meet the growing emission of water contaminants,the development of new materials that enhance the efficiency of the water treatment system is urgent.Ordered mesoporous materials provide opportunities in environmental processing applications due to their exceptionally high surface areas,large pore sizes,and enough pore volumes.These properties might enhance the performance of materials concerning adsorption/catalysis capability,durability,and stability.In this review,we enumerate the ordered mesoporous materials as adsorbents/catalysts and their modifications in water pollution treatment from the past decade,including heavy metals(Hg^(2+),Pb^(2+),Cd^(2+),Cr^(6+),etc.),toxic anions(nitrate,phosphate,fluoride,etc.),and organic contaminants(organic dyes,antibiotics,etc.).These contributions demonstrate a deep understanding of the synergistic effect between the incorporated framework and homogeneous active centers.Besides,the challenges and perspectives of the future developments of ordered mesoporous materials in wastewater treatment are proposed.This work provides a theoretical basis and complete summary for the application of ordered mesoporous materials in the removal of contaminants from aqueous solutions.展开更多
Since the D-band center theory was proposed,it has been widely used in the fields of surface chemistry by almost all researchers,due to its easy understanding,convenient operation and relative accuracy.However,with th...Since the D-band center theory was proposed,it has been widely used in the fields of surface chemistry by almost all researchers,due to its easy understanding,convenient operation and relative accuracy.However,with the continuous development of material systems and modification strategies,researchers have gradually found that D-band center theory is usually effective for large metal particle systems,but for small metal particle systems or semiconductors,such as single atom systems,the opposite conclusion to the D-band center theory is often obtained.To solve the issue above,here we propose a bonding and anti-bonding orbitals stable electron intensity difference(BASED)theory for surface chemistry.The newly-proposed BASED theory can not only successfully explain the abnormal phenomena of D-band center theory,but also exhibits a higher accuracy for prediction of adsorption energy and bond length of intermediates on active sites.Importantly,a new phenomenon of the spin transition state in the adsorption process is observed based on the BASED theory,where the active center atom usually yields an unstable high spin transition state to enhance its adsorption capability in the adsorption process of intermediates when their distance is about 2.5Å.In short,the BASED theory can be considered as a general principle to understand catalytic mechanism of intermediates on surfaces.展开更多
Based on the displacement discontinuity method and the discrete fracture unified pipe network model,a sequential iterative numerical method was used to build a fracturing-production integrated numerical model of shale...Based on the displacement discontinuity method and the discrete fracture unified pipe network model,a sequential iterative numerical method was used to build a fracturing-production integrated numerical model of shale gas well considering the two-phase flow of gas and water.The model accounts for the influence of natural fractures and matrix properties on the fracturing process and directly applies post-fracturing formation pressure and water saturation distribution to subsequent well shut-in and production simulation,allowing for a more accurate fracturing-production integrated simulation.The results show that the reservoir physical properties have great impacts on fracture propagation,and the reasonable prediction of formation pressure and reservoir fluid distribution after the fracturing is critical to accurately predict the gas and fluid production of the shale gas wells.Compared with the conventional method,the proposed model can more accurately simulate the water and gas production by considering the impact of fracturing on both matrix pressure and water saturation.The established model is applied to the integrated fracturing-production simulation of practical horizontal shale gas wells.The simulation results are in good agreement with the practical production data,thus verifying the accuracy of the model.展开更多
The activity and selectivity of electrocatalytic CO_(2)reduction reaction(CO_(2)RR)to C_(2)products on metal catalysts can be regulated by molecular surfactants.However,the mechanism behind it remains elusive and deba...The activity and selectivity of electrocatalytic CO_(2)reduction reaction(CO_(2)RR)to C_(2)products on metal catalysts can be regulated by molecular surfactants.However,the mechanism behind it remains elusive and debatable.Herein,copper nanowires(Cu NWs)were fabricated and decorated with cobalt phthalocyanine(CoPc).The electronic interaction between the Cu NWs,CoPc,CO_(2) and CO_(2)RR intermediates were explored by density functional theory(DFT)calculations.It was found that the selectivity and activity of CO_(2)RR towards C_(2)products on Cu NWs were considerably enhanced from 35.2%to 69.9%by surface decoration of CoPc.DFT calculations revealed that CO_(2)RR can proceed in the interphase between Cu substrate and CoPc,and the CO_(2)RR intermediates could synergistically bond with both Cu and Co metal centre in CuNWs-CoPc,which favours the adsorption of CO_(2),CO and CO_(2)RR intermediates,thus reducing the free energy for CO-COcoupling towards C_(2)products.The synergistic interaction was further extended to phthalocyanine(Pc)and other metal phthalocyanine derivatives(MPc),where a relatively weaker synergistic interaction of COintermediates with MPc and Cu substrate and only a slight enhancement of CO_(2)RR towards C_(2) products were observed.This study demonstrates a synergistic catalysis pathway for CO_(2)RR,a novel perspective in interpreting the role of CoPc in enhancing the activity and selectivity of CO_(2)RR on Cu NWs,in contrast to the conventional tandem catalysis mechanism.展开更多
The gas-water two-phaseflow occurring as a result of fracturingfluidflowback phenomena is known to impact significantly the productivity of shale gas well.In this work,this two-phaseflow has been simulated in the framework...The gas-water two-phaseflow occurring as a result of fracturingfluidflowback phenomena is known to impact significantly the productivity of shale gas well.In this work,this two-phaseflow has been simulated in the framework of a hybrid approach partially relying on the embedded discrete fracture model(EDFM).This model assumes the region outside the stimulated reservoir volume(SRV)as a single-medium while the SRV region itself is described using a double-medium strategy which can account for thefluid exchange between the matrix and the micro-fractures.The shale gas adsorption,desorption,diffusion,gas slippage effect,fracture stress sensitivity,and capillary imbibition have been considered.The shale gas production,pore pressure distribution and water saturation distribution in the reservoir have been simulated.The influences of hydraulic fracture geometry and nonorthogonal hydraulic fractures on gas production have been determined and discussed accordingly.The simulation results show that the daily gas production has an upward and downward trend due to the presence of a large amount of fracturingfluid in the reservoir around the hydraulic fracture.The smaller the angle between the hydraulic fracture and the wellbore,the faster the daily production of shale gas wells decreases,and the lower the cumulative production.Nonplanar fractures can increase the control volume of hydraulic fractures and improve the production of shale gas wells.展开更多
Due to the coupling between the hydrodynamic equation and the phase-field equation in two-phase incompressible flows,it is desirable to develop efficient and high-order accurate numerical schemes that can decouple the...Due to the coupling between the hydrodynamic equation and the phase-field equation in two-phase incompressible flows,it is desirable to develop efficient and high-order accurate numerical schemes that can decouple these two equations.One popular and efficient strategy is to add an explicit stabilizing term to the convective velocity in the phase-field equation to decouple them.The resulting schemes are only first-order accurate in time,and it seems extremely difficult to generalize the idea of stabilization to the second-order or higher version.In this paper,we employ the spectral deferred correction method to improve the temporal accuracy,based on the first-order decoupled and energy-stable scheme constructed by the stabilization idea.The novelty lies in how the decoupling and linear implicit properties are maintained to improve the efficiency.Within the framework of the spatially discretized local discontinuous Galerkin method,the resulting numerical schemes are fully decoupled,efficient,and high-order accurate in both time and space.Numerical experiments are performed to validate the high-order accuracy and efficiency of the methods for solving phase-field models of two-phase incompressible flows.展开更多
In response to the complex characteristics of actual low-permeability tight reservoirs,this study develops a meshless-based numerical simulation method for oil-water two-phase flow in these reservoirs,considering comp...In response to the complex characteristics of actual low-permeability tight reservoirs,this study develops a meshless-based numerical simulation method for oil-water two-phase flow in these reservoirs,considering complex boundary shapes.Utilizing radial basis function point interpolation,the method approximates shape functions for unknown functions within the nodal influence domain.The shape functions constructed by the aforementioned meshless interpolation method haveδ-function properties,which facilitate the handling of essential aspects like the controlled bottom-hole flow pressure in horizontal wells.Moreover,the meshless method offers greater flexibility and freedom compared to grid cell discretization,making it simpler to discretize complex geometries.A variational principle for the flow control equation group is introduced using a weighted least squares meshless method,and the pressure distribution is solved implicitly.Example results demonstrate that the computational outcomes of the meshless point cloud model,which has a relatively small degree of freedom,are in close agreement with those of the Discrete Fracture Model(DFM)employing refined grid partitioning,with pressure calculation accuracy exceeding 98.2%.Compared to high-resolution grid-based computational methods,the meshless method can achieve a better balance between computational efficiency and accuracy.Additionally,the impact of fracture half-length on the productivity of horizontal wells is discussed.The results indicate that increasing the fracture half-length is an effective strategy for enhancing production from the perspective of cumulative oil production.展开更多
The main idea of this paper is what the resource of the serious error of the widely popular Chemical Reaction Mode catalysis Mechanism-CRMM is. The wrong definition of “catalysis, catalyst” by the catalytic academia...The main idea of this paper is what the resource of the serious error of the widely popular Chemical Reaction Mode catalysis Mechanism-CRMM is. The wrong definition of “catalysis, catalyst” by the catalytic academia boss leads to the wrong interpretation of “catalysis, catalyst” by linguists (Dictionary). The interpretation of “catalysis, catalyst” in a dictionary is misleading. The most fundamental reason for this error is that catalysis experts always believe that catalysts participate in chemical reactions. The result will appear as a series of impossible events. Such as catalysis cyclic reaction, opinions vary intermedium, catalysts repeated decomposition—formation, oxidation-reduction or life and death (enzyme), Sabatier’s principle and Boudart’s principle. The wrong theory leads the research and application of catalysts to the bottomless abyss, and industrial production suffers great losses. Electron Orbital Deformation-Recovere cyclic catalysis Mechanism-EODRM or Electron Cyclic Donate-Adopt catalysis Mechanism-ECDAM shows that the catalytic phenomenon is a physical phenomenon, not a chemical phenomenon, the catalyst does not participate in chemical reactions, only contact is the electron donate-adopt cycle, is the electron orbital deformation recovery cycle Chinese and foreign scholars should change the interpretation on the “catalysis, catalyst”, or add two new words: “contact and contactor”, it is to give up “catalysis, catalyst” altogether.展开更多
Energetic Semiconductor bridge(ESCB)based on reactive multilayered films(RMFs)has a promising application in the miniature and intelligence of initiator and pyrotechnics device.Understanding the ignition enhancement m...Energetic Semiconductor bridge(ESCB)based on reactive multilayered films(RMFs)has a promising application in the miniature and intelligence of initiator and pyrotechnics device.Understanding the ignition enhancement mechanism of RMFs on semiconductor bridge(SCB)during the ignition process is crucial for the engineering and practical application of advanced initiator and pyrotechnics devices.In this study,a one-dimensional(1D)gas-solid two-phase flow ignition model was established to study the ignition process of ESCB to charge particles based on the reactivity of Al/MoO_(3) RMFs.In order to fully consider the coupled exothermic between the RMFs and the SCB plasma during the ignition process,the heat release of chemical reaction in RMFs was used as an internal heat source in this model.It is found that the exothermal reaction in RMFs improved the ignition performance of SCB.In the process of plasma rapid condensation with heat release,the product of RMFs enhanced the heat transfer process between the gas phase and the solid charge particle,which accelerated the expansion of hot plasma,and heated the solid charge particle as well as gas phase region with low temperature.In addition,it made up for pressure loss in the gas phase.During the plasma dissipation process,the exothermal chemical reaction in RMFs acted as the main heating source to heat the charge particle,making the surface temperature of the charge particle,gas pressure,and gas temperature rise continuously.This result may yield significant advantages in providing a universal ignition model for miniaturized ignition devices.展开更多
The main purpose of this paper is to generalize the effect of two-phased demand and variable deterioration within the EOQ (Economic Order Quantity) framework. The rate of deterioration is a linear function of time. Th...The main purpose of this paper is to generalize the effect of two-phased demand and variable deterioration within the EOQ (Economic Order Quantity) framework. The rate of deterioration is a linear function of time. The two-phased demand function states the constant function for a certain period and the quadratic function of time for the rest part of the cycle time. No shortages as well as partial backlogging are allowed to occur. The mathematical expressions are derived for determining the optimal cycle time, order quantity and total cost function. An easy-to-use working procedure is provided to calculate the above quantities. A couple of numerical examples are cited to explain the theoretical results and sensitivity analysis of some selected examples is carried out.展开更多
Climate change is a reality. The burning of fossil fuels from oil, natural gas and coal is responsible for much of the pollution and the increase in the planet’s average temperature, which has raised discussions on t...Climate change is a reality. The burning of fossil fuels from oil, natural gas and coal is responsible for much of the pollution and the increase in the planet’s average temperature, which has raised discussions on the subject, given the emergencies related to climate. An energy transition to clean and renewable sources is necessary and urgent, but it will not be quick. In this sense, increasing the efficiency of oil extraction from existing sources is crucial, to avoid waste and the drilling of new wells. The purpose of this work was to add diffusive and dispersive terms to the Buckley-Leverett equation in order to incorporate extra phenomena in the temporal evolution between the water-oil and oil-water transitions in the pipeline. For this, the modified Buckley-Leverett equation was discretized via essentially weighted non-oscillatory schemes, coupled with a three-stage Runge-Kutta and a fourth-order centered finite difference methods. Then, computational simulations were performed and the results showed that new features emerge in the transitions, when compared to classical simulations. For instance, the dispersive term inhibits the diffusive term, adding oscillations, which indicates that the absorption of the fluid by the porous medium occurs in a non-homogeneous manner. Therefore, based on research such as this, decisions can be made regarding the replacement of the porous medium or the insertion of new components to delay the replacement.展开更多
Photothermal catalysis realizes the synergistic effect of solar energy and thermochemistry,which also has the potential to improve the reaction rate and optimize the selectivity.In this review,the research progress of...Photothermal catalysis realizes the synergistic effect of solar energy and thermochemistry,which also has the potential to improve the reaction rate and optimize the selectivity.In this review,the research progress of photothermal catalytic removal of volatile organic compounds(VOCs)by nano-catalysts in recent years is systematically reviewed.First,the fundamentals of photothermal catalysis and the fabrication of catalysts are described,and the design strategy of optimizing photothermal catalysis performance is proposed.Second,the performance for VOC degradation with photothermal catalysis is evaluated and compared for the batch and continuous systems.Particularly,the catalytic mechanism of VOC oxidation is systematically introduced based on experimental and theoretical study.Finally,the future limitations and challenges have been discussed,and potential research directions and priorities are highlighted.A broad view of recent photothermal catalyst fabrication,applications,challenges,and prospects can be systemically provided by this review.展开更多
Lithium–sulfur(Li-S)batteries have the advantages of high theoretical specific capacity(1675 mAh g^(−1)),rich sulfur resources,low production cost,and friendly environment,which makes it one of the most promising nex...Lithium–sulfur(Li-S)batteries have the advantages of high theoretical specific capacity(1675 mAh g^(−1)),rich sulfur resources,low production cost,and friendly environment,which makes it one of the most promising next-generation rechargeable energy storage devices.However,the“shuttle effect”of polysulfide results in the passivation of metal lithium anode,the decrease of battery capacity and coulombic efficiency,and the deterioration of cycle stability.To realize the commercialization of Li-S batteries,its serious“shuttle effect”needs to be suppress.The commercial separators are ineffective to suppress this effect because of its large pore size.Therefore,it is an effective strategy to modify the separator surface and introduce functional modified layer.In addition to the blocking strategy,the catalysis of polysulfide conversion reaction is also an important factor hindering the migration of polysulfides.In this review,the principles of separator modification,functionalization,and catalysis in Li-S batteries are reviewed.Furthermore,the research trend of separator functionalization and polysulfide catalysis in the future is prospected.展开更多
Sustainable ammonia synthesis at ambient conditions that relies on renewable sources of energy and feedstocks is globally sought to replace the Haber-Bosch process.Here,using nitrogen and water as raw materials,a nont...Sustainable ammonia synthesis at ambient conditions that relies on renewable sources of energy and feedstocks is globally sought to replace the Haber-Bosch process.Here,using nitrogen and water as raw materials,a nonthermal plasma catalysis approach is demonstrated as an effective powerto-chemicals conversion strategy for ammonia production.By sustaining a highly reactive environment,successful plasma-catalytic production of NH_(3) was achieved from the dissociation of N_(2) and H_(2)O under mild conditions.Plasma-induced vibrational excitation is found to decrease the N_(2) and H_(2)O dissociation barriers,with the presence of matched catalysts in the nonthermal plasma discharge reactor contributing significantly to molecular dissociation on the catalyst surface.Density functional theory calculations for the activation energy barrier for the dissociation suggest that ruthenium catalysts supported on magnesium oxide exhibit superior performance over other catalysts in NH_(3) production by lowering the activation energy for the dissociative adsorption of N_(2) down to 1.07 eV.The highest production rate,2.67 mmol gcat.^(-1) h^(-1),was obtained using ruthenium catalyst supported on magnesium oxide.This work highlights the potential of nonthermal plasma catalysis for the activation of renewable sources to serve as a new platform for sustainable ammonia production.展开更多
Although lithium-sulfur batteries(Li SBs)are regarded as one of the most promising candidates for the next-generation energy storage system,the actual industrial application is hindered by the sluggish solid–liquid p...Although lithium-sulfur batteries(Li SBs)are regarded as one of the most promising candidates for the next-generation energy storage system,the actual industrial application is hindered by the sluggish solid–liquid phase conversion kinetics,severe shuttle effect,and low sulfur loadings.Herein,a zeolitic imidazolate framework(ZIF)derived heterogeneous ZnSe-CoSe nanoparticles encapsulated in hollow N-doped carbon nanocage(ZnSe-CoSe-HNC)was designed by etching with tannic acid as a multifunctional electrocatalyst to boost the polysulfide conversion kinetics in LiSBs.The hollow structure in ZIF ensures large inner voids for sulfur and buffering volume expansions.Abundant exposed ZnSe-CoSe heterogeneous interfaces serve as bifunctional adsorption-catalytic centers to accelerate the conversion kinetics and alleviate the shuttle effect.Together with the highly conductive framework,the ZnSe-CoSeHNC/S cathode exhibits a high initial reversible capacity of 1305.3 m A h g-1at 0.2 C,high-rate capability,and reliable cycling stability under high sulfur loading and lean electrolyte(maintaining at 745 m A h g-1after 200 cycles with a high sulfur loading of 6.4 mg cm-2and a low electrolyte/sulfur ratio of 6μL mg^(-1)).Theoretical calculations have demonstrated the heterostructures of ZnSe-CoSe offer higher binding energy to lithium polysulfides than that of ZnSe or CoSe,facilitating the electron transfer to lithium polysulfides.This work provides a novel heterostructure with superior catalytic ability and hollow conductive architecture,paving the way for the practical application of functional sulfur electrodes.展开更多
基金supported by the National Key R&D Program of China (2018YFA0901700)National Natural Science Foundation of China (22278241)+1 种基金a grant from the Institute Guo Qiang, Tsinghua University (2021GQG1016)Department of Chemical Engineering-iBHE Joint Cooperation Fund。
文摘The increasing atmospheric carbon dioxide (CO_(2)) concentration has exposed a series of crises in the earth's ecological environment.How to effectively fix and convert carbon dioxide into products with added value has attracted the attention of many researchers.Cell-free enzyme catalytic system coupled with electrical and light have been a promising attempt in the field of biological carbon fixation in recent years.In this review,the research progresses of photoenzyme catalysis,electroenzyme catalysis and photo-electroenzyme catalysis for converting carbon dioxide into chemical products in cell-free systems are systematically summarized.We focus on reviewing and comparing various coupling methods and principles of photoenzyme catalysis and electroenzyme catalysis in cell-free systems,especially the materials used in the construction of the coupling system,and analyze and point out the characteristics and possible problems of different coupling methods.Finally,we discuss the major challenges and prospects of coupling physical signals and cell-free enzymatic catalytic systems in the field of CO_(2) fixation,suggesting possible strategies to improve the carbon sequestration capacity of such systems.
基金the support of the Opening Fund of State Key Laboratory of Multiphase Flow in Power Engineering(SKLMF-KF-2102)。
文摘Accurate prediction of the frictional pressure drop is important for the design and operation of subsea oil and gas transporting system considering the length of the pipeline. The applicability of the correlations to pipeline-riser flow needs evaluation since the flow condition in pipeline-riser is quite different from the original data where they were derived from. In the present study, a comprehensive evaluation of 24prevailing correlation in predicting frictional pressure drop is carried out based on experimentally measured data of air-water and air-oil two-phase flows in pipeline-riser. Experiments are performed in a system having different configuration of pipeline-riser with the inclination of the downcomer varied from-2°to-5°to investigated the effect of the elbow on the frictional pressure drop in the riser. The inlet gas velocity ranges from 0.03 to 6.2 m/s, and liquid velocity varies from 0.02 to 1.3 m/s. A total of885 experimental data points including 782 on air-water flows and 103 on air-oil flows are obtained and used to access the prediction ability of the correlations. Comparison of the predicted results with the measured data indicate that a majority of the investigated correlations under-predict the pressure drop on severe slugging. The result of this study highlights the requirement of new method considering the effect of pipe layout on the frictional pressure drop.
基金supported by the National Natural Science Foundation of China (Grant No.11347026)the Natural Science Foundation of Shandong Province,China (Grant Nos.ZR2020MA085 and ZR2020MF113)。
文摘A new kind of non-Gaussian quantum catalyzed state is proposed via multiphoton measurements and two-mode squeezing as an input of thermal state.The characteristics of the generated multiphoton catalysis output state depends on the thermal parameter,catalyzed photon number and squeezing parameter.We then analyze the nonclassical properties by examining the photon number distribution,photocount distribution and partial negativity of the Wigner function.Our findings indicate that nonclassicality can be achieved through the implementation of multiphoton catalysis operations and modulated by the thermal parameter,catalyzed photon number and squeezing parameter.
文摘Solid non-conjugated polymers have long been regarded as insulators due to deficiency of delocalizedπelectrons along the molecular chain framework.Up to date,origin of insulating polymer regulated charge transfer has not yet been uncovered.In this work,we unleash the root origin of charge transport capability of insulating polymer in photocatalysis.We ascertain that insulating polymer plays crucial roles in fine tuning of electronic structure of transition metal chalcogenides(TMCs),which mainly include altering surface electron density of TMCs for accelerating charge transport kinetics,triggering the generation of defect over TMCs for prolonging carrier lifetime,and acting as hole-trapping mediator for retarding charge recombination.These synergistic roles contribute to the charge transfer of insulating polymer.Our work opens a new vista of utilizing solid insulating polymers for maneuvering charge transfer toward solar energy conversion.
基金This work is supported by the National Natural Science Foundation of China(No.52104049)the Young Elite Scientist Sponsorship Program by Beijing Association for Science and Technology(No.BYESS2023262)Science Foundation of China University of Petroleum,Beijing(No.2462022BJRC004).
文摘Polymer flooding in fractured wells has been extensively applied in oilfields to enhance oil recovery.In contrast to water,polymer solution exhibits non-Newtonian and nonlinear behavior such as effects of shear thinning and shear thickening,polymer convection,diffusion,adsorption retention,inaccessible pore volume and reduced effective permeability.Meanwhile,the flux density and fracture conductivity along the hydraulic fracture are generally non-uniform due to the effects of pressure distribution,formation damage,and proppant breakage.In this paper,we present an oil-water two-phase flow model that captures these complex non-Newtonian and nonlinear behavior,and non-uniform fracture characteristics in fractured polymer flooding.The hydraulic fracture is firstly divided into two parts:high-conductivity fracture near the wellbore and low-conductivity fracture in the far-wellbore section.A hybrid grid system,including perpendicular bisection(PEBI)and Cartesian grid,is applied to discrete the partial differential flow equations,and the local grid refinement method is applied in the near-wellbore region to accurately calculate the pressure distribution and shear rate of polymer solution.The combination of polymer behavior characterizations and numerical flow simulations are applied,resulting in the calculation for the distribution of water saturation,polymer concentration and reservoir pressure.Compared with the polymer flooding well with uniform fracture conductivity,this non-uniform fracture conductivity model exhibits the larger pressure difference,and the shorter bilinear flow period due to the decrease of fracture flow ability in the far-wellbore section.The field case of the fall-off test demonstrates that the proposed method characterizes fracture characteristics more accurately,and yields fracture half-lengths that better match engineering reality,enabling a quantitative segmented characterization of the near-wellbore section with high fracture conductivity and the far-wellbore section with low fracture conductivity.The novelty of this paper is the analysis of pressure performances caused by the fracture dynamics and polymer rheology,as well as an analysis method that derives formation and fracture parameters based on the pressure and its derivative curves.
基金supported by the National Natural Science Foundation of China(52370041)National Natural Science Foundation of China(21976134 and 21707104)State Key Laboratory of Pollution treatment and Resource Reuse Foundation(NO.PCRRK21001).
文摘To meet the growing emission of water contaminants,the development of new materials that enhance the efficiency of the water treatment system is urgent.Ordered mesoporous materials provide opportunities in environmental processing applications due to their exceptionally high surface areas,large pore sizes,and enough pore volumes.These properties might enhance the performance of materials concerning adsorption/catalysis capability,durability,and stability.In this review,we enumerate the ordered mesoporous materials as adsorbents/catalysts and their modifications in water pollution treatment from the past decade,including heavy metals(Hg^(2+),Pb^(2+),Cd^(2+),Cr^(6+),etc.),toxic anions(nitrate,phosphate,fluoride,etc.),and organic contaminants(organic dyes,antibiotics,etc.).These contributions demonstrate a deep understanding of the synergistic effect between the incorporated framework and homogeneous active centers.Besides,the challenges and perspectives of the future developments of ordered mesoporous materials in wastewater treatment are proposed.This work provides a theoretical basis and complete summary for the application of ordered mesoporous materials in the removal of contaminants from aqueous solutions.
文摘Since the D-band center theory was proposed,it has been widely used in the fields of surface chemistry by almost all researchers,due to its easy understanding,convenient operation and relative accuracy.However,with the continuous development of material systems and modification strategies,researchers have gradually found that D-band center theory is usually effective for large metal particle systems,but for small metal particle systems or semiconductors,such as single atom systems,the opposite conclusion to the D-band center theory is often obtained.To solve the issue above,here we propose a bonding and anti-bonding orbitals stable electron intensity difference(BASED)theory for surface chemistry.The newly-proposed BASED theory can not only successfully explain the abnormal phenomena of D-band center theory,but also exhibits a higher accuracy for prediction of adsorption energy and bond length of intermediates on active sites.Importantly,a new phenomenon of the spin transition state in the adsorption process is observed based on the BASED theory,where the active center atom usually yields an unstable high spin transition state to enhance its adsorption capability in the adsorption process of intermediates when their distance is about 2.5Å.In short,the BASED theory can be considered as a general principle to understand catalytic mechanism of intermediates on surfaces.
基金Supported by the National Natural Science Foundation of China(52374043)Key Program of the National Natural Science Foundation of China(52234003).
文摘Based on the displacement discontinuity method and the discrete fracture unified pipe network model,a sequential iterative numerical method was used to build a fracturing-production integrated numerical model of shale gas well considering the two-phase flow of gas and water.The model accounts for the influence of natural fractures and matrix properties on the fracturing process and directly applies post-fracturing formation pressure and water saturation distribution to subsequent well shut-in and production simulation,allowing for a more accurate fracturing-production integrated simulation.The results show that the reservoir physical properties have great impacts on fracture propagation,and the reasonable prediction of formation pressure and reservoir fluid distribution after the fracturing is critical to accurately predict the gas and fluid production of the shale gas wells.Compared with the conventional method,the proposed model can more accurately simulate the water and gas production by considering the impact of fracturing on both matrix pressure and water saturation.The established model is applied to the integrated fracturing-production simulation of practical horizontal shale gas wells.The simulation results are in good agreement with the practical production data,thus verifying the accuracy of the model.
基金supported by the National Natural Science Foundation of China(U2032151,22272059)。
文摘The activity and selectivity of electrocatalytic CO_(2)reduction reaction(CO_(2)RR)to C_(2)products on metal catalysts can be regulated by molecular surfactants.However,the mechanism behind it remains elusive and debatable.Herein,copper nanowires(Cu NWs)were fabricated and decorated with cobalt phthalocyanine(CoPc).The electronic interaction between the Cu NWs,CoPc,CO_(2) and CO_(2)RR intermediates were explored by density functional theory(DFT)calculations.It was found that the selectivity and activity of CO_(2)RR towards C_(2)products on Cu NWs were considerably enhanced from 35.2%to 69.9%by surface decoration of CoPc.DFT calculations revealed that CO_(2)RR can proceed in the interphase between Cu substrate and CoPc,and the CO_(2)RR intermediates could synergistically bond with both Cu and Co metal centre in CuNWs-CoPc,which favours the adsorption of CO_(2),CO and CO_(2)RR intermediates,thus reducing the free energy for CO-COcoupling towards C_(2)products.The synergistic interaction was further extended to phthalocyanine(Pc)and other metal phthalocyanine derivatives(MPc),where a relatively weaker synergistic interaction of COintermediates with MPc and Cu substrate and only a slight enhancement of CO_(2)RR towards C_(2) products were observed.This study demonstrates a synergistic catalysis pathway for CO_(2)RR,a novel perspective in interpreting the role of CoPc in enhancing the activity and selectivity of CO_(2)RR on Cu NWs,in contrast to the conventional tandem catalysis mechanism.
基金supported by the National Natural Science Foundation of China(Grant Nos.U19A2043 and 52174033)Natural Science Foundation of Sichuan Province(NSFSC)(No.2022NSFSC0971)the Science and Technology Cooperation Project of the CNPC-SWPU Innovation Alliance.
文摘The gas-water two-phaseflow occurring as a result of fracturingfluidflowback phenomena is known to impact significantly the productivity of shale gas well.In this work,this two-phaseflow has been simulated in the framework of a hybrid approach partially relying on the embedded discrete fracture model(EDFM).This model assumes the region outside the stimulated reservoir volume(SRV)as a single-medium while the SRV region itself is described using a double-medium strategy which can account for thefluid exchange between the matrix and the micro-fractures.The shale gas adsorption,desorption,diffusion,gas slippage effect,fracture stress sensitivity,and capillary imbibition have been considered.The shale gas production,pore pressure distribution and water saturation distribution in the reservoir have been simulated.The influences of hydraulic fracture geometry and nonorthogonal hydraulic fractures on gas production have been determined and discussed accordingly.The simulation results show that the daily gas production has an upward and downward trend due to the presence of a large amount of fracturingfluid in the reservoir around the hydraulic fracture.The smaller the angle between the hydraulic fracture and the wellbore,the faster the daily production of shale gas wells decreases,and the lower the cumulative production.Nonplanar fractures can increase the control volume of hydraulic fractures and improve the production of shale gas wells.
基金supported by the NSFC Grant no.12271492the Natural Science Foundation of Henan Province of China Grant no.222300420550+1 种基金supported by the NSFC Grant no.12271498the National Key R&D Program of China Grant no.2022YFA1005202/2022YFA1005200.
文摘Due to the coupling between the hydrodynamic equation and the phase-field equation in two-phase incompressible flows,it is desirable to develop efficient and high-order accurate numerical schemes that can decouple these two equations.One popular and efficient strategy is to add an explicit stabilizing term to the convective velocity in the phase-field equation to decouple them.The resulting schemes are only first-order accurate in time,and it seems extremely difficult to generalize the idea of stabilization to the second-order or higher version.In this paper,we employ the spectral deferred correction method to improve the temporal accuracy,based on the first-order decoupled and energy-stable scheme constructed by the stabilization idea.The novelty lies in how the decoupling and linear implicit properties are maintained to improve the efficiency.Within the framework of the spatially discretized local discontinuous Galerkin method,the resulting numerical schemes are fully decoupled,efficient,and high-order accurate in both time and space.Numerical experiments are performed to validate the high-order accuracy and efficiency of the methods for solving phase-field models of two-phase incompressible flows.
文摘In response to the complex characteristics of actual low-permeability tight reservoirs,this study develops a meshless-based numerical simulation method for oil-water two-phase flow in these reservoirs,considering complex boundary shapes.Utilizing radial basis function point interpolation,the method approximates shape functions for unknown functions within the nodal influence domain.The shape functions constructed by the aforementioned meshless interpolation method haveδ-function properties,which facilitate the handling of essential aspects like the controlled bottom-hole flow pressure in horizontal wells.Moreover,the meshless method offers greater flexibility and freedom compared to grid cell discretization,making it simpler to discretize complex geometries.A variational principle for the flow control equation group is introduced using a weighted least squares meshless method,and the pressure distribution is solved implicitly.Example results demonstrate that the computational outcomes of the meshless point cloud model,which has a relatively small degree of freedom,are in close agreement with those of the Discrete Fracture Model(DFM)employing refined grid partitioning,with pressure calculation accuracy exceeding 98.2%.Compared to high-resolution grid-based computational methods,the meshless method can achieve a better balance between computational efficiency and accuracy.Additionally,the impact of fracture half-length on the productivity of horizontal wells is discussed.The results indicate that increasing the fracture half-length is an effective strategy for enhancing production from the perspective of cumulative oil production.
文摘The main idea of this paper is what the resource of the serious error of the widely popular Chemical Reaction Mode catalysis Mechanism-CRMM is. The wrong definition of “catalysis, catalyst” by the catalytic academia boss leads to the wrong interpretation of “catalysis, catalyst” by linguists (Dictionary). The interpretation of “catalysis, catalyst” in a dictionary is misleading. The most fundamental reason for this error is that catalysis experts always believe that catalysts participate in chemical reactions. The result will appear as a series of impossible events. Such as catalysis cyclic reaction, opinions vary intermedium, catalysts repeated decomposition—formation, oxidation-reduction or life and death (enzyme), Sabatier’s principle and Boudart’s principle. The wrong theory leads the research and application of catalysts to the bottomless abyss, and industrial production suffers great losses. Electron Orbital Deformation-Recovere cyclic catalysis Mechanism-EODRM or Electron Cyclic Donate-Adopt catalysis Mechanism-ECDAM shows that the catalytic phenomenon is a physical phenomenon, not a chemical phenomenon, the catalyst does not participate in chemical reactions, only contact is the electron donate-adopt cycle, is the electron orbital deformation recovery cycle Chinese and foreign scholars should change the interpretation on the “catalysis, catalyst”, or add two new words: “contact and contactor”, it is to give up “catalysis, catalyst” altogether.
基金supported by the National Natural Science Foundation of China(Grant Nos.22275092,52102107 and 52372084)the Fundamental Research Funds for the Central Universities(Grant No.30923010920)。
文摘Energetic Semiconductor bridge(ESCB)based on reactive multilayered films(RMFs)has a promising application in the miniature and intelligence of initiator and pyrotechnics device.Understanding the ignition enhancement mechanism of RMFs on semiconductor bridge(SCB)during the ignition process is crucial for the engineering and practical application of advanced initiator and pyrotechnics devices.In this study,a one-dimensional(1D)gas-solid two-phase flow ignition model was established to study the ignition process of ESCB to charge particles based on the reactivity of Al/MoO_(3) RMFs.In order to fully consider the coupled exothermic between the RMFs and the SCB plasma during the ignition process,the heat release of chemical reaction in RMFs was used as an internal heat source in this model.It is found that the exothermal reaction in RMFs improved the ignition performance of SCB.In the process of plasma rapid condensation with heat release,the product of RMFs enhanced the heat transfer process between the gas phase and the solid charge particle,which accelerated the expansion of hot plasma,and heated the solid charge particle as well as gas phase region with low temperature.In addition,it made up for pressure loss in the gas phase.During the plasma dissipation process,the exothermal chemical reaction in RMFs acted as the main heating source to heat the charge particle,making the surface temperature of the charge particle,gas pressure,and gas temperature rise continuously.This result may yield significant advantages in providing a universal ignition model for miniaturized ignition devices.
文摘The main purpose of this paper is to generalize the effect of two-phased demand and variable deterioration within the EOQ (Economic Order Quantity) framework. The rate of deterioration is a linear function of time. The two-phased demand function states the constant function for a certain period and the quadratic function of time for the rest part of the cycle time. No shortages as well as partial backlogging are allowed to occur. The mathematical expressions are derived for determining the optimal cycle time, order quantity and total cost function. An easy-to-use working procedure is provided to calculate the above quantities. A couple of numerical examples are cited to explain the theoretical results and sensitivity analysis of some selected examples is carried out.
文摘Climate change is a reality. The burning of fossil fuels from oil, natural gas and coal is responsible for much of the pollution and the increase in the planet’s average temperature, which has raised discussions on the subject, given the emergencies related to climate. An energy transition to clean and renewable sources is necessary and urgent, but it will not be quick. In this sense, increasing the efficiency of oil extraction from existing sources is crucial, to avoid waste and the drilling of new wells. The purpose of this work was to add diffusive and dispersive terms to the Buckley-Leverett equation in order to incorporate extra phenomena in the temporal evolution between the water-oil and oil-water transitions in the pipeline. For this, the modified Buckley-Leverett equation was discretized via essentially weighted non-oscillatory schemes, coupled with a three-stage Runge-Kutta and a fourth-order centered finite difference methods. Then, computational simulations were performed and the results showed that new features emerge in the transitions, when compared to classical simulations. For instance, the dispersive term inhibits the diffusive term, adding oscillations, which indicates that the absorption of the fluid by the porous medium occurs in a non-homogeneous manner. Therefore, based on research such as this, decisions can be made regarding the replacement of the porous medium or the insertion of new components to delay the replacement.
基金sponsored financially by the National Natural Science Foundation of China (No.21906104 and No.12175145)the Shanghai Rising-Star Program (21QA1406600).
文摘Photothermal catalysis realizes the synergistic effect of solar energy and thermochemistry,which also has the potential to improve the reaction rate and optimize the selectivity.In this review,the research progress of photothermal catalytic removal of volatile organic compounds(VOCs)by nano-catalysts in recent years is systematically reviewed.First,the fundamentals of photothermal catalysis and the fabrication of catalysts are described,and the design strategy of optimizing photothermal catalysis performance is proposed.Second,the performance for VOC degradation with photothermal catalysis is evaluated and compared for the batch and continuous systems.Particularly,the catalytic mechanism of VOC oxidation is systematically introduced based on experimental and theoretical study.Finally,the future limitations and challenges have been discussed,and potential research directions and priorities are highlighted.A broad view of recent photothermal catalyst fabrication,applications,challenges,and prospects can be systemically provided by this review.
基金support of the National Natural Science Foundation of China(No.21773188,No.22179109)central universities fundamental research fund(XDJK2019AA002)Chongqing Natural Science fund(cstc2020jcyj-bshx0047,cstc2021jcyj-bsh0173).
文摘Lithium–sulfur(Li-S)batteries have the advantages of high theoretical specific capacity(1675 mAh g^(−1)),rich sulfur resources,low production cost,and friendly environment,which makes it one of the most promising next-generation rechargeable energy storage devices.However,the“shuttle effect”of polysulfide results in the passivation of metal lithium anode,the decrease of battery capacity and coulombic efficiency,and the deterioration of cycle stability.To realize the commercialization of Li-S batteries,its serious“shuttle effect”needs to be suppress.The commercial separators are ineffective to suppress this effect because of its large pore size.Therefore,it is an effective strategy to modify the separator surface and introduce functional modified layer.In addition to the blocking strategy,the catalysis of polysulfide conversion reaction is also an important factor hindering the migration of polysulfides.In this review,the principles of separator modification,functionalization,and catalysis in Li-S batteries are reviewed.Furthermore,the research trend of separator functionalization and polysulfide catalysis in the future is prospected.
基金partially supported by the Australian Research Council(ARC)the National Science Fund for Distinguished Young Scholars(grant number 51925703)。
文摘Sustainable ammonia synthesis at ambient conditions that relies on renewable sources of energy and feedstocks is globally sought to replace the Haber-Bosch process.Here,using nitrogen and water as raw materials,a nonthermal plasma catalysis approach is demonstrated as an effective powerto-chemicals conversion strategy for ammonia production.By sustaining a highly reactive environment,successful plasma-catalytic production of NH_(3) was achieved from the dissociation of N_(2) and H_(2)O under mild conditions.Plasma-induced vibrational excitation is found to decrease the N_(2) and H_(2)O dissociation barriers,with the presence of matched catalysts in the nonthermal plasma discharge reactor contributing significantly to molecular dissociation on the catalyst surface.Density functional theory calculations for the activation energy barrier for the dissociation suggest that ruthenium catalysts supported on magnesium oxide exhibit superior performance over other catalysts in NH_(3) production by lowering the activation energy for the dissociative adsorption of N_(2) down to 1.07 eV.The highest production rate,2.67 mmol gcat.^(-1) h^(-1),was obtained using ruthenium catalyst supported on magnesium oxide.This work highlights the potential of nonthermal plasma catalysis for the activation of renewable sources to serve as a new platform for sustainable ammonia production.
基金financially supported by the Natural Science Foundation of Shandong Province,China(ZR2021QE192)the National Natural Science Foundation of China(21975154,22179078)+1 种基金the Postdoctoral Science Foundation of China(2018M63074)Qingdao Post-doctoral Applied Research Project(QDBSH20220202040)。
文摘Although lithium-sulfur batteries(Li SBs)are regarded as one of the most promising candidates for the next-generation energy storage system,the actual industrial application is hindered by the sluggish solid–liquid phase conversion kinetics,severe shuttle effect,and low sulfur loadings.Herein,a zeolitic imidazolate framework(ZIF)derived heterogeneous ZnSe-CoSe nanoparticles encapsulated in hollow N-doped carbon nanocage(ZnSe-CoSe-HNC)was designed by etching with tannic acid as a multifunctional electrocatalyst to boost the polysulfide conversion kinetics in LiSBs.The hollow structure in ZIF ensures large inner voids for sulfur and buffering volume expansions.Abundant exposed ZnSe-CoSe heterogeneous interfaces serve as bifunctional adsorption-catalytic centers to accelerate the conversion kinetics and alleviate the shuttle effect.Together with the highly conductive framework,the ZnSe-CoSeHNC/S cathode exhibits a high initial reversible capacity of 1305.3 m A h g-1at 0.2 C,high-rate capability,and reliable cycling stability under high sulfur loading and lean electrolyte(maintaining at 745 m A h g-1after 200 cycles with a high sulfur loading of 6.4 mg cm-2and a low electrolyte/sulfur ratio of 6μL mg^(-1)).Theoretical calculations have demonstrated the heterostructures of ZnSe-CoSe offer higher binding energy to lithium polysulfides than that of ZnSe or CoSe,facilitating the electron transfer to lithium polysulfides.This work provides a novel heterostructure with superior catalytic ability and hollow conductive architecture,paving the way for the practical application of functional sulfur electrodes.