Penthorum chinense Pursh is rich in gallic acid, which has antioxidant, anti-inflammatory, anti-fungal and antitumor activities. In order to optimize their extraction conditions, various extraction parameters were cho...Penthorum chinense Pursh is rich in gallic acid, which has antioxidant, anti-inflammatory, anti-fungal and antitumor activities. In order to optimize their extraction conditions, various extraction parameters were chosen to identify their effects on gallic acid extraction. With extraction amount of gallic acid as index, based on single factor analysis, influence of solid/liquid ratio, ethanol concentration, fetch time and extraction temperature on extraction technology were investigated by orthogonal test. The optimization conditions for gallic acid extraction were determined as follows: ethanol concentration 60%, extraction time 2.5 h, temperature 90°C and solid/liquid ratio 1:30. The corresponding gallic acid content was 4.85%. This optimized extraction process was stable and feasible.展开更多
In this work, a green and effective corrosion inhibitor of functionalized carbon dots(FCDs) was synthesized by the conjugation of imidazole and citric acid carbon dots(CA-CDs). The corrosion inhibition behavior of FCD...In this work, a green and effective corrosion inhibitor of functionalized carbon dots(FCDs) was synthesized by the conjugation of imidazole and citric acid carbon dots(CA-CDs). The corrosion inhibition behavior of FCDs for Q235 steel in 1 M HCl solution was systematically investigated by electrochemical analysis, corrosion morphology and adsorption isotherm. The electrochemical results implied that the as-prepared FCDs inhibitor could effectively suppress the corrosion of Q235 steel in 1 M HCl solution. At the same time, the inhibition efficiency of steel in 1 M HCl solution was more than 90% when the inhibitor concentration exceeded 100 mg/L. This excellent property was attributed to the coverage of adsorption film on the steel surface, which conformed to the Langmuir adsorption model. In addition, the analysis of adsorption isotherm displayed that the adsorption mechanism was the physicochemical interaction at the steel/solution interface.展开更多
The magnesium sulfate leaching technology for the ion-absorbed rare earths ore can solve the ammonia pollution problem existing in ammonium sulfate leaching process. However, the leaching capacity of magnesium sulfate...The magnesium sulfate leaching technology for the ion-absorbed rare earths ore can solve the ammonia pollution problem existing in ammonium sulfate leaching process. However, the leaching capacity of magnesium sulfate is slightly weaker than that of ammonium sulfate, resulting in a bigger consumption of magnesium sulfate. In this paper, the MgSO4-ascorbic acid compound leaching agent had been demonstrated to deal with the ion-absorbed rare earths ore. The ascorbic acid could form a stable coordination with rare earth ions, so that it can strengthen the leaching of ion-exchangeable phase.Moreover, ascorbic acid has a strong reductive property, it can leach the colloidal sediment phase rare earth as well. The present study investigates the effect of the initial pH and the composition of leaching agent on the rare earth leaching. It is determined that the rare earth leaching efficiency is 107.5% under the condition of pH 2.00,0.15 mol/L magnesium sulfate and 1.0 g/L ascorbic acid in leaching agent. In this case, the content of the ion-exchangeable phase and colloidal sediment phase rare earth in the leaching residues are both only 0.02‰. The leaching efficiency of colloid sediment phase rare earth can be 85.7%,so that the Ce partition in the leaching liquor increases to be 5.77%. The magnesium-ascorbic acid compound leaching agent is proposed to be a promising choice to deal with the ion-absorbed rare earths ore, which can realize the efficient leaching, low consumption of MgSO4 and environmentally friendly leaching.展开更多
The coarsening behavior of(Ni,Co)2Si particles in Cu-Ni-Co-Si alloy was investigated by experimental observations and coarsening kinetics calculations when aged at 450,500,550 and 600℃ for different durations.The res...The coarsening behavior of(Ni,Co)2Si particles in Cu-Ni-Co-Si alloy was investigated by experimental observations and coarsening kinetics calculations when aged at 450,500,550 and 600℃ for different durations.The results show that the critical particle radius for coherence mismatch is found to be 10.3 nm,and particles larger than 25 nm are generally semi-coherent.The relationship of(Ni,Co)2Si particles size and aging time follows Lifshitz,Slyosov and Wagner(LSW) theory.The particle size distributions fit well to the LSW theoretical distribution.The activation energy for(Ni,Co)2Si coarsening is accurately determined to be(216.21 ± 5.18)kJ mol-1 when considering the effect of temperature on the solution concentrations in matrix.The coarsening of(Ni,Co)2Si particles in Cu-Ni-Co-Si alloy is controlled by diffusion of Ni,Co and Si in Cu matrix.The growth of particles for long durations suggests that vacancies can be trapped within the structure for long time despite their mobility.展开更多
The effects of Mn and Cr contents on bainitic transformation kinetics,microstructures and mechanical properties of high-carbon low alloy steels after austempered at 230,300 and 350 ℃ were determined by dilatometry,op...The effects of Mn and Cr contents on bainitic transformation kinetics,microstructures and mechanical properties of high-carbon low alloy steels after austempered at 230,300 and 350 ℃ were determined by dilatometry,optical microscopy,scanning electron microscopy,X-ray diffraction and tensile tests. The results showed that Mn and Cr can extend bainitic incubation period and completion time,and with the increase of Mn and Cr content,the bainitic ferrite plate thickness decreased and the volume fraction of retained austenite increased. TRIP（ transformation induced plasticity） effect was observed during tensile testing which improved the overall mechanical property. The increase of Mn concentration can improve the strength to a certain extent,but reduce the ductility. The increase of Cr concentration can improve the ductility of bainitic steels which transformed at a low temperature. The low temperature bainitic steel austempered at 230 ℃ exhibited excellent mechanical properties with ultimate tensile strength of（ 2146 ± 11） MPa and total elongation of（ 12. 95 ± 0. 15） %.展开更多
Relationship between atomic local structures and Curie temperature of NdFeB permanent magnets was investigated semi-quantitatively using synchrotron radiation technique. Fe K-edge X-ray absorption spectroscopy(XAS) wa...Relationship between atomic local structures and Curie temperature of NdFeB permanent magnets was investigated semi-quantitatively using synchrotron radiation technique. Fe K-edge X-ray absorption spectroscopy(XAS) was employed to study the local structure of Fe atoms for samples before and after doping Dy, Tb or Gd. It is found that the bond lengths and coordination numbers are changed. Thus, the exchange interaction between Fe atoms increases with Dy, Tb or Gd doping, resulting in the improvement of Curie temperature of NdFeB permanent magnets. The doping effect is proven by experimental measurement of the magnetic properties. Microstructural characterization using scanning electron microscopy(SEM) was also used to further analyze the effect of different rare earth elements doping on Curie temperature of NdFeB permanent magnets.展开更多
7055 aluminum alloy plates with the same size were rolled by two processes： small percentage reduction per pass （PRPP） and large percentage reduction per pass, respectively. Meanwhile, the effect of PRPP on the pre...7055 aluminum alloy plates with the same size were rolled by two processes： small percentage reduction per pass （PRPP） and large percentage reduction per pass, respectively. Meanwhile, the effect of PRPP on the precipitates and corrosion resistance of 7055 aluminum alloy plate was investigated. The mechanisms were analyzed and discussed by optical microscopy （OM）, transmission electron microscopy （TEM）, high-resolution transmission electron microscopy （HRTEM） and electron back-scattered diffraction （EBSD） technique. Large PRPP can improve the corrosion resistance. For the plate rolled by small PRPP, the main precipitate is guinier-preston （GP） zone and continuous grain boundary precipitates （GBPs）, while, for the plate rolled by large PRPP, the main precipitates are the GP zone and η precipitate, and the GBPs are discontinuous.展开更多
SmCo_(5)alloy was prepared via direct calciothermic reduction using anhydrous samarium fluoride(SmF_(3))as raw material and cobalt as inducer.Results of the thermodynamic calculation show that the direct reduction of ...SmCo_(5)alloy was prepared via direct calciothermic reduction using anhydrous samarium fluoride(SmF_(3))as raw material and cobalt as inducer.Results of the thermodynamic calculation show that the direct reduction of cobalt-induced SmF_(3)for preparing SmCo_(5)alloy is feasible.An alloy with 33.89 wt%samarium and a yield of 96.45%were achieved under the optimal conditions of 10%and 20%excess of SmF_(3)and calcium over the stoichiometry,respectively,and 1450℃for 4 min.The X-ray diffraction results show that the reduction products are SmCo_(5)alloy and CaF_(2).The scanning electron microscopy micrograph of the SmCo_(5)alloy ingot exhibits a distinct dendritic morphology composed of samarium and cobalt.The X-ray photoelectron spectroscopy shows that the atomic ratio of samarium to cobalt is approximately 1:5 and both elements demonstrate zero valency(Sm^(0),Co^(0)).The magnetic properties measurement of the SmCo_(5)alloy melt-spun ribbon shows the remanent magnetization B_r=0.59 T,intrinsic coercivity H_(Ci)=345.82 kA/m and maximum magnetic energy density(BH)_(max)=42.20 kJ/m^(3).These results may be helpful for the development of novel valence-variable rare-earth alloys.展开更多
An attempt is made to measure three direction forces using octagonal ring dynamometer in the 2024 aluminum alloy friction stir joining(FSJ)process.A test is made to measure the specific area stress and stress distribu...An attempt is made to measure three direction forces using octagonal ring dynamometer in the 2024 aluminum alloy friction stir joining(FSJ)process.A test is made to measure the specific area stress and stress distributions in the specific area of the workpiece are obtained.The workpiece stresses in the FSJ process are analyzed by numerical simulation method.It is found that,in the downward stage of the process,feed force and lateral force in the tool are small,almost zero,and the maximum axial force can reach 12.5kN.In the stable joining stage,the forces acting on the tool become stabilized.Compared with the low speed,high feed speed results in small feed force and small lateral force,but large feed force in the stable joining stage.The stresses in three directions of feed direction,direction that perpendicular to butt face and direction perpendicular to the surface are obtained.The simulation stress value of measure point is obtained.Test and numerical simulation can authenticate each other.Both experimental stress values and numerical simulation stress values are credible.展开更多
AIM: To study changes produced within the inferior vena cava(IVC) during respiratory movements and identify their possible clinical implications.METHODS: This study included 100 patients(46 women; 54 men) over 18 year...AIM: To study changes produced within the inferior vena cava(IVC) during respiratory movements and identify their possible clinical implications.METHODS: This study included 100 patients(46 women; 54 men) over 18 years of age who required an abdominal computed tomography(CT) and central venous access. IVC cross-sectional areas were measured on CT scans at three levels, suprarenal(SR), juxtarenal(JR) and infrarenal(IR), during neutral breathing and again during the Valsalva maneuver. All patientswere instructed on how to perform a correct Valsalva maneuver. In order to reduce the total radiation dose in our patients, low-dose CT protocols were used in all patients. The venous blood pressure(systolic, diastolic and mean) was invasively measured at the same three levels with neutral breathing and the Valsalva maneuver during venous port implantation. From CT scans, threedimensional models of the IVC were constructed and a collapsibility index was calculated for each patient. These data were then correlated with venous pressures and cross-sectional areas.RESULTS: The mean patient age was 51.64 ± 12.01 years. The areas of the ellipse in neutral breathing were 394.49 ± 85.83(SR), 380.10 ± 74.55(JR), and 342.72 ± 49.77 mm2(IR), and 87.46 ± 18.35(SR), 92.64 ± 15.36(JR) and 70.05 ± 9.64 mm2(IR) during the Valsalva(P s < 0.001). There was a correlation between areas in neutral breathing and in the Valsalva maneuver(P < 0.05 in all areas). Large areas decreased more than smaller areas. The collapsibility indices were 0.49 ± 0.06(SR), 0.50 ± 0.04(JR) and 0.50 ± 0.04(IR), with no significant differences in any region. Reconstructed three-dimensional models showed a flattening of the IVC during Valsalva, adopting an ellipsoid cross-sectional shape. The mean pressures with neutral breathing were 9.44 ± 1.78(SR), 9.40 ± 1.44(JR) and 8.84 ± 1.03 mmHg(IR), and 81.08 ± 21.82(SR), 79.88 ± 19.01(JR) and 74.04 ± 16.56 mmHg(IR) during Valsalva(P s < 0.001). There was a negative correlation between cross-sectional caval area and venous blood pressure, but this was not statistically significant in any of the cases. There was a significant correlation between diastolic and mean pressures measured during neutral breathing and in Valsalva.CONCLUSION: Respiratory movements have a major influence on IVC dynamics. The increase in intracaval pressure during Valsalva results in a significant de-crease in the IVC cross-sectional area.展开更多
Shale gas, as an environmentally friendly fossil energy resource, has gained significant commercial development and shows immense potential. However, accurately predicting shale gas production faces substantial challe...Shale gas, as an environmentally friendly fossil energy resource, has gained significant commercial development and shows immense potential. However, accurately predicting shale gas production faces substantial challenges due to the complex law of decline, nonlinear and non-stationary features in production data, which greatly repair the robustness of current models in predicting shale gas production time series. To address these challenges and improve accuracy in production forecasting, this paper introduces a novel and innovative approach: a hybrid proxy model that combines the bidirectional long short-term memory(BiLSTM) neural network and random forest(RF) through deep learning. The BiLSTM neural network is adept at capturing long-term dependencies, making it suitable for understanding the intricate relationships between input and output variables in shale gas production.On the other hand, RF serves a dual purpose: reducing model variance and addressing the concept drift problem that arises in non-stationary time series predictions made by BiLSTM. By integrating these two models, the hybrid approach effectively captures the inherent dependencies present in long and nonstationary production time series, thereby reducing model uncertainty. Furthermore, the combination of BiLSTM and RF is optimized using the recently-proposed marine predators algorithm(MPA) to fine-tune hyperparameters and enhance the overall performance of the proxy model. The results demonstrate that the proposed BiLSTM-RF-MPA model achieves higher prediction accuracy and demonstrates stronger generalization capabilities by effectively handling the complex nonlinear and non-stationary characteristics of shale gas production time series. Compared to other models such as LSTM, BiLSTM, and RF, the proposed model exhibits superior fitting and prediction performance, with an average improvement in performance indicators exceeding 20%. This innovative framework provides valuable insights for forecasting the complex production performance of unconventional oil and gas reservoirs, which sheds light on the development of data-driven proxy models in the field of subsurface energy utilization.展开更多
The chemical composition and thermal properties of natural fibers are the most critical variables that determine the overall properties of the fibers and influence their processing and use in different sustainable app...The chemical composition and thermal properties of natural fibers are the most critical variables that determine the overall properties of the fibers and influence their processing and use in different sustainable applications,such as their conversion into bioenergy and biocomposites.Their thermal and mechanical properties can be estimated by evaluating the content of cellulose,lignin,and other extractives in the fibers.In this research work,the chemical composition and thermal properties of three fibers,namely bagasse,kenaf bast fibers,and cotton stalks,were evaluated to assess their potential utilization in producing biocomposites and bioenergy materials.The chemical composition analysis followed the Technical Association of the Pulp and Paper Industry Standards(TAPPI)methods.The total phenol content was quantified using the Folin-Ciocalteu method,while Fourier Transform Infrared Spectroscopy(FTIR)was employed to assess the light absorption by the bonds.To evaluate thermal stability and higher heating values,Thermogravimetric Analysis(TGA),Differential Scanning Calorimetry(DSC),and bomb calorimetry were performed.The chemical analysis revealed that bagasse contained 50.6%cellulose and 21.6%lignin,kenaf bast fibers had 58.5%cellulose and 10%lignin,and cotton stalks exhibited 40.3%cellulose and 21.3%lignin.The FTIR curves demonstrated a notable similarity among the fibers.The TGA analysis showed degradation temperatures of 321°C for bagasse,354°C for kenaf bast fibers,and 289°C for cotton stalks.The DSC analysis revealed glass transition temperatures of 81°C for bagasse,66.3°C for cotton stalks,and 64.5°C for kenaf bast fibers.The higher heating values were measured as 17.3,16.6 and 17.1 MJ/kg for bagasse,kenaf bast fibers,and cotton stalks,respectively.The three fibers have a high potential for biocomposites and bioenergy material manufacturing.展开更多
Sodium-ion batteries(SIBs)are considered as a promising candidate to replace lithium-ion batteries(LIBs)in large-scale energy storage applications.Abundant sodium resources and similar working principles make this tec...Sodium-ion batteries(SIBs)are considered as a promising candidate to replace lithium-ion batteries(LIBs)in large-scale energy storage applications.Abundant sodium resources and similar working principles make this technology attractive to be implemented in the near future.However,the development of high-performance carbon anodes is a focal point to the upcoming success of SIBs in terms of power density,cycling stability,and lifespan.Fundamental knowledge in electrochemical and physicochemical techniques is required to properly evaluate the anode performance and move it in the right direction.This review aims at providing a comprehensive guideline to help researchers from different backgrounds(e.g.,nanomaterials and thermochemistry)to delve into this topic.The main components,lab configurations,procedures,and working principles of SIBs are summarized.Moreover,a detailed description of the most used electrochemical and physicochemical techniques to characterize electrochemically active materials is provided.展开更多
The relationship between the water content or saturation of unsaturated soils and its matrix suction is commonly described by the soilwater characteristic curve(SWCC).Currently,study on the SWCC model is focused on fi...The relationship between the water content or saturation of unsaturated soils and its matrix suction is commonly described by the soilwater characteristic curve(SWCC).Currently,study on the SWCC model is focused on fine-grained soils like clay and silty soils,but the SWCC model for grinding soil-rock mixture(SRM)is less studied.Considering that the SRM is in a certain compaction state in the actual project,this study established a surface model with three variables of coupling compaction degree-substrate suction-moisture content based on the Cavalcante-Zornberg soil-water characteristic curve model.Then,the influence of each fitting parameter on the curve was analyzed.For the common SRM,the soil-water characteristic test was conducted.Moreover,the experimental measurements exhibit remarkable consistency with the mode surface.The analysis shows that the surface model intuitively describes the soil-water characteristics of grinding SRM,which can provide the SWCC of soils with bimodal pore characteristics under specific compaction degrees.Furthermore,it can reflect the influence of compaction degrees on the SWCC of rock-soil mass and has a certain prediction effect.The SWCC of SRM with various soil-rock ratios have a double-step shape.With the increase in compaction degree,the curves as a whole tend toward decreasing mass moisture content.The curve changes are mainly concentrated in the large pore section.展开更多
Tannin was extracted from different subspecies of Acacia nilotica,Acacia nilotica nilotica(Ann),Acacia nilotica tomentosa(Ant)and Acacia nilotica adansonii(Ana).The aim was to elucidate their structure and evaluate th...Tannin was extracted from different subspecies of Acacia nilotica,Acacia nilotica nilotica(Ann),Acacia nilotica tomentosa(Ant)and Acacia nilotica adansonii(Ana).The aim was to elucidate their structure and evaluate their reactivity as bioadhesives in the wood industry.The extracts were prepared by hot water extraction(90°C tem-perature).Their gel time with paraformaldehyde was used atfirst to compare their reactivity.The tannin contents and the percentage of total polyphenolic materials in different solutions of the extracts spray dried powder were determined by the hide powder method.Concentrated solutions(47%)were tested by both MALDI ToF,13CNMR.The thermomechanical analysis(TMA)was performed to evaluate their modulus of elasticity(MOE)at different pHs.The gel times of all the three tannin extracts showed that their reactivity and it was com-parable to other known procyanidin/prodelphinidin tannin extract types.Ana,Ann and Ant showed highest per-cent of total polyphenolic materials at 70%,64%,and 57%,respectively.The 13CNMR spectra showed that the three subspecies of condensed tannins were mainly constituted of procyanidins(PC)and prodelphinidins(PD)in slightly different ratios.Ann(56.5%PC and 43.4%PD),Ant(57%PC and 43%PD)and Ana(58%PC and 42%PD).MALDI–TOF spectra showed the presence offlavonoid monomers,and oligomers some of which linked to short carbohydrates monomers or dimers.TMA revealed that the three types of tannins had high MOE at their initial pH(5).展开更多
Describing the orientation state of the particles is often critical in fibre suspension applications.Macroscopic descriptors,the so-called second-order orientation tensor(or moment)leading the way,are often preferred ...Describing the orientation state of the particles is often critical in fibre suspension applications.Macroscopic descriptors,the so-called second-order orientation tensor(or moment)leading the way,are often preferred due to their low computational cost.Closure problems however arise when evolution equations for the moments are derived from the orientation distribution functions and the impact of the chosen closure is often unpredictable.In this work,our aim is to provide macroscopic simulations of orientation that are cheap,accurate and closure-free.To this end,we propose an innovative data-based approach to the upscaling of orientation kinematics in the context of fibre suspensions.Since the physics at the microscopic scale can be modelled reasonably enough,the idea is to conduct accurate offline direct numerical simulations at that scale and to extract the corresponding macroscopic descriptors in order to build a database of scenarios.During the online stage,the macroscopic descriptors can then be updated quickly by combining adequately the items from the database instead of relying on an imprecise macroscopic model.This methodology is presented in the well-known case of dilute fibre suspensions(where it can be compared against closure-based macroscopic models)and in the case of suspensions of confined or electrically-charged fibres,for which state-of-the-art closures proved to be inadequate or simply do not exist.展开更多
This paper concerns the real time control of the boundary layer on an aircraft wing. This new approach consists in heating the surface in an unsteady regime using electrically resistant strips embedded in the wing ski...This paper concerns the real time control of the boundary layer on an aircraft wing. This new approach consists in heating the surface in an unsteady regime using electrically resistant strips embedded in the wing skin. The control of the boundary layer＇s separation and transition point will provide a reduction in friction drag, and hence a reduction in fuel consumption. This new method consists in applying the required thermal power in the different strips in order to ensure the desired temperatures on the aircraft wing. We also have to determine the optimum size of these strips （length, width and distance between two strips）. This implies finding the best mathematical model corresponding to the physics enabling us to facilitate the calculation for any type of material used for the wings. Secondly, the heating being unsteady, and, as during a flight the flow conditions or the ambient temperatures vary, the thermal power needed changes and must be chosen as fast as possible in order to ensure optimal operating conditions.展开更多
MnNiGe：Fe ribbon samples are prepared. Partial Ni-and Mn-substitution of Fe element can both induce the antiferromagnetic-ferromagnetic conversion in the Ti Ni Si-type state of these MnNiGe：Fe ribbon systems. It is ...MnNiGe：Fe ribbon samples are prepared. Partial Ni-and Mn-substitution of Fe element can both induce the antiferromagnetic-ferromagnetic conversion in the Ti Ni Si-type state of these MnNiGe：Fe ribbon systems. It is found out, however, that some factors such as annealing, temperature variation process field-cycling, substituted site and magnetic field can affect the conversion and competition between the antiferromagnetic and ferromagnetic states in these ribbons. Therefore, in this paper these major influencing factors are studied systematically and further discussed are the related magnetic and magnetocaloric properties in MnNiGe：Fe ribbon systems.展开更多
This study proposes a novel approach to achieving highly reliable,low-voltage polarization switching of ferroelectric Hf_(0.5)Zr_(0.5)O_(2)(HZO)thin films using polymorph-and orientation-controlled W electrodes((111)-...This study proposes a novel approach to achieving highly reliable,low-voltage polarization switching of ferroelectric Hf_(0.5)Zr_(0.5)O_(2)(HZO)thin films using polymorph-and orientation-controlled W electrodes((111)-textured a-W and(200)-textured b-W)by adjusting the sputtering conditions.We demonstrated the formation of(111)and(002)/(020)-textured HZO films on the(111)-textured a-Wand(200)-textured b-W electrodes,respectively.Under a low-voltage pulse of 1.2 V(1.5 MV/cm),a-W/HZO/a-W and b-W/HZO/b-W capacitors exhibited double-remanent polarization(2Pr)values of 29.23 mC/cm^(2)and 25.16 mC/cm^(2),which were higher than that of the TiN/HZO/TiN capacitor by 33%and 14%,respectively,and a high endurance of 109 cycles without hard-breakdown.The differences in the ferroelectric properties and switching kinetics were understood based on the polymorphism and texture of the HZO films influenced by electrode materials.展开更多
The high energy density of green synthetic liquid chemicals and fuels makes them ideal for sustainable energy storage and transportation applications.Electroreduction of carbon dioxide(CO_(2))directly into such high v...The high energy density of green synthetic liquid chemicals and fuels makes them ideal for sustainable energy storage and transportation applications.Electroreduction of carbon dioxide(CO_(2))directly into such high value-added chemicals can help us achieve a renewable C cycle.Such electrochemical reduction typically suffers from low faradaic efficiencies(FEs)and generates a mixture of products due to the complexity of controlling the reaction selectivity.This perspective summarizes recent advances in the mechanistic understanding of CO_(2) reduction reaction pathways toward liquid products and the state-of-the-art catalytic materials for conversion of CO_(2) to liquid C1(e.g.,formic acid,methanol)and C2+products(e.g.,acetic acid,ethanol,n-propanol).Many liquid fuels are being produced with FEs between 80%and 100%.We discuss the use of structure-binding energy relationships,computational screening,and machine learning to identify promising candidates for experimental validation.Finally,we classify strategies for controlling catalyst selectivity and summarize breakthroughs,prospects,and challenges in electrocatalytic CO_(2) reduction to guide future developments.展开更多
文摘Penthorum chinense Pursh is rich in gallic acid, which has antioxidant, anti-inflammatory, anti-fungal and antitumor activities. In order to optimize their extraction conditions, various extraction parameters were chosen to identify their effects on gallic acid extraction. With extraction amount of gallic acid as index, based on single factor analysis, influence of solid/liquid ratio, ethanol concentration, fetch time and extraction temperature on extraction technology were investigated by orthogonal test. The optimization conditions for gallic acid extraction were determined as follows: ethanol concentration 60%, extraction time 2.5 h, temperature 90°C and solid/liquid ratio 1:30. The corresponding gallic acid content was 4.85%. This optimized extraction process was stable and feasible.
基金financially supported by the Program of Qingjiang Excellent Young Talents, Jiangxi University of Science and Technologythe Natural Science Foundation of Jiangxi Province (No. 20181BBE58001)the Natural Science Foundation of Jiangxi Education Department (No. GJJ180431)
文摘In this work, a green and effective corrosion inhibitor of functionalized carbon dots(FCDs) was synthesized by the conjugation of imidazole and citric acid carbon dots(CA-CDs). The corrosion inhibition behavior of FCDs for Q235 steel in 1 M HCl solution was systematically investigated by electrochemical analysis, corrosion morphology and adsorption isotherm. The electrochemical results implied that the as-prepared FCDs inhibitor could effectively suppress the corrosion of Q235 steel in 1 M HCl solution. At the same time, the inhibition efficiency of steel in 1 M HCl solution was more than 90% when the inhibitor concentration exceeded 100 mg/L. This excellent property was attributed to the coverage of adsorption film on the steel surface, which conformed to the Langmuir adsorption model. In addition, the analysis of adsorption isotherm displayed that the adsorption mechanism was the physicochemical interaction at the steel/solution interface.
基金Project supported by Program of National Natural Science Foundation of China(51604128)China Postdoctoral Science Foundation(2017M620279)Key projects of the major Research and Development Program of Jiangxi Province(20171ACE50008)
文摘The magnesium sulfate leaching technology for the ion-absorbed rare earths ore can solve the ammonia pollution problem existing in ammonium sulfate leaching process. However, the leaching capacity of magnesium sulfate is slightly weaker than that of ammonium sulfate, resulting in a bigger consumption of magnesium sulfate. In this paper, the MgSO4-ascorbic acid compound leaching agent had been demonstrated to deal with the ion-absorbed rare earths ore. The ascorbic acid could form a stable coordination with rare earth ions, so that it can strengthen the leaching of ion-exchangeable phase.Moreover, ascorbic acid has a strong reductive property, it can leach the colloidal sediment phase rare earth as well. The present study investigates the effect of the initial pH and the composition of leaching agent on the rare earth leaching. It is determined that the rare earth leaching efficiency is 107.5% under the condition of pH 2.00,0.15 mol/L magnesium sulfate and 1.0 g/L ascorbic acid in leaching agent. In this case, the content of the ion-exchangeable phase and colloidal sediment phase rare earth in the leaching residues are both only 0.02‰. The leaching efficiency of colloid sediment phase rare earth can be 85.7%,so that the Ce partition in the leaching liquor increases to be 5.77%. The magnesium-ascorbic acid compound leaching agent is proposed to be a promising choice to deal with the ion-absorbed rare earths ore, which can realize the efficient leaching, low consumption of MgSO4 and environmentally friendly leaching.
基金financially supported by the National Natural Science Foundation of China(Nos.51561008 and 51461017)Jiangxi Yorth Major Natural Science Foundation(Nos.20171ACB21044 and 20161BBE50030)
文摘The coarsening behavior of(Ni,Co)2Si particles in Cu-Ni-Co-Si alloy was investigated by experimental observations and coarsening kinetics calculations when aged at 450,500,550 and 600℃ for different durations.The results show that the critical particle radius for coherence mismatch is found to be 10.3 nm,and particles larger than 25 nm are generally semi-coherent.The relationship of(Ni,Co)2Si particles size and aging time follows Lifshitz,Slyosov and Wagner(LSW) theory.The particle size distributions fit well to the LSW theoretical distribution.The activation energy for(Ni,Co)2Si coarsening is accurately determined to be(216.21 ± 5.18)kJ mol-1 when considering the effect of temperature on the solution concentrations in matrix.The coarsening of(Ni,Co)2Si particles in Cu-Ni-Co-Si alloy is controlled by diffusion of Ni,Co and Si in Cu matrix.The growth of particles for long durations suggests that vacancies can be trapped within the structure for long time despite their mobility.
基金supported by the National Natural Science Foundation of China(Grant No.51271035 and U1560107)The financial support of the State Key Laboratory of Development and Application Technology of Automotive Steels
文摘The effects of Mn and Cr contents on bainitic transformation kinetics,microstructures and mechanical properties of high-carbon low alloy steels after austempered at 230,300 and 350 ℃ were determined by dilatometry,optical microscopy,scanning electron microscopy,X-ray diffraction and tensile tests. The results showed that Mn and Cr can extend bainitic incubation period and completion time,and with the increase of Mn and Cr content,the bainitic ferrite plate thickness decreased and the volume fraction of retained austenite increased. TRIP（ transformation induced plasticity） effect was observed during tensile testing which improved the overall mechanical property. The increase of Mn concentration can improve the strength to a certain extent,but reduce the ductility. The increase of Cr concentration can improve the ductility of bainitic steels which transformed at a low temperature. The low temperature bainitic steel austempered at 230 ℃ exhibited excellent mechanical properties with ultimate tensile strength of（ 2146 ± 11） MPa and total elongation of（ 12. 95 ± 0. 15） %.
基金financially supported by State High-Tech Development Plan (No. 2011AA061901)the TechnologyLanding Project of Jiangxi Province (No.KJLD13041)+1 种基金the Science and Technology Plan of Ganzhou (No.[2014]131)the Research Support Plan of Jiangxi University of Science and Technology(No. jxxjbs15001)
文摘Relationship between atomic local structures and Curie temperature of NdFeB permanent magnets was investigated semi-quantitatively using synchrotron radiation technique. Fe K-edge X-ray absorption spectroscopy(XAS) was employed to study the local structure of Fe atoms for samples before and after doping Dy, Tb or Gd. It is found that the bond lengths and coordination numbers are changed. Thus, the exchange interaction between Fe atoms increases with Dy, Tb or Gd doping, resulting in the improvement of Curie temperature of NdFeB permanent magnets. The doping effect is proven by experimental measurement of the magnetic properties. Microstructural characterization using scanning electron microscopy(SEM) was also used to further analyze the effect of different rare earth elements doping on Curie temperature of NdFeB permanent magnets.
基金financially supported by the Higher School Science Foundation of Inner Mongolia (No. NJZZ16082)National Natural Science Foundation of China (Nos. 51764043, 51461017 and 51364027)Science Program for Returned Chinese Scholars supported by Inner Mongolia and the Scientific and Technological Program of Innovation and Guidance of Inner Mongolia
文摘7055 aluminum alloy plates with the same size were rolled by two processes： small percentage reduction per pass （PRPP） and large percentage reduction per pass, respectively. Meanwhile, the effect of PRPP on the precipitates and corrosion resistance of 7055 aluminum alloy plate was investigated. The mechanisms were analyzed and discussed by optical microscopy （OM）, transmission electron microscopy （TEM）, high-resolution transmission electron microscopy （HRTEM） and electron back-scattered diffraction （EBSD） technique. Large PRPP can improve the corrosion resistance. For the plate rolled by small PRPP, the main precipitate is guinier-preston （GP） zone and continuous grain boundary precipitates （GBPs）, while, for the plate rolled by large PRPP, the main precipitates are the GP zone and η precipitate, and the GBPs are discontinuous.
基金Project supported by the National Natural Science Foundation of China(NSFC)(51774155)Jiangxi Provincial Key Research and Development Program(20192BBE50028)the Doctoral Scientific Research Foundation of Jiangxi University of Science and Technology(jxxjbs17077)。
文摘SmCo_(5)alloy was prepared via direct calciothermic reduction using anhydrous samarium fluoride(SmF_(3))as raw material and cobalt as inducer.Results of the thermodynamic calculation show that the direct reduction of cobalt-induced SmF_(3)for preparing SmCo_(5)alloy is feasible.An alloy with 33.89 wt%samarium and a yield of 96.45%were achieved under the optimal conditions of 10%and 20%excess of SmF_(3)and calcium over the stoichiometry,respectively,and 1450℃for 4 min.The X-ray diffraction results show that the reduction products are SmCo_(5)alloy and CaF_(2).The scanning electron microscopy micrograph of the SmCo_(5)alloy ingot exhibits a distinct dendritic morphology composed of samarium and cobalt.The X-ray photoelectron spectroscopy shows that the atomic ratio of samarium to cobalt is approximately 1:5 and both elements demonstrate zero valency(Sm^(0),Co^(0)).The magnetic properties measurement of the SmCo_(5)alloy melt-spun ribbon shows the remanent magnetization B_r=0.59 T,intrinsic coercivity H_(Ci)=345.82 kA/m and maximum magnetic energy density(BH)_(max)=42.20 kJ/m^(3).These results may be helpful for the development of novel valence-variable rare-earth alloys.
基金supported by the National Natural Science Foundation of China(51175255)the Funding of Jiangsu Innovation Program for Graduate Education(CXZZ13_0152)the Fundamental Research Funds for the Central Universities in P.R.China
文摘An attempt is made to measure three direction forces using octagonal ring dynamometer in the 2024 aluminum alloy friction stir joining(FSJ)process.A test is made to measure the specific area stress and stress distributions in the specific area of the workpiece are obtained.The workpiece stresses in the FSJ process are analyzed by numerical simulation method.It is found that,in the downward stage of the process,feed force and lateral force in the tool are small,almost zero,and the maximum axial force can reach 12.5kN.In the stable joining stage,the forces acting on the tool become stabilized.Compared with the low speed,high feed speed results in small feed force and small lateral force,but large feed force in the stable joining stage.The stresses in three directions of feed direction,direction that perpendicular to butt face and direction perpendicular to the surface are obtained.The simulation stress value of measure point is obtained.Test and numerical simulation can authenticate each other.Both experimental stress values and numerical simulation stress values are credible.
文摘AIM: To study changes produced within the inferior vena cava(IVC) during respiratory movements and identify their possible clinical implications.METHODS: This study included 100 patients(46 women; 54 men) over 18 years of age who required an abdominal computed tomography(CT) and central venous access. IVC cross-sectional areas were measured on CT scans at three levels, suprarenal(SR), juxtarenal(JR) and infrarenal(IR), during neutral breathing and again during the Valsalva maneuver. All patientswere instructed on how to perform a correct Valsalva maneuver. In order to reduce the total radiation dose in our patients, low-dose CT protocols were used in all patients. The venous blood pressure(systolic, diastolic and mean) was invasively measured at the same three levels with neutral breathing and the Valsalva maneuver during venous port implantation. From CT scans, threedimensional models of the IVC were constructed and a collapsibility index was calculated for each patient. These data were then correlated with venous pressures and cross-sectional areas.RESULTS: The mean patient age was 51.64 ± 12.01 years. The areas of the ellipse in neutral breathing were 394.49 ± 85.83(SR), 380.10 ± 74.55(JR), and 342.72 ± 49.77 mm2(IR), and 87.46 ± 18.35(SR), 92.64 ± 15.36(JR) and 70.05 ± 9.64 mm2(IR) during the Valsalva(P s < 0.001). There was a correlation between areas in neutral breathing and in the Valsalva maneuver(P < 0.05 in all areas). Large areas decreased more than smaller areas. The collapsibility indices were 0.49 ± 0.06(SR), 0.50 ± 0.04(JR) and 0.50 ± 0.04(IR), with no significant differences in any region. Reconstructed three-dimensional models showed a flattening of the IVC during Valsalva, adopting an ellipsoid cross-sectional shape. The mean pressures with neutral breathing were 9.44 ± 1.78(SR), 9.40 ± 1.44(JR) and 8.84 ± 1.03 mmHg(IR), and 81.08 ± 21.82(SR), 79.88 ± 19.01(JR) and 74.04 ± 16.56 mmHg(IR) during Valsalva(P s < 0.001). There was a negative correlation between cross-sectional caval area and venous blood pressure, but this was not statistically significant in any of the cases. There was a significant correlation between diastolic and mean pressures measured during neutral breathing and in Valsalva.CONCLUSION: Respiratory movements have a major influence on IVC dynamics. The increase in intracaval pressure during Valsalva results in a significant de-crease in the IVC cross-sectional area.
基金supported by Sichuan Natural Science Foundation (Grant No. 2023NSFSC0423)CNPC Innovation Found (Grant No. 2022DQ02-0207)+2 种基金Science and Technology Research Program of Chongqing Municipal Education Commission (KJQN202201510)supported by a grant from the Human Resources Development program (No. 20216110100070) of the Korea Institute of Energy Technology Evaluation and Planning (KETEP)funded by the Ministry of Trade, Industry, and Energy of the Korean Government。
文摘Shale gas, as an environmentally friendly fossil energy resource, has gained significant commercial development and shows immense potential. However, accurately predicting shale gas production faces substantial challenges due to the complex law of decline, nonlinear and non-stationary features in production data, which greatly repair the robustness of current models in predicting shale gas production time series. To address these challenges and improve accuracy in production forecasting, this paper introduces a novel and innovative approach: a hybrid proxy model that combines the bidirectional long short-term memory(BiLSTM) neural network and random forest(RF) through deep learning. The BiLSTM neural network is adept at capturing long-term dependencies, making it suitable for understanding the intricate relationships between input and output variables in shale gas production.On the other hand, RF serves a dual purpose: reducing model variance and addressing the concept drift problem that arises in non-stationary time series predictions made by BiLSTM. By integrating these two models, the hybrid approach effectively captures the inherent dependencies present in long and nonstationary production time series, thereby reducing model uncertainty. Furthermore, the combination of BiLSTM and RF is optimized using the recently-proposed marine predators algorithm(MPA) to fine-tune hyperparameters and enhance the overall performance of the proxy model. The results demonstrate that the proposed BiLSTM-RF-MPA model achieves higher prediction accuracy and demonstrates stronger generalization capabilities by effectively handling the complex nonlinear and non-stationary characteristics of shale gas production time series. Compared to other models such as LSTM, BiLSTM, and RF, the proposed model exhibits superior fitting and prediction performance, with an average improvement in performance indicators exceeding 20%. This innovative framework provides valuable insights for forecasting the complex production performance of unconventional oil and gas reservoirs, which sheds light on the development of data-driven proxy models in the field of subsurface energy utilization.
基金the Tenure Track Position“Bois:Biobased materials”part of E2S UPPA supported by the“Investissements d’Avenir”French Program managed by ANR(ANR-16-IDEX-0002).
文摘The chemical composition and thermal properties of natural fibers are the most critical variables that determine the overall properties of the fibers and influence their processing and use in different sustainable applications,such as their conversion into bioenergy and biocomposites.Their thermal and mechanical properties can be estimated by evaluating the content of cellulose,lignin,and other extractives in the fibers.In this research work,the chemical composition and thermal properties of three fibers,namely bagasse,kenaf bast fibers,and cotton stalks,were evaluated to assess their potential utilization in producing biocomposites and bioenergy materials.The chemical composition analysis followed the Technical Association of the Pulp and Paper Industry Standards(TAPPI)methods.The total phenol content was quantified using the Folin-Ciocalteu method,while Fourier Transform Infrared Spectroscopy(FTIR)was employed to assess the light absorption by the bonds.To evaluate thermal stability and higher heating values,Thermogravimetric Analysis(TGA),Differential Scanning Calorimetry(DSC),and bomb calorimetry were performed.The chemical analysis revealed that bagasse contained 50.6%cellulose and 21.6%lignin,kenaf bast fibers had 58.5%cellulose and 10%lignin,and cotton stalks exhibited 40.3%cellulose and 21.3%lignin.The FTIR curves demonstrated a notable similarity among the fibers.The TGA analysis showed degradation temperatures of 321°C for bagasse,354°C for kenaf bast fibers,and 289°C for cotton stalks.The DSC analysis revealed glass transition temperatures of 81°C for bagasse,66.3°C for cotton stalks,and 64.5°C for kenaf bast fibers.The higher heating values were measured as 17.3,16.6 and 17.1 MJ/kg for bagasse,kenaf bast fibers,and cotton stalks,respectively.The three fibers have a high potential for biocomposites and bioenergy material manufacturing.
基金part of the research project PID2019-107737RBI00funded by MCIN/AEI/10.13039/501100011033+2 种基金the funding from the Aragón Government(Ref.T22_(2)0R)funded by FEDER 2014-2020“Construyendo Europa desde Aragón”the funding from the Regional Government of Aragon(Spain)with a grant for postgraduate research contracts(2019-2023)。
文摘Sodium-ion batteries(SIBs)are considered as a promising candidate to replace lithium-ion batteries(LIBs)in large-scale energy storage applications.Abundant sodium resources and similar working principles make this technology attractive to be implemented in the near future.However,the development of high-performance carbon anodes is a focal point to the upcoming success of SIBs in terms of power density,cycling stability,and lifespan.Fundamental knowledge in electrochemical and physicochemical techniques is required to properly evaluate the anode performance and move it in the right direction.This review aims at providing a comprehensive guideline to help researchers from different backgrounds(e.g.,nanomaterials and thermochemistry)to delve into this topic.The main components,lab configurations,procedures,and working principles of SIBs are summarized.Moreover,a detailed description of the most used electrochemical and physicochemical techniques to characterize electrochemically active materials is provided.
基金funded by the Science and Technology Research Program of Chongqing Municipal Education Commission(grant number KJZD-K202100705)the Talents Program Supply System of Chongqing(grant number cstc2022ycjhbgzxm0080)。
文摘The relationship between the water content or saturation of unsaturated soils and its matrix suction is commonly described by the soilwater characteristic curve(SWCC).Currently,study on the SWCC model is focused on fine-grained soils like clay and silty soils,but the SWCC model for grinding soil-rock mixture(SRM)is less studied.Considering that the SRM is in a certain compaction state in the actual project,this study established a surface model with three variables of coupling compaction degree-substrate suction-moisture content based on the Cavalcante-Zornberg soil-water characteristic curve model.Then,the influence of each fitting parameter on the curve was analyzed.For the common SRM,the soil-water characteristic test was conducted.Moreover,the experimental measurements exhibit remarkable consistency with the mode surface.The analysis shows that the surface model intuitively describes the soil-water characteristics of grinding SRM,which can provide the SWCC of soils with bimodal pore characteristics under specific compaction degrees.Furthermore,it can reflect the influence of compaction degrees on the SWCC of rock-soil mass and has a certain prediction effect.The SWCC of SRM with various soil-rock ratios have a double-step shape.With the increase in compaction degree,the curves as a whole tend toward decreasing mass moisture content.The curve changes are mainly concentrated in the large pore section.
基金the fund provided by NAPATA program,jointly funded by France campus and the Ministry of Higher Education and Scientific research,SudanLab facilities provided by LERMAB which is supported by a grant of the French Agence Nationale de la Recherche(ANR)in the ambit of the laboratory of excellence(Labex)ARBRE is also aknowledged.
文摘Tannin was extracted from different subspecies of Acacia nilotica,Acacia nilotica nilotica(Ann),Acacia nilotica tomentosa(Ant)and Acacia nilotica adansonii(Ana).The aim was to elucidate their structure and evaluate their reactivity as bioadhesives in the wood industry.The extracts were prepared by hot water extraction(90°C tem-perature).Their gel time with paraformaldehyde was used atfirst to compare their reactivity.The tannin contents and the percentage of total polyphenolic materials in different solutions of the extracts spray dried powder were determined by the hide powder method.Concentrated solutions(47%)were tested by both MALDI ToF,13CNMR.The thermomechanical analysis(TMA)was performed to evaluate their modulus of elasticity(MOE)at different pHs.The gel times of all the three tannin extracts showed that their reactivity and it was com-parable to other known procyanidin/prodelphinidin tannin extract types.Ana,Ann and Ant showed highest per-cent of total polyphenolic materials at 70%,64%,and 57%,respectively.The 13CNMR spectra showed that the three subspecies of condensed tannins were mainly constituted of procyanidins(PC)and prodelphinidins(PD)in slightly different ratios.Ann(56.5%PC and 43.4%PD),Ant(57%PC and 43%PD)and Ana(58%PC and 42%PD).MALDI–TOF spectra showed the presence offlavonoid monomers,and oligomers some of which linked to short carbohydrates monomers or dimers.TMA revealed that the three types of tannins had high MOE at their initial pH(5).
文摘Describing the orientation state of the particles is often critical in fibre suspension applications.Macroscopic descriptors,the so-called second-order orientation tensor(or moment)leading the way,are often preferred due to their low computational cost.Closure problems however arise when evolution equations for the moments are derived from the orientation distribution functions and the impact of the chosen closure is often unpredictable.In this work,our aim is to provide macroscopic simulations of orientation that are cheap,accurate and closure-free.To this end,we propose an innovative data-based approach to the upscaling of orientation kinematics in the context of fibre suspensions.Since the physics at the microscopic scale can be modelled reasonably enough,the idea is to conduct accurate offline direct numerical simulations at that scale and to extract the corresponding macroscopic descriptors in order to build a database of scenarios.During the online stage,the macroscopic descriptors can then be updated quickly by combining adequately the items from the database instead of relying on an imprecise macroscopic model.This methodology is presented in the well-known case of dilute fibre suspensions(where it can be compared against closure-based macroscopic models)and in the case of suspensions of confined or electrically-charged fibres,for which state-of-the-art closures proved to be inadequate or simply do not exist.
文摘This paper concerns the real time control of the boundary layer on an aircraft wing. This new approach consists in heating the surface in an unsteady regime using electrically resistant strips embedded in the wing skin. The control of the boundary layer＇s separation and transition point will provide a reduction in friction drag, and hence a reduction in fuel consumption. This new method consists in applying the required thermal power in the different strips in order to ensure the desired temperatures on the aircraft wing. We also have to determine the optimum size of these strips （length, width and distance between two strips）. This implies finding the best mathematical model corresponding to the physics enabling us to facilitate the calculation for any type of material used for the wings. Secondly, the heating being unsteady, and, as during a flight the flow conditions or the ambient temperatures vary, the thermal power needed changes and must be chosen as fast as possible in order to ensure optimal operating conditions.
基金the National Natural Science Foundation of China (Grant Nos. 51261022, 51561023 and 51671097)the Jiangxi Provincial Graduate Student Innovation Special Funds Project (Grant No. YC2015-S310)the Graduate Student Innovation Special Funds Project of Nanchang Hangkong University (Grant No. YC2015007)
文摘MnNiGe：Fe ribbon samples are prepared. Partial Ni-and Mn-substitution of Fe element can both induce the antiferromagnetic-ferromagnetic conversion in the Ti Ni Si-type state of these MnNiGe：Fe ribbon systems. It is found out, however, that some factors such as annealing, temperature variation process field-cycling, substituted site and magnetic field can affect the conversion and competition between the antiferromagnetic and ferromagnetic states in these ribbons. Therefore, in this paper these major influencing factors are studied systematically and further discussed are the related magnetic and magnetocaloric properties in MnNiGe：Fe ribbon systems.
基金supported by the National Research Foundation of Korea,funded by the Ministry of Science and ICT(RS-2024-00445552)(50%)supported by the Nano&Material Technology Development Program through the National Research Foundation of Korea(NRF)funded by Ministry of Science and ICT(RS-2024-00444182)(50%).
文摘This study proposes a novel approach to achieving highly reliable,low-voltage polarization switching of ferroelectric Hf_(0.5)Zr_(0.5)O_(2)(HZO)thin films using polymorph-and orientation-controlled W electrodes((111)-textured a-W and(200)-textured b-W)by adjusting the sputtering conditions.We demonstrated the formation of(111)and(002)/(020)-textured HZO films on the(111)-textured a-Wand(200)-textured b-W electrodes,respectively.Under a low-voltage pulse of 1.2 V(1.5 MV/cm),a-W/HZO/a-W and b-W/HZO/b-W capacitors exhibited double-remanent polarization(2Pr)values of 29.23 mC/cm^(2)and 25.16 mC/cm^(2),which were higher than that of the TiN/HZO/TiN capacitor by 33%and 14%,respectively,and a high endurance of 109 cycles without hard-breakdown.The differences in the ferroelectric properties and switching kinetics were understood based on the polymorphism and texture of the HZO films influenced by electrode materials.
基金supported by the Joint Funds of the National Natural Science Foundation of China(U24B20201)National Natural Science Foundation of China(22372007 and 21972010)+1 种基金the Fundamental Research Funds for the Central Universities(JD2427)the SRC Center for Electron Transfer(2021R1A5A1030054)funded by NRF Korea and AI Graduate School Program(RS-2021-II211343).
文摘The high energy density of green synthetic liquid chemicals and fuels makes them ideal for sustainable energy storage and transportation applications.Electroreduction of carbon dioxide(CO_(2))directly into such high value-added chemicals can help us achieve a renewable C cycle.Such electrochemical reduction typically suffers from low faradaic efficiencies(FEs)and generates a mixture of products due to the complexity of controlling the reaction selectivity.This perspective summarizes recent advances in the mechanistic understanding of CO_(2) reduction reaction pathways toward liquid products and the state-of-the-art catalytic materials for conversion of CO_(2) to liquid C1(e.g.,formic acid,methanol)and C2+products(e.g.,acetic acid,ethanol,n-propanol).Many liquid fuels are being produced with FEs between 80%and 100%.We discuss the use of structure-binding energy relationships,computational screening,and machine learning to identify promising candidates for experimental validation.Finally,we classify strategies for controlling catalyst selectivity and summarize breakthroughs,prospects,and challenges in electrocatalytic CO_(2) reduction to guide future developments.
