The electrocatalytic reduction of CO_(2)is a promising pathway to generate renewable fuels and ***,its advancement is impeded by the absence of electrocatalysts with both high selectivity and ***,we present a scalable...
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The electrocatalytic reduction of CO_(2)is a promising pathway to generate renewable fuels and ***,its advancement is impeded by the absence of electrocatalysts with both high selectivity and ***,we present a scalable in-situ thermal evaporation technique for synthesizing series of Bi,In,and Sn nanofilms on carbon felt(CF)substrates with a high-aspect-ratio *** resulting main-group metal nanofilms exhibit a homogeneously distributed and highly exposed catalyst surface with ample active sites,thereby promoting mass transport and ad-/desorption of reaction *** from the unique fractal morphology,the Bi nanofilms deposited on CF exhibit optimal catalytic activities for CO_(2)electroreduction among the designed metal nanofilms electrodes,with the highest Faradaic efficiency of 96.9%for formate production at−1.3 V *** hydrogen electrode(RHE)in *** an industrially relevant current density of 221.4 mA·cm−2 in flow cells,the Bi nanofilms retain a high Faradaic efficiency of 81.7%at−1.1 V(***)and a good long-term stability for formate ***,a techno-economic analysis(TEA)model shows the potential commercial viability of electrocatalytic CO_(2)conversion into formate using the Bi nanofilms *** results offer a green and convenient approach for in-situ fabrication of stable and inexpensive thin-film catalysts with a fractal structure applicable to various industrial settings.
The mechanical and thermodynamic properties of W-Ti alloys(including W_(15)Ti_(1),W_(14)Ti_(2),W_(12)Ti_(4) and W_(8)Ti_(8) alloys)were investigated by the first-principles approach based on density functional *** res...
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The mechanical and thermodynamic properties of W-Ti alloys(including W_(15)Ti_(1),W_(14)Ti_(2),W_(12)Ti_(4) and W_(8)Ti_(8) alloys)were investigated by the first-principles approach based on density functional *** results indicate that W-Ti alloys except W_(8)Ti_(8) are thermodynamically *** modulus and hardness of W-Ti alloys are smaller than those of pure tungsten and gradually decrease with increasing Ti ***,their B/G ratios and Poisson's ratios exceed those of pure tungsten,suggesting that the introduction of Ti decreases the mechanical strength while enhancing the ductility of W-Ti *** thermal expansion coefficients for W-Ti alloys all surpass those of pure tungsten,indicating that the introduction of titanium exacerbates the thermal expansion behavior of W-Ti ***,elevated pressure has the capacity to suppress the thermal expansion tendencies in titanium-doped tungsten *** study offers theoretical insights for the design of nuclear materials by exploring the mechanical and thermodynamic properties of W-Ti alloys.
The piezoelectric strain of K_(0.5)Na_(0.5)NbO_(3)-based lead-free ceramic at different temperatures was *** Rayleigh analysis shows that the intrinsic and extrinsic contributions are increased at temperature from 173...
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The piezoelectric strain of K_(0.5)Na_(0.5)NbO_(3)-based lead-free ceramic at different temperatures was *** Rayleigh analysis shows that the intrinsic and extrinsic contributions are increased at temperature from 173 to 298 *** addition,a monoclinic phase structure was observed at 83 *** results of phase field simulation show that the temperature dependent microstructure evolution is a function of the local structure *** work contributes to understanding the structure and properties relationship of the multi-cations doped KNN-based piezoelectric ceramics as a function of temperature.
Inspired by structures of natural shells,zirconia-carbon nanocomposites were obtained by using natural chitin from shrimp shells as templates via the sol-gel route in this *** was dispersed in the water and chelated w...
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Inspired by structures of natural shells,zirconia-carbon nanocomposites were obtained by using natural chitin from shrimp shells as templates via the sol-gel route in this *** was dispersed in the water and chelated with the zirconia precursors by *** a heat treatment for carbonization,nacre-like structures of carbon-zirconia nanocomposites were successfully *** to the toughening mechanism of tetragonal zirconia,the mechanical properties of carbon-zirconia composites are further *** as-received zirconia/carbon nanocomposite with best mechanical property has a hardness of 5.88GPa and an elastic modulus of 80.6 GPa,which is even stronger than natural *** work might facilitate a versatile platform for developing green nanocomposites with reasonably good mechanical properties.
High resolution and full-color light-emitting diodes require precise and efficient patterning of light-emitting structures containing quantum dots or *** report light-induced inverted patterning of nanocrystals in gla...
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High resolution and full-color light-emitting diodes require precise and efficient patterning of light-emitting structures containing quantum dots or *** report light-induced inverted patterning of nanocrystals in glasses for micro-light-emitting *** laser pulse induces structural destruction and amorphization of nanocrystals in glasses,forming inverted luminescent ***-throughput patterning of micrometer-scale,thermally stable,and highly photoluminescent structures in nanocrystals embedded glass is *** patterning method provides a novel way to fabricate high-performance and ultrahigh-resolution color conversion layers for micrometer-scale light-emitting diodes.
Ga-doped Li_(7)La_(3)Zr_(2)O_(12)(Ga-LLZO)has long been considered as a promising garnet-type electrolyte candidate for all-solid-state lithium metal batteries(ASSLBs)due to its high room temperature ionic ***,the typ...
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Ga-doped Li_(7)La_(3)Zr_(2)O_(12)(Ga-LLZO)has long been considered as a promising garnet-type electrolyte candidate for all-solid-state lithium metal batteries(ASSLBs)due to its high room temperature ionic ***,the typical synthesis of Ga-LLZO is usually accompanied by the formation of undesired LiGaO_(2) impurity phase that causes severe instability of the electrolyte in contact with molten Li metal during half/full cell *** this study,we show that by simply engineering the defect chemistry of Ga-LLZO,namely,the lithium deficiency level,LiGaO_(2) impurity phase is effectively inhibited in the final synthetic ***,defect chemistry engineered Ga-LLZO exhibits excellent electrochemical stability against lithium metal,while its high room temperature ionic conductivity(~1.9×10^(-3)S·cm^(-1))is well *** assembled Li/Ga-LLZO/Li symmetric cell has a superior critical current density of 0.9 mA·cm^(-2),and cycles stably for 500 hours at a current density of 0.3 mA·cm^(-2).This research facilitates the potential commercial applications of high performance Ga-LLZO solid electrolytes in ASSLBs.
In order to improve efficiency and reduce costs, four machine learning models were established for the design of metastable β titanium alloys, including the Adaboost model, the LightGBM model, the Voting model, and t...
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In order to improve efficiency and reduce costs, four machine learning models were established for the design of metastable β titanium alloys, including the Adaboost model, the LightGBM model, the Voting model, and the Stacking model. The accuracy of these models was evaluated, and all models exhibited excellent accuracy for tensile strength, yield strength, and elongation. The values of R-squared coefficients(R2) all greater than *** them, the LightGBM model showed the highest accuracy, with relatively smallest values of mean absolute error(MAE) and root mean square error(RMSE) and relatively largest value of R2. To further verify the accuracy of the model, a metastable β titanium alloy Ti-5.5Cr-5Al-4Mo-3Nb-2Zr was designed by the LightGBM model. The predicted values of the alloy's tensile strength, yield strength, and elongation under three heat treatment processes were in high agreement with the experimental values. The alloy exhibited optimal strength-plasticity matching after undergoing a solution treatment at 850°C for 0.5 h, followed by aging at 650°C for 8 h, with a tensile strength of 1317 MPa, an elongation of 11.17 %, and a strength-plasticity product of 14.711 GPa·%.
Seawater electrolysis is a highly promising method to produce high energy density hydrogen,especially in dry areas that have scarce freshwater ***,application of seawater electrolysis is confronted by two major proble...
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Seawater electrolysis is a highly promising method to produce high energy density hydrogen,especially in dry areas that have scarce freshwater ***,application of seawater electrolysis is confronted by two major problems associated with catalysts employed for the anodic oxygen evolution reaction(OER) including the competitive hypochlorite evolution reaction(HCER) and strong chloridion(Cl-) triggered *** studies aimed at overcoming these problems,a facile method has been developed to synthesize a homologous CoS2heterojunction as an OER *** to a difference in work functions at the interface and increased electron density,this material has directed electron transfer and strong chloridion repulsion properties,*** have shown that CoS2achieves low overpotentials of 289 and 322 mV at 10 mA cm-2current density in respective alkaline(1 M KOH) and alkaline simulated seawater ***,the outstanding stability of CoS2is reflected in a negligible decline in activity during promotion of the OER for 100 *** of density functional theory calculations reveal that the homologous CoS2heterojunction promotes directed electron transport for optimizing adsorption/desorption of reactive species and heightens the Cl-adsorption energy for strongly repulsing Cl-,phenomena that enhance OER performance in alkaline simulated seawater.
Due to its low cost and natural abundance of sodium,Na-ion batteries(NIBs)are promising candidates for large-scale energy storage *** development of ultralow voltage anode materials is of great significance in improvi...
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Due to its low cost and natural abundance of sodium,Na-ion batteries(NIBs)are promising candidates for large-scale energy storage *** development of ultralow voltage anode materials is of great significance in improving the energy density of ***-voltage anode materials,however,are severely lacking in *** all the reported insertion oxides anodes,the Na_(2)Ti_(3)O_(7) has the lowest operating voltage(an average potential of 0.3 V ***^(+)/Na)and is less likely to deposit sodium,which has excellent potential for achieving NIBs with high energy densities and high *** significant progress has been made,achieving Na_(2)Ti_(3)O_(7) electrodes with excellent performance remains a severe *** paper systematically summarizes and discusses the physicochemical properties and synthesis methods of Na_(2)Ti_(3)O_(7).Then,the sodium storage mechanisms,key issues and challenges,and the optimization strategies for the electrochemical performance of Na_(2)Ti_(3)O_(7) are classified and further ***,remaining challenges and future research directions on the Na_(2)Ti_(3)O_(7) anode are *** review offers insights into the design of high-energy and high-safety NIBs.
A numerical method to predict the bursting strength of filament wound composite rocket motor case is proposed *** method can evaluate the longitudinal stress evolution of each composite layer as impregnated filaments ...
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A numerical method to predict the bursting strength of filament wound composite rocket motor case is proposed *** method can evaluate the longitudinal stress evolution of each composite layer as impregnated filaments with fiber tension are wound layer by layer,and consider the effects of accumulated stress and deformation during filament winding on the bursting strength of composite ***∅520 mm composite cases as a case study,the filament-winding-process-induced stress and deformation as well as progressive damage behavior are numerically predicted,followed by a comparison with experimental *** numerical results show that the predicted bursting pressures for composite cases manufactured on the mandrels with and without a flexible component are 14.20 MPa and 21.40 MPa,*** values exhibit slight deviation from the measured pressures of 13.50 MPa and 21.57 ***,the predicted damage locations,situated respectively in the dome and cylinder,agree well with the experimental *** observations indicate that use of flexible component reduces the load-bearing capacity of the ***,it validates the reliability and accuracy of the proposed numerical method in predicting the bursting strength of composite cases.
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