The electrochemical mechanism of nanocrystalline silicon anode in sodium ion batteries is first studied via in operando Raman and in operando X‐ray diffraction. An irreversible structural conversion ...from crystalline silicon to amorphous silicon takes place during the initial cycles, leading to ultrafast reversible sodium insertion in the newly generated amorphous silicon. Furthermore, an optimized silicon/carbon composite has been developed to further improve its electrochemical performance.
Normal decane was selected as a surrogate fuel for RP-3 aviation fuel, and soot formation characteristics and effects of n-decane (D) /n-butanol (B) cofiring were investigated experimentally and ...numerically. Combustion experiments of six n-decane/n-butanol blends (i.e., D100, D80, D60, D40, D20, D00, indicating the volumetric fraction of n-butanol in blends) were performed on co-flow diffusion flames. The volume fraction and morphological characteristics of soot at different heights of the flame axis were obtained using thermophoretic sampling and transmission electron microscopy analysis. A newly developed n-decane/n-butanol/PAH kinetic model consisted of 73 species and 275 reactions were further applied to model the soot formation process and ascertain the effects of n-butanol blending. Experimental and simulation results showed that soot loading (soot volume fraction and number density) decreased with increasing n-butanol blending ratios. Chemical kinetic analysis suggested that n-butanol addition decreased the rate of the HACA reaction as a result of a reduction of C2H2 and C2H3 (+M) ⇄ C2H2 + H (+M), ultimately leading to a reduction of soot loading.
The maize inbred line A188 is an attractive model for elucidation of gene function and improvement due to its high embryogenic capacity and many contrasting traits to the first maize reference ...genome, B73, and other elite lines. The lack of a genome assembly of A188 limits its use as a model for functional studies.
Here, we present a chromosome-level genome assembly of A188 using long reads and optical maps. Comparison of A188 with B73 using both whole-genome alignments and read depths from sequencing reads identify approximately 1.1 Gb of syntenic sequences as well as extensive structural variation, including a 1.8-Mb duplication containing the Gametophyte factor1 locus for unilateral cross-incompatibility, and six inversions of 0.7 Mb or greater. Increased copy number of carotenoid cleavage dioxygenase 1 (ccd1) in A188 is associated with elevated expression during seed development. High ccd1 expression in seeds together with low expression of yellow endosperm 1 (y1) reduces carotenoid accumulation, accounting for the white seed phenotype of A188. Furthermore, transcriptome and epigenome analyses reveal enhanced expression of defense pathways and altered DNA methylation patterns of the embryonic callus.
The A188 genome assembly provides a high-resolution sequence for a complex genome species and a foundational resource for analyses of genome variation and gene function in maize. The genome, in comparison to B73, contains extensive intra-species structural variations and other genetic differences. Expression and network analyses identify discrete profiles for embryonic callus and other tissues.
The primary aim of this work was to synthesize aligned perchloric‐acid‐doped poly(aniline) (HClO4‐doped PANI) nanotubes by a simple alumina template method and to investigate their application in ...lithium/poly(aniline) rechargeable batteries. Powder X‐ray diffraction analysis (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Fourier transform infrared (FTIR) analysis were used to characterize the nanostructures obtained. The second aim addressed the preparation of HClO4‐doped PANI microspheres and nanofibers on a large scale through a modified spraying technique, since the template synthesis has limitations in mass production. The present synthesis methods are simple and can be extended to the preparation of a broad range of one‐dimensional conductive polymers. Furthermore, electrochemical measurements showed that the as‐prepared HClO4‐doped PANI nanotubes exhibit better electrode performances than their commercial counterparts because they possess more active sites, higher conductivity, and relative flexibility. This indicates that HClO4‐doped poly(aniline) nanomaterials are promising in the application of lithium/polymer rechargeable batteries.
Controlled synthesis and application: Poly(aniline) nanotubes and nanofibers doped with perchloric acid (see picture) have been selectively synthesized and characterized. The highly aligned polymer nanotubes show increased conductivity and exhibit enhanced electrochemical performance in lithium/poly(aniline) rechargeable batteries compared to their commercial powder counterparts.
Sodium metal anode is considered the most promising alternative to lithium due to its cost‐effectiveness and widespread availability. To realize its practical applications, numerous strategies have ...been devised in metallic Na and electrolyte to enhance the cycle life. However, the improvements in 2D current collector in ester‐based electrolyte remain limited. Herein, a two‐alloys‐layer modified current collector (Na15Sn4/Cu6Sn5/Cu) has been constructed through electrodeposition and sodiation processes. The Na15Sn4/Cu6Sn5 alloys‐layer guarantees the dense plating of Na and establishes a credible connection between Na and substrate. The failure of sodium anode is attributed to the depletion of ester‐based electrolyte resulting from their side reactions, which could be mitigated on Na15Sn4 surface. Thus, the asymmetric cell, containing merely 100 µL electrolyte, achieves efficient Na plating/stripping for 110 times with an average Coulombic efficiency of 94.9%, which is superior than those reported using excessive fluorine‐rich electrolytes. The full cell consisting of an anode with 3 mAh cm−2 of Na on Na15Sn4/Cu6Sn5/Cu and a Na3V2(PO4)3 cathode demonstrates a capacity retention rate of 96% after 200 cycles at 1.0 C. By improving the Coulombic efficiency solely through the modified copper foil, this work provides a new route for the practical application of Na anode in ester‐based electrolytes.
A two‐alloys‐layer modified current collector (Na15Sn4/Cu6Sn5/Cu) has been constructed through electrodeposition and sodiation processes. The Na15Sn4/Cu6Sn5 alloys‐layer guarantees the dense plating of Na and establishes a credible connection between Na and substrate. The Na15Sn4 efficient suppresses the continuous consumption of ester‐based electrolyte, ensuring the long‐term efficient cycles of Na anode.
Abstract TiO 2 ‐based materials are considered to be the promising anodes of sodium‐ion batteries (NIBs) because of their high safety and good stability. However, their low specific capacity and high ...safety operating voltage plateau impose a severe challenge for high energy density batteries. Herein, interconnected micro‐sheets consisting of carbon nanotubes and sulfur doped TiO 2 (CNT/S‐TiO 2 ) are synthesized via an ultrasonic process and subsequent calcination, enabling the fabrication of high‐performance material. The utilization of SWCNT overcomes the structure instabilities during electrode preparation of thick electrodes. The incorporation of SWCNT and sulfur dopants in the CNT/S‐TiO 2 composite not only enhances conductivity but also improves ion transport dynamics, resulting in rapid charge delivery and high specific capacity at the thick electrode level. Consequently, CNT/S‐TiO 2 demonstrates excellent rate performance (from 0.3 to 15 C, with 72.4% capacity retention) and long cycling stability (10000 cycles at a load of 1.96 mg cm −2 ). More importantly, the high S‐TiO 2 content (90%) in the thick electrode (21.2 mg cm −2 ) achieves a high areal capacity retention of 3.4 mA h cm −2 after 100 cycles, which surpasses the actual application requirements.
To develop a carbon material derived from a green biomass source, this study investigated the production of a derivatized carbon material made from an industrial byproduct, litchi pericarp, through a ...hydrothermal reaction combined with a high-temperature heat treatment process, and its application in a new energy field was evaluated. Gratifyingly, in the field of sodium ion batteries, the material showed excellent electrochemical performance when evaluated as an anode: the material exhibited a high initial reversible capacity (336.4 mAh/g), an excellent retention rate (98.6%) after 120 cycles and good rate performance (183.2 mAh/g at 500 mA/g). The energy storage mechanism in the material was also determined. Moreover, for a fuel in direct carbon solid oxide fuel cells, the maximum power density was 239 mW/cm2 at 850 °C. When operating at a constant current density of 250 mA/cm2, the cell also displayed a stable discharging voltage and platform, and the fuel utilization rate was 66%. As a promising green carbon material with high electrochemical performance, the developed litchi pericarp-derived carbon material shows great potential in the new energy industry.
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•Litchi pericarp-derived carbon can be used in a wide range of clean energy fields.•The material can show excellent electrochemical performance in different systems.•The sodium storage mechanism was analyzed by different characterization methods.
Fiber-reinforced thermosetting resin composites are widely used in high-end manufacturing fields. The curing process involved resin flow, curing reaction, residual stress induced curing deformation ...and other steps. Numerical simulation of the forming process of fiber reinforced thermosetting resin composites was a complex problem of multi-field coupling. It was important theoretical and practical significance for the selection of process type, design of process parameters, and performance optimization of composite components to establish a perfect numerical simulation method to predict the curing behavior during the forming process. In this paper, the main research progress of numerical simulation of the forming process of fiber reinforced thermosetting resin composites is summarized. Moreover, the application conditions of different numerical models are discussed. The analysis of the application conditions of different models in the same field can guide the selection of the curing process and parameter desig
Buckling failure analysis of buried subsea pipeline under reverse fault displacement was investigated by the Vector Form Intrinsic Finite Element method in this paper, considering nonlinear ...soil–pipeline interaction in slit with sand and the multifold nonlinearities of nonlinear material, large deformation, large displacement and self-collision/contact. Two typical conditions discussed were the operation condition and the empty waiting state during installation, maintenance, and operation. Effects of soil properties, pressure loadings, diameter–thickness ratios and dip angles on local buckling formation, tensile strain and cross-sectional distortion were investigated. The results show that subsea pipelines obtain a large deformation capacity and the flexure curve shape is usually S-shape. The external pressure is more unfavorable than the internal pressure since it aggravates the compression strains but alleviates the tension strains. A small fault dip angle results in serious axial compression and can lead to local collapse in the empty waiting states. For big diameter–thickness ratios or great pressure level, external pressure will cause local collapse and even buckle propagation along the pipeline. Seven different modes of collapse and propagation are discovered in the empty waiting state. They can be classified by the first collapse location, buckle propagation direction and further propagation sustainability. The cross-sectional shapes after collapse and during propagation are mainly determined by the compression or tension state around the circum. These results can be used for the development of performance-based design methodologies for buried subsea pipelines.
•Buckling failure analysis of buried subsea pipeline based on VFIFE thin shell element.•Practical solution for multifold nonlinearities, especially the self-collision/contact problem.•Performance assessment of the operation condition and the empty waiting state.•Effect analysis of the fault dip angles, the diameter–thickness ratios and the pressure loadings.•Seven different modes of collapse and propagation discovered in the empty waiting state.
Abstract
To reach a closed‐loop material system and meet the urgent requirement of sustainable energy storage technologies, it is essential to incorporate efficient waste management into designing ...new energy storage materials. Here, a “two birds with one stone” strategy to transform rusty iron products into Prussian blue as high‐performance cathode materials, and recover the rusty iron products to their original status, is reported. Owing to the high crystalline and Na
+
content, the rusty iron derived Prussian blue shows a high specific capacity of 145 mAh g
−1
and excellent cycling stability over 3500 cycles. Through the in situ X‐ray diffraction and in situ Raman spectra, it is found that the impressive ion storage capability and stability are strongly related to the suppressed structure distortion during the charge/discharge process. The ion migration mechanism and the possibility to serve as a universal host for other kinds of ions are further illuminated by density functional theory calculations. This work provides a new strategy for recycling wasted materials into high value‐added materials for sustainable battery systems, and is adaptable in the nanomedicine, catalysis, sensors, and gas storage applications.
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