The stability and uniformity of solid electrolyte interphase(SEI)are critical for clarifying the origin of capacity fade and safety issues for lithium metal anodes(LMA).However,understanding the interplay of SEI heter...
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The stability and uniformity of solid electrolyte interphase(SEI)are critical for clarifying the origin of capacity fade and safety issues for lithium metal anodes(LMA).However,understanding the interplay of SEI heterogeneity and Li electrodeposition is limited by the coupling of complex electrochemistry and mechanics ***,the correlation between the SEI failure behavior and Li deposition morphology is investigated through a quantitative electrochemical-mechanical *** local deformation and stress of SEI during Li electrodeposition identify that the heterogeneous interface between different components first *** with the well-known mechanical strength,component uniformity plays the most important role in the initial SEI failure and uneven Li deposition,and a relative component uniformity(p>0.01)represents a proper balance to ensure the stability of the naturally heterogeneous ***,the component regulation of SEI via the designed electrolyte experimentally demonstrates that improving component uniformity benefits SEI stability and the uniform Li electrodeposition for LMA,thereby increasing the capacity by~20%after 300 *** fundamental understandings and proposed strategy can be not only used to guide the SEI optimization via the electrolyte regulation,but also extended to the rational designs of artificial SEI for high-performance LMA.
Composites featuring negative permittivity have garnered significant attention for their potential in novel capacitance designs,coil-less electrical inductors,and electromagnetic shielding *** this study,we prepared p...
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Composites featuring negative permittivity have garnered significant attention for their potential in novel capacitance designs,coil-less electrical inductors,and electromagnetic shielding *** this study,we prepared polyvinylidene fluoride(PVDF)matrix composites filled with ZrO_(2)/C nanoparticles de-rived from metal-organic frameworks(MOFs)via a hot-pressing *** an increase in the ZrO_(2)/C content to 30 wt.%,electrical percolation was observed,accompanied by a transition mechanism from hopping conduction to metal-like *** enabled the realization of ZrO_(2)/C/PVDF composites with tailorable negative permittivity properties,attributed to the plasmonic oscillation of free electrons in the composites beyond the percolation threshold(30 wt.%).Furthermore,the permittivity transition along to a shift in the electrical behavior of the percolative composites from capacitive to *** explored the regulatory mechanism behind the negative permittivity in this random composite system,and our findings highlight the potential of these tunable negative permittivity media as promising candi-dates for diverse electromagnetic applications.
The electronegative filling in skutterudites not only broadened the scope of filling atoms,but also facilitated the preparation of p-type ***,the introduction of a single sulfur atom in the Co_(4)Sb_(12) cannot be ach...
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The electronegative filling in skutterudites not only broadened the scope of filling atoms,but also facilitated the preparation of p-type ***,the introduction of a single sulfur atom in the Co_(4)Sb_(12) cannot be achieved without charge compensation through the traditional equilibrium *** the present study,the dual occupations of S-atoms by self-charge compensation were shown as the most stable forms under high pressure,and a series of p-type S_(y)Co_(4)Sb_(12-2y)S_(2y) skutterudites was successfully prepared by high-pressure-high-temperature(HPHT)*** electronic structures and transport properties of as-obtained materials were investigated,and the related mechanisms were *** results suggested that the presence of S-impurities led to flattening of the electronic band that led to a higher Seebeck *** S-doped Co_(4)Sb_(12) displayed lower elastic modulus,elastic constant,and Debye temperature,thus indicating the chemical bond softening in *** thermal conductivities of S_(y)Co_(4)Sb_(12-2y)S_(2y) compounds reduced monotonously with the increase in *** study provides a new and promising avenue for optimizing the thermoelectric properties of p-type Co_(4)Sb_(12).
Casting process numerical simulation can predict casting defects and performance, improving the efficiency of casting product process design and optimization. However, the accuracy of casting process numerical simulat...
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Plastics,fibers and rubber are three mainstream synthetic materials that are essential to our daily lives and contribute significantly to the quality of our *** production of the monomers of these synthetic polymers u...
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Plastics,fibers and rubber are three mainstream synthetic materials that are essential to our daily lives and contribute significantly to the quality of our *** production of the monomers of these synthetic polymers usually involves oxidation or ammoximation reactions of olefins and ***,the utilization of C,O and N atoms in current industrial processes is <80%,which represents the most environmentally polluting processes for the production of basic *** innovation and integration of catalytic materials,new reaction pathways,and reaction engineering,the Research Institute of Petroleum processing,Sinopec Co.,Ltd.(RIPP) and its collaborators have developed unique H2O2-centered oxidation/ammoximation technologies for olefins and analogues,which has resulted in a ¥500 billion emerging industry and driven trillions of ¥s' worth of downstream *** chemical and engineering bases of the production technologies mainly involve the integration of slurry-bed reactors and microsphere catalysts to enhance H2O2production,H2O2propylene/chloropropylene epoxidation for the production of propylene oxide/epichlorohydrin,and integration of H2O2cyclohexanone ammoximation and membrane separation to innovate the caprolactam production *** review briefly summarizes the whole process from the acquisition of scientific knowledge to the formation of an industrial production technology by ***,the scientific frontiers of H2O2production and related oxidation/ammoximation processes of olefins and analogues are reviewed,and new technological growth points are envisaged,with the aim of maintaining China's standing as a leader in the development of the science and technologies of H2O2production and utilization.
The two-dimensional X-ray inspection images of light alloy castings cannot intuitively reflect the depth and size of defects, and the correspondence between image defect coordinates and the three-dimensional body of t...
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The automatic defect detection of casting X-ray inspection images based on deep learning has the problems of single defect sample topography and poor network generalization. Therefore, the research on casting inspecti...
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Increasing environmental pollution and shortage of conventional fossil fuels have made it urgent to develop renewable and clean energy sources. Electrocatalytic water splitting, with its abundant raw materials, simple...
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Increasing environmental pollution and shortage of conventional fossil fuels have made it urgent to develop renewable and clean energy sources. Electrocatalytic water splitting, with its abundant raw materials, simple process, and zero carbon emission, is considered one of the most promising processes for producing carbon-neutral hydrogen which has excellent energy conversion efficiency and high gravimetric energy density. Among them, oxygen evolution reaction (OER) electrocatalysts and hydrogen evolution reaction (HER) electrocatalysts are critical to decreasing the intrinsic reaction energy barrier and boosting the hydrogen evolution efficiency. Therefore, it is imperative to develop and design low-cost, highly active, and stable OER and HER electrocatalysts to lower the overpotential and drive the electrocatalytic reactions. Transition metal sulfides, especially iron-based sulfides, have attracted extensive exploration by researchers as a result of its high abundance in the Earth's crust and near-metallic conductivity. Consequently, in this review, we systematically and comprehensively summarize the progress in the application of iron-based sulfides and their composites as OER and HER electrocatalysts in electrocatalysis. Detailed descriptions and illustrations of the special relationships among their composition, structure, and electrocatalytic performance are presented. Finally, this review points out the challenges and future prospects of iron-based sulfides in practical applications for designing and fabricating more promising iron-based sulfide OER and HER electrocatalysts. We believe that iron-based sulfide materials will have a wide range of application prospects as OER and HER electrocatalysts in the future.
The feeding system can effectively reduce the shrinkage porosity in the design of casting process and then improve the casting quality and process yield. therefore, the automatic and intelligent design of the feeding ...
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Complex castings of light alloys such as aluminum, titanium and magnesium are widely used in high-end national defense equipment such as aerospace. The main means of internal defect detection are "X-ray flaw dete...
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