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In order to explore the effect of boundary layer thickness and pressure gradient on the performance of the flow field in the inlet, we design a high offset rate S-shaped inlet based on a certain unmanned aerial vehicle (UAV), and its author has analyzed the effect of boundary layer characteristics on the inlet with numerical simulation method. The suction of boundary layer which leads to separation zone not only becomes longer in the inlet, but also moves to the center plane of symmetry, the separation point of boundary layer appears in advance as pressure gradient increases. Considering the influence of the boundary layer, various performance parameters all exceeds that of the uniform entrance inlet conditions, especially the circumferential total pressure distortion of outlet increased by 58.2% at most, obviously can’t meet the engine to work properly, so we must consider and pay attention to the effect of the boundary layer characteristics on the flow field in the S-shaped inlet.

This paper based on the theory of space syntax took Luochengtou Village in Handan City, Hebei Province for example, tried to figure out a proper way for the renewal of urban villages, and change the current dilemma of "one-size-fits-all" and "removing all" in most cases, and put forward that local conditions and regional characteristics must be considered to propose the renewal strategies more suitable for the targeted objects. Based on the space syntax Depthmap software and field investigation, the paper analyzed the accessibility, intelligibility and throughput of public spaces in Luochengtou Village, and put forward 3 optimization strategies in view of the problems such as insufficient public spaces, poor accessibility and intelligibility of roads, and poor activity of spaces, specifically, increasing public activity spaces, sorting out public space network, and creating active space nodes, so as to optimize public environment of the village, enhance villagers' sense of belonging, sense of safety and sense of identity. [ABSTRACT FROM AUTHOR]

Single‐crystal nickel‐rich cathode materials (SC‐NRCMs) are the most promising candidates for next‐generation power batteries which enable longer driving range and reliable safety. In this review, the outstanding advantages of SC‐NRCMs are discussed systematically in aspects of structural and thermal stabilities. Particularly, the intergranular‐crack‐free morphology exhibits superior cycling performance and negligible parasitic reactions even under severe conditions. Besides, various synthetic methods are summarized and the relation between precursor, sintering process, and final single‐crystal products are revealed, providing a full view of synthetic methods. Then, challenges of SC‐NRCMs in fields of kinetics of lithium diffusion and the one particularly occurred at high voltage (intragranular cracks and aggravated parasitic reactions) are discussed. The corresponding mechanism and modifications are also referred. Through this review, it is aimed to highlight the magical morphology of SC‐NRCMs for application perspective and provide a reference for following researchers. [ABSTRACT FROM AUTHOR]

A magnetic toron is a spatially localized three-dimensional spin texture composed of skyrmionic layers with two Bloch points at its two ends. The magnetic toron can, thus, be stabilized in chiral magnets using external fields. In this work, we studied the toron dynamics induced by electric currents in a cylindrical nanowire using micromagnetic simulations. We show that the toron performs a unidirectional motion in a nanowire where the current is applied along the wire direction. The current-induced toron motion can be divided into three regions: static region for a small current due to the pinning effect, toron moving region for a large current, and toron annihilation region for a large reversal current. Moreover, the moving direction can be tuned by the sign of Dzyaloshinskii–Moriya interaction. Such peculiar dynamics indicates that the magnetic toron is a possible candidate as an information carrier. [ABSTRACT FROM AUTHOR]

Infinite volume expansion and high reactivity severely hinder the commercial applications of lithium metal batteries. Moreover, the short circuit caused by Li dendrites is fatal for the long-term performance of lithium metal batteries and may cause safety problems. Herein, lithiophilic silver/lithium (Ag/Li) composite anodes are synthesized via a spontaneous displacement reaction between silver nitrate and Li foil at room temperature, which can settle the above challenges by regulating Li nucleation and homogenizing Li-ion flux. Benefiting from the lithiophilic design, Li ion realizes zero nucleation overpotential on the as-obtained Ag/Li anodes with abundant spherical silver nanoparticles. Additionally, the by-product, lithium nitrate, acts as an electrolyte additive, which further ensures uniform Li deposition. Consequently, Ag/Li symmetric cells demonstrate ultralong lifespan with repeated plating/stripping for 1000 cycles at the current densities of 1 mA cm−2 and 5 mA cm−2, with negligible voltage fluctuations. Furthermore, the full-cell devices, paired with LiFePO4, also exhibit excellent electrochemical performance. The facile and effective strategy provides a promising prospect for commercial applications of lithium metal batteries. [ABSTRACT FROM AUTHOR]

Tin oxides as some of the potential candidates for commercial graphite anodes suffer from serious drawbacks such as poor electronic conductivity and large volume variation during cycling. Dispersing nanostructured SnOx into a carbon matrix may be an effective strategy to solve these problems. In this work, a novel dried plum-like yolk–shell SnOx/C architecture with high specific surface area and superior structural stability is constructed by an extremely facile and scalable spray pyrolysis method in ten seconds. The SnOx nanodots (＜10 nm) are uniformly embedded into the in situ generated carbon matrix. Polyvinylpyrrolidone is introduced here as a multifunctional agent to generate the dried plum-like yolk–shell morphology as well as to form the carbon matrix. The formation mechanism of such a unique morphology is discussed and revealed with in-depth comparison. As an anode for lithium ion batteries, the characteristic SnOx/C yolk–shell microspheres exhibit a high reversible capacity of 1142 mA h g−1 at 0.2 A g−1, good rate capability of 509 mA h g−1 at 5 A g−1, and excellent cycling performance of ∼100% capacity retention in 600 cycles. This work provides an ultra-simple route for large scale production of yolk–shell nanomaterials for energy-related as well as other applications. [ABSTRACT FROM AUTHOR]

To suppress the capacity fade of Li-rich Li1.2Ni0.13Co0.13Mn0.54O2 material as cathode materials for lithium-ion battery, we introduce a LiF coating layer on the surface to improve the cycling performance of Li1.2Ni0.13Co0.13Mn0.54O2 material. The modified sample shows a capacity of 163.2 mAh g−1 with a capacity retention of 95% after 100 cycles at a current density of 250 mA g−1, while the pristine sample only delivers a capacity of 129.9 mAh g−1 with a capacity retention of 82%. Compared with the pristine material, the LiF-modified sample exhibits an obvious enhancement in the electrochemical performance, which will be very beneficial for this material to be commercialized on the new energy vehicles and other related areas. [ABSTRACT FROM AUTHOR]

We present a novel system for sketch-based face image editing, enabling users to edit images intuitively by sketching a few strokes on a region of interest. Our interface features tools to express a desired image manipulation by providing both geometry and color constraints as user-drawn strokes. As an alternative to the direct user input, our proposed system naturally supports a copy-paste mode, which allows users to edit a given image region by using parts of another exemplar image without the need of hand-drawn sketching at all. The proposed interface runs in real-time and facilitates an interactive and iterative workflow to quickly express the intended edits. Our system is based on a novel sketch domain and a convolutional neural network trained end-to-end to automatically learn to render image regions corresponding to the input strokes. To achieve high quality and semantically consistent results we train our neural network on two simultaneous tasks, namely image completion and image translation. To the best of our knowledge, we are the first to combine these two tasks in a unified framework for interactive image editing. Our results show that the proposed sketch domain, network architecture, and training procedure generalize well to real user input and enable high quality synthesis results without additional post-processing. [ABSTRACT FROM AUTHOR]

In this work, Sn is used to dope the Li-rich cathode material to improve the electrochemical performance of Li ion battery. After Sn treatment, the lattice parameters a , c and lattice volume V become larger. Compared with the pristine sample, the Sn-contained samples show longer plateaux at about 4.5 V in the first charging process, which means that Sn can activate the Li 2 MnO 3 component. Meanwhile, with appropriate content of Sn doping, the sample exhibits enhanced rate capability and cycling stability. Especially, the sample S10 shows the best electrochemical performance, with a capacity retention of 88.66% after 100 cycles at 1 C (1 C=250 mA g −1 ). The mechanisms of Sn doping have also been investigated. The increased activation of Li 2 MnO 3 is due to the improved conductivity of Li 2 MnO 3 phase by Sn doping, and the enhanced electrochemical performance is mainly ascribed to the increased ability of Li ion diffusing into bulk phase and the improved structure stability during the prolonged charge-discharge cycles. It is suggested that Sn doping is an effective way to improve the electrochemical performance of Li-rich cathode material. [ABSTRACT FROM AUTHOR]

The composite of Co 3 O 4 , Co and graphitized carbon is synthesized by carbonization and cobalt-catalyzed-graphitization of carboxymethyl chitosan, followed by low-temperature thermal oxidation. At the high temperature, the Co(+2) is reduced to metallic Co and the produced Co acts as a catalyst for the graphitization of the pyrolytic carbon. The low-temperature oxidation is conducted to selectively oxidize Co to Co 3 O 4 while the carbon remains unreacted. The structure analysis indicates that three crystal phases (graphite, metallic Co, Co 3 O 4 ) accompanied with amorphous carbon are co-existed in the composite. Morphological results demonstrate that a lot of graphite grains around the Co element are distributed in the carbon. The electrochemical testing results indicate that the composite shows good electrochemical performance. It delivers a reversible capacity of 843 mAh g −1 at low current density, and remains 88.9% after 60 cycles at 200 mA g −1 . Even performed at 1 A g −1 , it also exhibits 493 mAh g −1 . The performance improvement is mainly due to the high capacity of Co 3 O 4 , high conductivity of graphitic carbon and metallic cobalt, the porous structure offering enough ion transport pathways and relieving the strain during cycling. [ABSTRACT FROM AUTHOR]

Target identification is one of the most critical steps following cell-based phenotypic chemical screens aimed at identifying compounds with potential uses in cell biology and for developing novel disease therapies. Current in silico target identification methods, including chemical similarity database searches, are limited to single or sequential ligand analysis that have limited capabilities for accurate deconvolution of a large number of compounds with diverse chemical structures. Here, we present CSNAP (Chemical Similarity Network Analysis Pulldown), a new computational target identification method that utilizes chemical similarity networks for large-scale chemotype (consensus chemical pattern) recognition and drug target profiling. Our benchmark study showed that CSNAP can achieve an overall higher accuracy (>80%) of target prediction with respect to representative chemotypes in large (>200) compound sets, in comparison to the SEA approach (60–70%). Additionally, CSNAP is capable of integrating with biological knowledge-based databases (Uniprot, GO) and high-throughput biology platforms (proteomic, genetic, etc) for system-wise drug target validation. To demonstrate the utility of the CSNAP approach, we combined CSNAP's target prediction with experimental ligand evaluation to identify the major mitotic targets of hit compounds from a cell-based chemical screen and we highlight novel compounds targeting microtubules, an important cancer therapeutic target. The CSNAP method is freely available and can be accessed from the CSNAP web server (). [ABSTRACT FROM AUTHOR]

Spinel LiMn2O4 was synthesized by a solid-state method. A 204468-size battery was fabricated and stored at 55°C. The structure and morphology of the LiMn2O4 cathode were analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM) technique. Energy dispersive spectroscopy (EDS) was used to analyze the surface component of the carbon anode. The discharge capacities of LiMn2O4 stored for 0, 24, 48, and 96 h are 106, 98, 96, and 92 mAh·g−1, respectively. The cyclic performance is improved after storage. The capacity retentions of LiMn2O4 stored for 0, 24, 48, and 96 h are 83.8%, 85.8%, 86.9%, and 88.6% after 180 cycles. The intensity of all the LiMn2O4 diffraction peaks is weakened. Mn is detected from the carbon electrode when the battery is stored for 96 h. Cyclic voltammograms and electrochemical impedance spectroscopy (EIS) were used to examine the surface state of the electrode after storage. The results show that the resistance and polarization of LiMn2O4/electrolyte is increased after storage, which is responsible for the fading of capacity. [ABSTRACT FROM AUTHOR]

The solid electrolyte interphase (SEI) plays an important role in the comprehensive electrochemical performance of lithium‐ion batteries. However, graphite generates a 10% volume expansion during cycles, resulting in structural cracking of the SEI and further electrolyte decomposition. Herein, by adjusting the formation current density, the composition and structure of the SEI are regulated to optimize the electrochemical performance of graphite electrodes. The results manifest that the SEI is mainly formed between 1.1 and 1.4 V, and a lower formation current density is favorable for forming an excellent SEI at the graphite electrode surface. The SEI formed under such condition possesses more organic lithium salts and less inorganic lithium salts, and it is enwrapped onto the surface of the graphite anode more uniformly as compared with higher formation current density. Meanwhile, the derived SEI is more stable and thicker, which can effectively stabilize the interface of the electrode/electrolyte to enhance the cyclic stability of graphite anode materials after the formation step, so as to buffer its volume change during the cycles. [ABSTRACT FROM AUTHOR]

In this study, a material-oriented metallurgical strategy, which is of such characteristics as short process, energy conservation and cost saving, is proposed to treat high-grade nickel matte and simultaneously produce LiNi 0.80 Co 0.15 Al 0.05 O 2 cathode material for lithium ion batteries. This process is mainly composed of four steps, which is oxidation roasting, two-stage leaching, purification and material synthesis. First, high-grade nickel matte is roasted to eliminate sulfur under air atmosphere. Then the roasted product is first leached to selectively remove 78.10% Cu with little Ni and Co extraction at atmospheric temperature under optimum conditions (25 °C, HCl 1.50 mol L−1, L/S 7.0, 30 min). After that, 96.23% Ni, 96.58% Cu and 84.18% Co are extracted in thermal leaching process under optimum conditions (70 °C, HCl 3.0 mol L−1, L/S 10.0, 120 min), leaving Fe, Zn and Ca in residue. The obtained lixivium is purified by solvent extraction method to adjust the mass ratio of Cu and Ni to the range that meets the requirement for preparation of cathode material. Finally, LiNi 0.80 Co 0.15 Al 0.05 O 2 material is produced by spray pyrolysis and sintering. The electrochemical performance of the resulting material is comparable with that prepared from analytical reagents, indicating such process can realize the comprehensive utilization of high-grade nickel matte. • Material-oriented metallurgy is firstly introduced to handle high-grade nickel matte. • High-grade nickel matte can be comprehensively utilized without deep separation. • LiNi 0.8 Co 0.15 Al 0.05 O 2 cathode material is produced from high-grade nickel matte successfully. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • High Li extraction without employing any roasting process. • An alum mixture (K, Rb, and Cs) was obtained with AlF(SO 4) 2 and Al 2 (SO 4) 3 during precipitation. • The K/Al ratio, pH and fluorine content significantly affected the separation efficiency of Al. • Detailed study of the transformation of AlF x (3−x)+ and F− by neutralization. • Al and F played significant roles in the recovery of alkali metals from lepidolite. Abstract The treatment of lepidolite by a multistage leaching process was studied for the extraction of alkali metals as alkali alums and brines. The precipitation characteristics of the aluminum and fluorine in the solution were also investigated. The transformation of the mineralogical species in lepidolite into albite and silicon dioxide was tentatively identified by X-ray diffraction measurements. The crystallization was aimed at the separation of rubidium and cesium from an acidic solution containing potassium as the main contaminant. The alum mixture contained on average 7.5% potassium, 1.3% rubidium and 0.30% cesium. The main crystalline components were aluminum sulfate and AlF(SO 4)·5H 2 O after concentration. The aluminum in the solution was removed by adding potassium sulfate with a K/Al mole ratio of 2 at various pHs to yield an overall aluminum precipitation of 62.1–66.6%. Under weakly acidic and neutral conditions, soluble aluminum may transform into insoluble aluminum, such as Al(OH) 3. Additionally, soluble AlF x (3−x)+ species tended to precipitate directly with OH−, thereby achieving the formation of Al-OH-F complexes. The AlF x (3−x)+ species at high pH were partially dissociated into F− and AlOH2+, Al(OH) 2 + and Al(OH) 4 −, and the buffering effect of F− inhibited the transformation of the precipitated Al(OH) 3 into soluble aluminates due to the formation of Al-OH-F complexes. The residual aluminum and fluorine contents were on average 0.0065 g/L and 0.042 g/L, respectively, in the mother liquor after neutralization at pH 9. The loss of lithium increased from 1.1% to 5.4% as the pH increased from 5 to 9. These findings imply that aluminum and fluorine can play significant roles in the recovery of alkali metals from lepidolite, and the precipitation of aluminum from leaching solutions as alums can cause a loss of lithium. [ABSTRACT FROM AUTHOR]

Abstract: The self-assembly of porous-graphite/silicon/carbon composites is fabricated by electrostatic attraction in solvent and pyrolysis method. Silicon carries a positive charge after surface modification and porous-graphite carries a negative charge after oxidation. Transmission electron microscopy reveals some Si nanoparticles encapsulated in pores of porous-graphite. X-ray diffraction shows that the structure of porous-graphite and silicon are not destroyed during oxidation of the graphite and surface modification of the silicon with APTES. Galvanostatic charge/discharge tests demonstrate that porous-graphite/silicon/carbon composites have much higher reversible charge capacity than flake graphite and better capacity retation than pristine silicon. The composites exhibit an initial reversible charge capacity of 778.8mAh·g−1. [Copyright &y& Elsevier]