Copper nanoparticles coated graphene nanoplates reinforced Al (Cu-GNPs/Al) matrix composites were fabricated by the combination of low temperature ball milling (LTBM) and subsequent hot extrusion ...process. The as-obtained composite with 2.5 wt% Cu-GNPs showed excellent comprehensive properties, i.e. the tensile strength (402 MPa) is 130% higher than that of monolithic Al, meanwhile, the fracture elongation over 10% was maintained. It was found that compared with room temperature ball milling, the LTBM processing could improve the dispersion of graphene in the matrix remarkably and thus enhance the strength of the composites substantially. The introduction of Cu-GNPs weakened the fiber texture of the Al matrix but refined grains as well as reduced the thermal expansion coefficient of the composites. The coated Cu on the GNPs enriched at the interface and inhibited the severe interfacial reaction, which would enable the structural integrity retention of GNPs and improved the interfacial bonding strength and thus be very favorable for the load transfer between GNPs and Al matrix. In addition, two sizes of GNPs were found in the composites due to the ball milling processing, the larger-sized GNPs contributed a lot to the load transfer while the smaller ones contributed more to the Orowan strengthening.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Non-alcoholic fatty liver disease (NAFLD) is increasingly prevalent and represents a growing challenge in terms of prevention and treatment. The purpose of this study is to investigate the protective ...effects of ginsenoside Rg1 (Rg1), an active ingredient of a natural medicine, and further clarify its protective mechanisms, in a mouse model of NAFLD induced by a high-fat diet. Rg1 significantly reduced liver weight, serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), triglyceride (TG), liver free fatty acids (FFAs) and malondialdehyde (MDA) levels, and increased superoxide dismutase (SOD) activity. Rg1 also upregulated the expression of peroxisome proliferator-activated receptor-alpha (PPARα), which stimulated fatty acid beta oxidation and promoted the metabolism of FFAs and TG. It also suppressed the expression of CCAAT/enhancer binding protein (C/EBP) homologous protein (CHOP), cysteine-containing aspartate-specific proteases 12 (Caspase 12), and glucose-regulated protein78 (GRP78), which reduced endoplasmic reticulum (ER) stress. Furthermore, Rg1 alleviated liver inflammation by inhibiting the activation of nucleotide binding oligomerization domain (NOD)-like receptor family pyrin domain-containing 3 (NLRP3) and thus reduced the production of inflammatory cytokines, such as interleukin 1-beta (IL-1β) and interleukin 18 (IL-18). These results suggested that Rg1 may protect against NAFLD, through regulation of lipid peroxidation, ER stress and inflammasome activation.
Gesture recognition in non-intrusive muscle-computer interfaces is usually based on windowed descriptive and discriminatory surface electromyography (sEMG) features because the recorded amplitude of ...a myoelectric signal may rapidly fluctuate between voltages above and below zero. Here, we present that the patterns inside the instantaneous values of high-density sEMG enables gesture recognition to be performed merely with sEMG signals at a specific instant. We introduce the concept of an sEMG image spatially composed from high-density sEMG and verify our findings from a computational perspective with experiments on gesture recognition based on sEMG images with a classification scheme of a deep convolutional network. Without any windowed features, the resultant recognition accuracy of an 8-gesture within-subject test reached 89.3% on a single frame of sEMG image and reached 99.0% using simple majority voting over 40 frames with a 1,000 Hz sampling rate. Experiments on the recognition of 52 gestures of NinaPro database and 27 gestures of CSL-HDEMG database also validated that our approach outperforms state-of-the-arts methods. Our findings are a starting point for the development of more fluid and natural muscle-computer interfaces with very little observational latency. For example, active prostheses and exoskeletons based on high-density electrodes could be controlled with instantaneous responses.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
A facile and scalable in situ synthesis strategy is developed to fabricate carbon-encapsulated Fe3O4 nanoparticles homogeneously embedded in two-dimensional (2D) porous graphitic carbon nanosheets ...(Fe3O4@C@PGC nanosheets) as a durable high-rate lithium ion battery anode material. With assistance of the surface of NaCl particles, 2D Fe@C@PGC nanosheets can be in situ synthesized by using the Fe(NO3)3·9H2O and C6H12O6 as the metal and carbon precursor, respectively. After annealing under air, the Fe@C@PGC nanosheets can be converted to Fe3O4@C@PGC nanosheets, in which Fe3O4 nanoparticles (∼18.2 nm) coated with conformal and thin onion-like carbon shells are homogeneously embedded in 2D high-conducting carbon nanosheets with a thickness of less than 30 nm. In the constructed architecture, the thin carbon shells can avoid the direct exposure of encapsulated Fe3O4 to the electrolyte and preserve the structural and interfacial stabilization of Fe3O4 nanoparticles. Meanwhile, the flexible and conductive PGC nanosheets can accommodate the mechanical stress induced by the volume change of embedded Fe3O4@C nanoparticles as well as inhibit the aggregation of Fe3O4 nanoparticles and thus maintain the structural and electrical integrity of the Fe3O4@C@PGC electrode during the lithiation/delithiation processes. As a result, this Fe3O4@C@PGC electrode exhibits superhigh rate capability (858, 587, and 311 mAh/g at 5, 10, and 20 C, respectively, 1 C = 1 A/g) and extremely excellent cycling performance at high rates (only 3.47% capacity loss after 350 cycles at a high rate of 10 C), which is the best one ever reported for an Fe3O4-based electrode including various nanostructured Fe3O4 anode materials, composite electrodes, etc.
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IJS, KILJ, NUK, PNG, UL, UM
As a typical representative of sulfonamides，sulfamethoxazole （SMZ） has a potential threat to biological phosphorus removal process. In order to explore its impact on biological phosphorus removal ...performance and its mechanism，a sequencing batch reactor was constructed to determine the impact of sulfamethoxazole on reactor performance，explore the impact of sulfamethoxazole on the content of microbial metabolic intermediates（poly-P，PHB and glycogen） and the activity of key enzymes（PPX，PPK）. Moreover， the micro mechanism of sulfamethoxazole on key enzymes were analyzed with molecular docking technology. The results showed that low concentrations of sulfamethoxazole（0.05 mg/L and 0.1 mg/L） had no significant effect on biological phosphorus removal performance，the content of metabolic intermediates and the activity of key enzymes. When the concentration of sulfamethoxazole increased to 1 mg/L，it began to inhibit biological phosphorus removal performance. With the increase of its concentration，the inhibition increa
Simultaneously achieving high strength and ductility is a critical issue for graphene reinforced aluminum matrix composites, which couldn't be resolved by the conventional mechanical milling-powder ...metallurgy technology due to the following reasons. On one hand, the low addition of graphene in the matrix traceable to its poor dispersibility limits the further strength improvement. On the other hand, the introduced graphene tends to distribute into grain boundaries rather than inside grains, which would result in stress concentrations at grain boundaries and localized strains, leading to the poor ductility of graphene/Al composites. In this work, intragranular nano-sized graphene nanoplates with high-content were dispersed in the matrix uniformly by a modified ball milling strategy, which induces that the strength and uniform elongation of the composites were simultaneously enhanced due to the improved work hardenability. Furthermore, the strengthening and toughening mechanisms were also discussed. This work offers a new insight into the fabrication and design of graphene/Al composites with both high strength and ductility.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
A general ultrathin‐nanosheet‐induced strategy for producing a 3D mesoporous network of Co3O4 is reported. The fabrication process introduces a 3D N‐doped carbon network to adsorb metal cobalt ions ...via dipping process. Then, this carbon matrix serves as the sacrificed template, whose N‐doping effect and ultrathin nanosheet features play critical roles for controlling the formation of Co3O4 networks. The obtained material exhibits a 3D interconnected architecture with large specific surface area and abundant mesopores, which is constructed by nanoparticles. Merited by the optimized structure in three length scales of nanoparticles–mesopores–networks, this Co3O4 nanostructure possesses superior performance as a LIB anode: high capacity (1033 mAh g−1 at 0.1 A g−1) and long‐life stability (700 cycles at 5 A g−1). Moreover, this strategy is verified to be effective for producing other transition metal oxides, including Fe2O3, ZnO, Mn3O4, NiCo2O4, and CoFe2O4.
A general ultrathin‐nanosheet‐induced strategy is introduced for producing 3D mesoporous network of transition metal oxides (TMOs). An N‐doped carbon network serves as the sacrificed template, which can be applied to many kinds of TMOs. The obtained material exhibits an interconnected mesopore architecture and possesses superior performance as a lithium ion anode.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
A facile and scalable 2D spatial confinement strategy is developed for in situ synthesizing highly crystalline MoS2 nanosheets with few layers (≤5 layers) anchored on 3D porous carbon nanosheet ...networks (3D FL-MoS2@PCNNs) as lithium-ion battery anode. During the synthesis, 3D self-assembly of cubic NaCl particles is adopted to not only serve as a template to direct the growth of 3D porous carbon nanosheet networks, but also create a 2D-confined space to achieve the construction of few-layer MoS2 nanosheets robustly lain on the surface of carbon nanosheet walls. In the resulting 3D architecture, the intimate contact between the surfaces of MoS2 and carbon nanosheets can effectively avoid the aggregation and restacking of MoS2 as well as remarkably enhance the structural integrity of the electrode, while the conductive matrix of 3D porous carbon nanosheet networks can ensure fast transport of both electrons and ions in the whole electrode. As a result, this unique 3D architecture manifests an outstanding long-life cycling capability at high rates, namely, a specific capacity as large as 709 mAh g–1 is delivered at 2 A g–1 and maintains ∼95.2% even after 520 deep charge/discharge cycles. Apart from promising lithium-ion battery anode, this 3D FL-MoS2@PCNN composite also has immense potential for applications in other areas such as supercapacitor, catalysis, and sensors.
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Aiming at the problems of low analysis accuracy, incomplete information extraction and low quality of traditional remote sensing data automatic analysis and extraction methods, a new remote sensing ...big data automatic analysis and intelligent information extraction method is proposed. Automatic analysis of remote sensing big data is realized through the expression, retrieval and understanding of remote sensing big data, and intelligent information extraction is carried out on the basis of automatic analysis of remote sensing big data. According to the procedures of remote sensing data mining, data preprocessing, feature acquisition, target recognition and evaluation, intelligent information extraction can be realized by utilizing the good learnability of convolutional neural network. In order to verify that the proposed method is superior to the traditional method, six different experimental areas are used as experimental objects, and a comparative experiment is designed. Experimental results: The proposed method automatically analyzes and extracts the remote sensing data, which is superior to the traditional method in terms of integrity, correctness and quality.
Lithium-rich layered cathode Li1.2Mn0.54Ni0.13Co0.13O2 is synthesized by a co-precipitation method followed by high-temperature treatment and surface coated with different amount of amorphous FePO4. ...The microstructure and electrochemical performance of the as-prepared cathode materials are investigated systematically. It is demonstrated that the Li1.2Mn0.54Ni0.13Co0.13O2 particles are uniformly coated with amorphous FePO4. With proper amount of amorphous FePO4 coating layer, significant improvements in discharge capacity, initial Coulombic efficiency, rate capability, cycle performance, and thermal stability are achieved at room temperature. Specifically, the 3 wt.% FePO4-coated cathode exhibits the highest discharge specific capacities (271.7 mAh g−1 at C/20), improved initial Coulombic efficiency (85.1%), and best cyclability (discharge capacity of 202.6 mAh g−1 at C/2 after 100 cycles), while the 1 wt.% FePO4-coated cathode displays the best rate capability (194.3 mAh g−1 at 1 C rate and 167.9 mAh g−1 at 2 C rate). The charge–discharge curves and electrochemical impedance spectra reveal that the improved electrochemical performances are due to the suppression of both the oxygen vacancy elimination at the end of the first charge and side reactions of the cathode with the electrolyte, as well as the decrease in charge transfer polarization by the FePO4 coating layer.
► Li1.2Mn0.54Ni0.13Co0.13O2 coated with a uniform layer of FePO4 was synthesized. ► Electrochemical performance was significantly improved by FePO4 coating. ► FePO4 coating layer suppresses the side reactions with the electrolyte. ► FePO4 coating enhances kinetics of Li1.2Mn0.54Ni0.13Co0.13O2 material.
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