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In this study, Ni/W–TiN composites were fabricated by the pulse current electrodeposition (PCE) method. The effects of TiN concentration on the microstructure, microhardness, and wear properties of the resulting composites were investigated by scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD), microhardness tester, and friction wear testing. Among the four obtained composites, Ni/W–TiN composite prepared at 8 g/L showed the densest and finest surface structure. The TiN contents in obtained Ni/W–TiN composites at 8 and 16 g/L were estimated to 8.1 and 5.4 wt%, respectively. The average Ni/W grain diameter in Ni/W–TiN composite obtained at 8 g/L TiN was recorded as 84.7 nm. The protrusion and depression heights of the composite deposited at 8 g/L were 81.8 and 45.4 nm, respectively. This composite also processed an average microhardness of 897.6 HV, with only a few shallow and narrow scratches on its worn surface, demonstrating its prominent wear resistance when compared to the other three composites.

Autonomous object detection powered by cutting-edge artificial intelligent techniques has been an essential component for sustaining complex smart city systems. Fine-grained image classification focuses on recognizing subcategories of specific levels of images. As a result of the high similarity between images in the same category and the high dissimilarity in the same subcategories, it has always been a challenging problem in computer vision. Traditional approaches usually rely on exploring only the visual information in images. Therefore, this paper proposes a novel Knowledge Graph Representation Fusion (KGRF) framework to introduce prior knowledge into fine-grained image classification task. Specifically, the Graph Attention Network (GAT) is employed to learn the knowledge representation from the constructed knowledge graph modeling the categories-subcategories and subcategories-attributes associations. By introducing the Multimodal Compact Bilinear (MCB) module, the framework can fully integrate the knowledge representation and visual features for learning the high-level image features. Extensive experiments on the Caltech-UCSD Birds-200-2011 dataset verify the superiority of our proposed framework over several existing state-of-the-art methods.

Hydraulic flushing drilling technology can not only improve the efficiency of high-pressure and low-permeability geological reservoir coalbed methane drainage but also effectively reduce the probability of coal and gas outburst disasters through pressure relief. The main mechanism of this technology is to expand the borehole diameter through hydraulic flushing measures, increase the strain of the coal around the borehole, and increase the development of cracked pores, to improve the permeability of the coal seam and realize the dual reduction of ground and gas pressure. However, in the actual application process, the interaction mechanism among the stress field, the structure field, and the seepage field is still not clear, and there is no clear method to accurately determine the pressure relief range based on the pressure relief mechanism in order to carry out reasonable drilling arrangements. Therefore, this article comprehensively uses laboratory experiments, numerical simulations, and field practices to fully explain the hydraulic flushing pressure relief mechanism and proposes a method to accurately determine the pressure relief range based on the radial line strain law. The results based on radial line strain showed that the effective relief radius expands to 0.86 m once adopting the Φ579 mm hydraulic flushing borehole compared to Φ160 mm; the borehole’s equivalent diameter of drilling field #11 is 2 to 3 times than that of #10 and 1.2 times the average CBM extraction amount. Therefore, as the borehole diameter increases, the permeability and radial line strain of the coal around the borehole increase significantly, but the tendency of the increase in permeability decreases with increasing vertical stress. The findings of this study can help for a better understanding of the pressure relief and permeability enhancement mechanism of hydraulic flushing, and the method of determining the pressure relief range based on radial strain can also provide a new way for other mines to practice ideas.

Sodium-ion batteries (SIBs), being an attractive candidate of lithium-ion batteries, have attracted widespread attention as a result of sufficient sodium resource with low price and their comparable suitability in the field of energy storage. However, one of the main challenges for their wide-scale application is to develop suitable anode materials with excellent electrochemical performance. Herein, a novel orderly layered VMoS2 (OL-VMS) anode material was synthesized through a facile hydrothermal self-assembly approach followed by a heating procedure. As the anode material of the SIBs, the unique structure of OL-VMS not only facilitated the rapid migration of sodium ions between the stacked layers but also provided a stable framework for the volume change in the process of intercalation/deintercalation. In addition, vanadium mediating in the framework caused more defects to produce abundant storage sites for Na+. As such, the obtained OL-VMS-based anode exhibited high reversible capacities of 602.9 mAh g-1 at 0.2 mA g-1 and 534 mAh g-1 even after 190-cycle operation at 2 A g-1. Furthermore, the OL-VMS-based anode delivered an outstanding specific capacity of 626.4 mAh g-1 after 100-cycle testing at 2 A g-1 in a voltage range from 0.01 to 3 V. In particular, even in the absence of conductive carbon, it still showed an excellent specific capacity of 260 mAh g-1 at 1 A g-1 after 130 cycles in a 0.3-3 V voltage range, which should contribute to the cost reduction and energy density increase.

Background: Immunotherapy has profoundly changed the landscape of cancer management and represented the most significant breakthrough. Yet, it is a formidable challenge that the majority of cancers - the so-called "cold" tumors - poorly respond to immunotherapy. To find a general immunoregulatory modality that can be applied to a broad spectrum of cancers is an urgent need. Methods: Magnetic hyperthermia (MHT) possesses promise in cancer therapy. We develop a safe and effective therapeutic strategy by using magnetism-mediated targeting MHT-immunotherapy in "cold" colon cancer. A magnetic liposomal system modified with cell-penetrating TAT peptide was developed for targeted delivery of a CSF1R inhibitor (BLZ945), which can block the CSF1-CSF1R pathway and reduce M2 macrophages. The targeted delivery strategy is characterized by its magnetic navigation and TAT-promoting intratumoral penetration. Results: The liposomes (termed TAT-BLZmlips) can induce ICD and cause excessive CRT exposure on the cell surface, which transmits an "eat-me" signal to DCs to elicit immunity. The combination of MHT and BLZ945 can repolarize M2 macrophages in the tumor microenvironment to relieve immunosuppression, normalize the tumor blood vessels, and promote T-lymphocyte infiltration. The antitumor effector CD8+ T cells were increased after treatment. Conclusion: This work demonstrated that TAT-BLZmlips with magnetic navigation and MHT can remodel tumor microenvironment and activate immune responses and memory, thus inhibiting tumor growth and recurrence.

In this study, Ni–SiC composite coatings with improved wear and corrosion resistance were obtained by ultrasonic electrodeposition (UED) method. The microstructure, microhardness, corrosion and abrasion resistance, and sectional composition distribution of the composite coatings were investigated by atomic force microscopy (AFM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), electrochemical workstation, Vickers microhardness testing, and wear testing. AFM and HRTEM results revealed compact surface structure of Ni–SiC composite coating prepared by UED. Mean diameter of Ni crystals was 68.4 nm, whereas that of SiC nanoparticles present within the composite was 26.7 nm. According to XPS data, contents of Si in UED deposited Ni–SiC composite coating were approximately 23.7 at.%, whereas that of Ni was about 46.8 at.%. Ni–SiC composite coating deposited via UED method exhibited largest microhardness (715.7 HV) compared to other coatings, whereas nickel coating had mean microhardness of 485.8 HV. Icorr and Ecorr values of Ni–SiC composite coatings deposited via UED were 1.13 × 10−3 mA/cm2 and −0.311 V, respectively, indicating optimal level of corrosion resistance. Besides, surface morphological analysis of the coating revealed it to be glossy with only minor surface scratches, exhibiting the best wear resistance.

Knowledge graph completion has become a well-studied problem and a non-trivial task with the broad application of the knowledge graphs. Previously, a lot of works have been proposed to solve the knowledge graph completion problem, for example, a series of Trans model, semantic matching models, convolutional neural networks based methods and so on. However, a series of Trans models and semantic matching models only focused on the shadow information of the knowledge graph, thus failed to capture the implicit fine-grained feature in the triple of knowledge graphs; convolutional neural networks based methods learned more expressive feature for knowledge graph completion, and it also ignored the directional relation characteristic and implicit fine-grained feature in the triple. In this paper, we propose a novel knowledge graph completion model named directional multi-dimensional attention convolution model that explores directional information and an inherent deep expressive characteristic of the triple. At last, we evaluate our directional multi-dimensional attention convolution model based on three standard evaluation criteria in two robust datasets, and the experiment shows that our model achieves state-of-the-art MeanRank.

Due to the temperature and concentration determine the kinetic undercooling of interface growth and nucleation undercooling inside the melt, they play an important role in the solidification microstructure of the alloy. In this paper, the effect of temperature gradient and cooling rate on the dynamic undercooling was studied and the mechanism of the concentration at the solid-liquid interface on the kinetic undercooling during the continuous cooling process was analyzed. A calculation method for the coupling of temperature and concentration during Inconel 718 alloy solidification was developed, which can solve the problem that the concentration and temperature are difficult to be calculated at the same time in the numerical calculation.

The electrochemical performance of the Ni0.8Co0.15Al0.05LiO2 (NCAL) cathode was investigated by comparing it with the traditional La0.4Sr0.6Co0.2Fe0.8O3-δ (LSCF) and LSCF/Ce0.9Gd0.1O2-δ (GDC) cathodes with a GDC electrolyte-supported solid oxide fuel cell (SOFC). It is found that the electrochemical performance of the cells with the NCAL and NCAL/GDC cathode is better than that of the cells with the LSCF and LSCF/GDC cathode at 550 °C. The results of the electrochemical performance tests of the cells with different NCAL/GDC mass ratios (10/0, 9/1, 8/2, 7/3 and 6/4) show that the NCAL/GDC composite cathode with the mass ratio of 8/2 has the best electrochemical performance. XRD results show that when the sintering temperature is higher than 700 °C, the NCAL/GDC composite will undergo chemical reactions and generate new phases, reducing the performance of the composite cathode. XPS results show that a small amount of Li2CO3 was formed on the surface of NCAL during cathode preparation, forming a special interface between NCAL, Li2CO3 and GDC. At the NCAL-Li2CO3/GDC interfaces, due to the migration and aggregation of Li+ to the interface, a space charge region may be formed in which the Li+ enrichment may lead to the formation of the region with a high oxygen vacancy concentration. A very high oxygen vacancy concentration at the NCAL-Li2CO3/GDC interfaces will provide sufficient oxygen ion conductivity for oxygen reduction reaction (ORR) and reduce the activation energy of the reaction. NCAL will be a potential cathode material that can reduce the operating temperature of the traditional SOFC to 550 °C or lower.

To deal with the single-phase open-circuited fault, an enhanced fault-tolerant model predictive current control with continued modulation is proposed in this article. This method includes reconstructing the postfault vector distribution and adopting a multistep vector selection method. In the reconstruction procedure, the transition vectors are generating to realize standard pulsewidth modulation waveforms. Then, the unreachable area can be filled by creating new synthetic vectors. Finally, the vectors with oversized amplitudes are optimized by using null vectors. In order to cover the full modulation area, a multistep vector selection method is used to determine the phase angle and amplitude of the optimal vector. The phase angle can be determined by defining two cost functions and adopting duty cycle modulation technology. The amplitude of the optimal vector can be optimized by utilizing the duty cycle modulation technology again. The oscillation, due to the back electromotive force, is compensated in each step. A thorough experimental evaluation has been conducted to confirm the effectiveness and superiority of the proposed fault-tolerant method.

The effects of Li2CO3 and LiOH on the ionic conductivity of BaCe0.9Y0.1O3(BCY)-x%Li2CO3 (x = 0, 5, 10 and 30) and BCY-y%LiOH (y = 0, 2, 5 and 8) composite electrolytes were investigated. Symmetrical cells with the structure of foam Ni–Ni0.8Co0.15Al0.05LiO2 (NCAL)∖BCY-x%Li2CO3 or y%LiOH∖foam Ni-NCAL and Pt∖BCY-x%Li2CO3 or y%LiOH∖Pt were prepared with NCAL-coated foam Ni and porous Pt as symmetrical electrodes, respectively. The ionic conductivity test results of the cells with Pt as the symmetrical electrode showed that the addition of LiOH did not improve the ionic conductivity of the BCY electrolyte, while the addition of Li2CO3 could significantly improve the ionic conductivity of the BCY electrolyte. The maximum power density of the cells with the structure of foam Ni-NCAL∖BCY-x%Li2CO3 or y%LiOH∖foam Ni-NCAL decreases with the increase in the amount of Li2CO3 or LiOH, which indicates that adding Li2CO3 or LiOH to BCY via mechanical mixing did not improve the electrochemical performance of the cells with NCAL as the electrode, and the NCAL electrode has the greatest impact on the performance of the cells. The interface of Li2CO3 and BCY should be a high-speed channel for ion conduction. Increasing the effective area of the interface between BCY and Li2CO3 and optimizing its continuity in the electrolyte should be the main development direction for improving the ionic conductivity.

The hydrogen induced intergranular crack is most common in hydrogen embrittlement phenomenon. Hydrogen atoms will preferentially diffuse into grain boundaries and then accumulate in them. Therefore, it is necessary to reveal the diffusion mechanism of hydrogen atoms at grain boundaries, which is helpful for deeply understanding hydrogen embrittlement. In this work, we performed first-principles calculations to investigate the trapping sites and diffusion behaviours of hydrogen atoms at Σ3 [ 1 ¯ 10] (111), Σ5 [ 1 ¯ 00] (021) and Σ9 [110] (2 2 ¯ 1) grain boundary structures of γ-Fe. Hydrogen atoms have no tendency to be segregated from the bulk to the Σ3 GB but hydrogen atoms tend to segregate into the Σ5 and Σ9 GBs. The solution energy of hydrogen in grain boundaries is mainly the consequence of the chemical bonding between Fe atoms in GBs and the hydrogen atom. In addition, according to the hydrogen diffusion behaviour in grain boundaries, Σ3 and Σ5 GBs act as three-dimensional barriers for hydrogen migration while the Σ9 GB acts as a one-dimensional barrier for H diffusion. Significantly, the difficulty of hydrogen diffusion along grain boundary mainly depends on the connectivity of low electron density region along grain boundary. This conclusion can provide a deep understanding of hydrogen distributions at different grain boundaries in metal materials, which is helpful for hydrogen embrittlement resistant materials design on the basis of grain boundary regulation.

Ni-SiC composite coatings with good wear and corrosion resistance could be obtained by the ultrasonic electrodeposition (UED) method in this study. The microstructure, microhardness, corrosion and abrasion resistance, and sectional composition distribution of the composite coatings were investigated employing atomic force microscopy (AFM), scanning electron microscopy (SEM), x-ray photoelectron spectroscopy (XPS), electrochemical workstation, Vickers microhardness testing, and wear testing. In addition, the statistical distributions of Ni grains in Ni coating and Ni-SiC composites were counted by using a “Nano Measurer” software. The outcome of AFM and HRTEM revealed a compact surface structure of Ni-SiC composite coating made by the UED. The mean diameter of Ni crystals was 68.4 nm, whereas that of SiC nanoparticles present within the composite was 26.7 nm. According to the XPS data, the content of Si in the Ni-SiC composite coating prepared via UED was approximately 23.7 at.% whereas that of Ni was about 46.8 at.%. The Ni-SiC composite coating deposited via UED method was found to have the largest value for microhardness (715.7 HV) compared to other coatings, although the nickel coating had a mean microhardness of 485.8 HV only. The Icorr and Ecorr values of the Ni-SiC composite coating deposited via UED were 1.13 × 10−3 mA/cm2 and − 0.311 V, respectively, indicating an optimal level corrosion resistance. Besides, the surface morphological analysis of the coating revealed that it was glossy with only minor surface scratches, and it exhibited the best resistance to wear.

Density functional theory (DFT) calculations are used to explore the adsorption characteristics and degradation mechanism of sulfacetamide on anatase TiO2(101) and (001) surfaces. The most probable adsorption configuration was firstly determined by comparing the adsorption energies and structural bond lengths before and after adsorption. After adsorption, some of the bond lengths are elongated. We have proposed about six possible degradation pathways of sulfacetamide, such as branch chain breaking, benzene ring dihydroxylation, amino substitution and sulphur nitrogen bond breaking. And the relevant degradation processes are studied in detail. Based on the calculated results, we conclude that the TiO2(001) surface is more suitable for the degradation of sulfacetamide considering its much smaller energy barriers in several degradation paths than the TiO2(101). Among all the six possible degradation paths, we find that the hydroxyl radical attacks of C(1), C(3) and N(6) atoms of the (001) surface and the C(4) atom of (101) surface sulfacetamide are most probable reaction pathways due to their much smaller energy barriers, i.e. 7.7, 26.1 kcal mol−1 and 14.6, 23.4 kcal mol−1 indicating that these reactions can easily take place in room temperature. Our computational results are not only consistent with the experimental results of sulfacetamide degradation, but also reveal the possible microscopic mechanisms of the photocatalytic reaction.

Designing antibody-powered DNA nanodevice switches is crucial and fascinating to perform a variety of functions in response to specific antibodies as regulatory inputs, achieving highly sensitive detection by integration with simple amplified methods. In this work, we report a unique DNA-based conformational switch, powered by a targeted anti-digoxin mouse monoclonal antibody (anti-Dig) as a model, to rationally initiate the hybridization chain reaction (HCR) for enzyme-free signal amplification. As a proof-of-concept, both a fluorophore Cy3-labeled reporter hairpin (RH) in the 3' terminus and a single-stranded helper DNA (HS) were individually hybridized with a recognition single-stranded DNA (RS) modified with Dig hapten, while the unpaired loop of RH was hybridized with the exposed 3'-toehold of HS, isothermally self-assembling an intermediate metastable DNA structure. The introduction of target anti-Dig drove the concurrent conjugation with two tethered Dig haptens, powering the directional switch of this DNA structure into a stable conformation. In this case, the unlocked 3'-stem of RH was implemented to unfold the 5'-stem of the BHQ-2-labeled quench hairpin (QH), rationally initiating the HCR between them by the overlapping complementary hybridization. As a result, numerous pairs of Cy3 and BHQ-2 in the formed long double helix were located in spatial proximity. In response to this, the significant quenching of the fluorescence intensity of Cy3 by BHQ-2 was dependent on the variable concentration of anti-Dig, achieving a highly sensitive quantification down to the picomolar level based on a simplified protocol integrated with enzyme-free amplification.

This paper presents rigorous analytical solutions for cavity contraction analysis of a thick-walled cylinder/sphere after an arbitrary magnitude of expansion. Closed-form solutions are given for th...

We investigate multiwavelength-pumped optical frequency combs (OFCs) based on a new kind of coupling systems - a biconical microfiber coupler (MFC) combined with a fiber laser. Compared with other comb generations, this device possesses the advantages of an easy implementation and of achieving tunable pump wavelengths, which would increase the flexibility of the OFC generation. In essence, the adjustable cascaded four-wave mixing (FWM) process at the beginning stage of the frequency comb generation arouses different forms of OFCs. The proposed MFC coupling system holds promising applications in optical filtering, sensing, mode-switching and frequency combs.

The combination of microstructures and nanostructures has broad application prospects. However, most existing methods are oriented to fabricating microstructures and nanostructures separately, and the fabrication of nanostructures on a microstructured surface at the wafer level is rarely studied. In this work, a new method of fabricating large-area high aspect ratio nano-cylinders on micro-pillars based on a colloidal crystal mask is proposed. An experimental device for stripping and draining was designed to create a polystyrene colloidal crystal mask. Together with reactive-ion etching and metal-assisted chemical etching, high aspect ratio nano-cylinders on micro-pillars with controllable size were obtained on a 4-inch silicon wafer. Wetting tests were performed on four groups of fabricated structures of different sizes, and the results showed that all samples were superhydrophobic. Thus, a method for fabricating uniform, size-controllable, large-area high aspect ratio nano-cylinders on micro-pillars with great potential as a superhydrophobic engineering material is proposed.

The finite control set (FCS) model predictive current control (MPCC) is a promising control scheme for the five-phase drives due to the easy-tuning process. However, the deteriorated operational performance and huge computational burden are the real challenges. This article proposes a multivector FCS-MPCC, which can improve the operational performances without increasing computational burden. In the proposed method, the candidate virtual voltage vectors with harmonics-free are employed as the basic control set. Then, each sector is partitioned to generate more available vectors. The duty-cycle modulation technology is used to optimize the amplitude of the candidate vector. Therefore, a better control effect can be obtained. Also, a sector judgment method is proposed to determine the optimal control set, which can reduce the computational burden. By using this method, the optimal vector can be selected accurately without evaluating all the available vectors. Thus, the computational burden can be alleviated. The experimental results are presented to confirm the effectiveness of the proposed multivector FCS-MPCC method.

Plant-derived polyphenol coating offers a promising route to fabricate functional surfaces for different substrate materials. However, almost all of the deposition approaches are time-consuming and involve inefficient processes, and the mechanisms behind the coating deposition are rarely understood. Herein, we report a rational methodology to achieve the rapid deposition of poly(caffeic acid) (PCA) by using H2O2 as a trigger under the assistance of copper sulfate (CuSO4). The comparative monomer structure of PCA oxidation polymerization has illustrated a significant distinction in the reaction path for PCA coating deposition which has never been reported before. Until now, the unprecedented fast velocity for polyphenol coating has been obtained, and the PCA coating exhibits excellent homogeneity, spatiotemporal tunability, and firm stability. Moreover, three different types of filtration membranes, poly(vinylidene fluoride) microfiltration membrane (PVDF MF membrane), poly(ether sulfone) (PES) ultrafiltration (UF) hollow fiber membrane, and PCA-coated PES nanofiltration (NF) membrane, are all successfully dip-coated using H2O2-triggered PCA coating. Without synthetic complexities and intricate procedures, the formation of hydrophilic and homogeneous PCA aggregates on the surface and/or inside pore walls resulted in various membranes. The as-prepared PCA-coated PVDF MF membrane demonstrates excellent oil/water separation efficiency of less than 150 ppm and a flux recovery rate of approximately 90% even after five cycles. By one-step co-deposition of PCA and poly(2-ethyl-2-oxazoline) (PEtOx) on the PES UF membrane surface, hydrophilicity and biofouling resistance are implemented for efficient protein filtration. The PES NF membrane formed by the PCA layer exhibits high mono-/divalent ion selectivity and excellent chlorine resistance. Overall, these results represent a rapid and sustainable approach to tailor PCA coatings for versatile liquid separation processes.

Silk fibroin (SF) and polyhydroxyalkanoate (PHA) have received increasing attention in recent years because of their unique biodegradability and biocompatibility. Studies on SF or PHA-based materials that are intended for use as biomaterials have attracted great attention, but few studies have been conducted on SF/PHA composite materials. Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) copolymers with varying ratios of the 3-hydroxyvalerate (HV) component are the most widely used member of PHAs. In this study, SF/PHBV composite nanofibers were prepared by electrospinning. The stability of the mixed solution of SF/PHBV was explored first. Fourier transform infrared (FTIR) spectroscopy was used to study the composition of the precipitates caused by mixing the SF solution with the PHBV solution. The morphology of the electrospun SF/PHBV composite nanofibers was observed by scanning electron microscopy (SEM). The average diameters of the pure PHBV, pure SF, SF/PHBV (the content ratio of solute SF/PHBV (w/w) was 10/1), and SF/PHBV (the content ratio of solute SF/PHBV (w/w) was 4/1) nanofibers were 495.12 ± 82.27, 67.88 ± 14.52, 171.10 ± 40.38, and 149.70 ± 28.57 nm, respectively. To discuss the influence of the electrospinning parameters on the spinning stability and morphology of the electrospun SF/PHBV (10/1) composite nanofibers, a univariate analysis experiment was designed. When the applied voltage was 15 kV, the feeding rate was 0.3 mL/h, and the tip-to-collector distance was 13 cm, the spinning stability, uniformity and formability of the SF/PHBV (10/1) composite nanofibers were excellent. In addition to FTIR analysis, X-ray diffraction (XRD) was also used to explore the structure of the electrospun SF/PHBV composite nanofibers. As the content of PHBV increased, the crystallinity of the SF/PHBV composite nanofibers could be improved. The thermogravimetric analysis (TGA) results indicated that the thermal stability of SF was better than that of PHBV. As the content of PHBV increased, the thermal stability of the SF/PHBV composite nanofibers would decrease.

Yttria-modified silicide (MoSi2-Y2O3) oxidation-resistant coatings with multiple Y2O3 contents were prepared using supersonic atmospheric plasma spraying, and the oxidation resistance was investigated at 1700 °C with static atmosphere. Experimental results indicated that the sprayed MoSi2-Y2O3 coating possessed good compactness, which adhered well to the SiC transition layer. Meanwhile, the Y2O3 addition greatly enhanced the bonding strength of the coating, and extended its service life at 1700 °C. Wherein the MoSi2-20 wt.%Y2O3 coating exhibited the highest adhesive strength and best oxidation resistance with the lowest mass loss among all the coatings. In practice, the Y2O3 changed the microstructures of formed oxide glass scale during oxidation, and then modified the oxidation resistance of the coating. The action mechanism of Y2O3 on the oxidation behavior of MoSi2-Y2O3 coating was analyzed.

The cycling performance of batteries is largely determined by the electrode-electrolyte interphase associated with the chemical and electrochemical properties of electrolyte salts and solvents. In ...

This study proposed a novel electroconductive carbon fiber/circulating fluidized bed fly ash based-geopolymer (CF/CFBFAG) composite, which possessed adjustable electrical conductivity and showed a ...

A solid oxide fuel cell with 1.2 mm thick nanocrystalline BCY (BaCe0.9Y0.1O3) electrolyte was prepared by the copressing method, and its electrochemical performance was tested in H2/air conditions. The maximum power density of the nanocrystalline electrolyte cell prepared with BCY powders calcined at 1000 °C and operated at 550 °C in H2 is 405.2 mW cm−2. The carriers of nanocrystalline BCY electrolyte were studied by using double-layer electrolyte cells with pure oxygen ion conductor GDC (Gd0.1Ce0.9O2) and proton conductor SCY (SrCe0.95Y0.05O3), sintered at high temperatures as proton and oxygen ion filters. It is found that nanocrystalline BCY is a mixed conductor of oxygen ions and protons. The results of hydrogen and oxygen concentration cells show that the transference number of oxygen ions in the nanocrystalline BCY prepared in this study is higher than that of protons. XPS and HRTEM results of BCY particles before and after performance testing showed that an amorphous layer containing a high concentration of oxygen vacancies and suspected carbonate was formed on the surface of BCY particles after fuel cell performance testing. We believe that the amorphous layer should be a high-speed ion conduction channel for nanocrystalline BCY electrolyte during performance testing.

To develop a new way of renewable utilization of ground granular blast furnace slag (GGBFS), a novel ZnO-loaded graphene-reinforced alkali-activated slag-based geopolymer (ZnO/GASG) nanocomposite was originally prepared. The photocatalytic performance of ZnO/GASG was evaluated by solar hydrogen production and wastewater treatment of dyeing pollutant. The mechanical strength results indicated that the lamellate graphene inserted in the substrate of alkali-activated slag-based geopolymer (ASG) has played a critical role in crack-arresting extension so as to lead the significant increases of compressive and flexural strengthens of GASG test block. The XRD, FESEM and XPS results revealed that ZnO in the form of amorphous state dispersed on the surface of GASG when the loading approached to 2 wt%, and ZnO existed in the form of zincite when the loading was greater than 10 wt%. UV–vis diffuse reflectance spectra demonstrated that the absorption edge all of ZnO/GASG nanocomposites were blue-shifted due to the quantum size effect. The highest photocatalytic activities for H2 production (2281.3 μmol/g) and wastewater degradation (95.7%, solar light) over 15ZnO/GASG composite were ascribed to the efficient separation of photoinduced electron-hole pairs. The hole and hydroxyl radical play significant role in photocatalytic degradation of dyeing pollutant.

Solid wastes exhibit excellent prospects in the removal of heavy metals from contaminated water. However, raw solid waste materials usually show mediocre uptake efficiency, it is imperative to func...

This study aims at addressing a problem on icing detection for Unmanned Aerial Vehicle (UAV for short) because traditional icing detection methods are costly and bulky. Toward this end, a pitot-based icing detection method is proposed, and the effect of different types of icing blocking on pressure is firstly reported. An icing detection system based on the pitot tube is designed and fabricated. Icing wind tunnel results indicate that if the pitot tube is blocked by glaze ice, then the total pressure of the pitot tube decreases gradually and remains unchanged and less than static pressure. However, if the pitot tube is blocked by rime ice, then the total pressure drops to the same level as the static pressure. If the pitot tube is blocked by non-ice organic materials, then the total pressure suddenly drops to the same level as the static pressure and remains unchanged. Furthermore, if the pitot tube contacts the water droplets but does not freeze, the total pressure output value fluctuates slightly. The effect of icing on pressure is caused by differences in ice microstructure, temperature, and flow velocity. At the same time, the proposed method offers a facile and low-cost approach for UAV icing detection.

Continuous cooling transformation (CCT) diagrams of undeformed and 40% compressively deformed pearlite heat-resistant steels at 950°C were obtained by a combined method of dilatometry and metallogr...

Using lithium compounds as anode in ceramic fuel cells will form LiOH/Li2CO3 at the anode, which diffuse into the Gd-doped CeO2 (GDC) electrolyte significantly improving its ionic conductivity. Here the importance of the density and microstructure of the electrolyte on this conductivity improvement is analyzed. Test cells with Ni0.8Co0.15Al0.05LiO2 (NCAL) electrode and GDC electrolyte are prepared at four sintering temperatures of 900, 1100, 1300, and 1550 °C. The amount of LiOH/Li2CO3 that enters into the electrolyte from the NCAL anode decreases with increasing sintering temperature, which led to lower electrolyte ionic conductivity and fuel cell performance. The results of XPS and EPR show that the concentration of oxygen vacancy in GDC containing LiOH/Li2CO3 increased significantly. The effective interface of LiOH/Li2CO3-GDC composite electrolyte results in higher ionic conductivity as compared to the composite electrolytes with larger grains and a smaller amount of LiOH/Li2CO3 due to higher sintering temperatures.

Modern advanced photonic integrated circuits require dense integration of high-speed electro-optic functional elements on a compact chip that consumes only moderate power. Energy efficiency, operation speed, and device dimension are thus crucial metrics underlying almost all current developments of photonic signal processing units. Recently, thin-film lithium niobate (LN) emerges as a promising platform for photonic integrated circuits. Here, we make an important step towards miniaturizing functional components on this platform, reporting high-speed LN electro-optic modulators, based upon photonic crystal nanobeam resonators. The devices exhibit a significant tuning efficiency up to 1.98 GHz V−1, a broad modulation bandwidth of 17.5 GHz, while with a tiny electro-optic modal volume of only 0.58 μm3. The modulators enable efficient electro-optic driving of high-Q photonic cavity modes in both adiabatic and non-adiabatic regimes, and allow us to achieve electro-optic switching at 11 Gb s−1 with a bit-switching energy as low as 22 fJ. The demonstration of energy efficient and high-speed electro-optic modulation at the wavelength scale paves a crucial foundation for realizing large-scale LN photonic integrated circuits that are of immense importance for broad applications in data communication, microwave photonics, and quantum photonics., Lithium niobate (LN) devices are promising for future photonic integrated circuits. Here, the authors demonstrate an electro-optic LN modulator with a very small modal volume based on photonic crystal resonator architecture.

Physicochemical properties of arsenic sulfide sludge (ASS) from copper smelter (ASS-I) and lead−zinc smelter (ASS-II) were examined by XRD, Raman spectroscopy, SEM−EDS, TG−DTA, XPS and chemical phase analysis method. The toxicity characteristic leaching procedure (TCLP), Chinese standard leaching tests (CSLT), three-stage sequential extraction procedure (BCR) and batch leaching experiments (BLE) were used to investigate the environmental stability. The ASSs from different smelters had obviously different physicochemical and environmental properties. The phase composition and micrograph analysis indicate that ASS-I mainly consists of super refined flocculent particles including amorphous arsenic sulfide adhered with amorphous sulfur and that ASS-II mainly consists of amorphous arsenic sulfide. The valence state of arsenic in both sludges is trivalent, but the valence composition of sulfur is quite different. The ASSs have thermal instability properties. The results of TCLP and CSLT indicate that the concentrations of As and Pd in the leaching solution exceed the standard limits. More than 5% and 90% of arsenic are in the form of acid soluble and oxidizable fractions, respectively, which explains the high arsenic leaching toxicity and environmental activity of ASS. This research provides comprehensive information for the disposal of ASS from copper and lead−zinc smelter.

For the purpose of exploring a potential process to produce FeMn, the effects of microwave heating on the carbothermal reduction characteristics of oxidized Mn ore was investigated. The microwave heating curve of the mixture of oxidized Mn ore and coke was analyzed in association with the characterization of dielectric properties. The comparative experiments were conducted on the carbothermal reductions through conventional and microwave heatings at temperatures ranging from 973 to 1373 K. The thermogravimetric analysis showed that carbothermal reactions under microwave heating proceeded to a greater extent and at a faster pace compared with those under conventional heating. The metal phases were observed in the microstructures only under microwave heating. The carbothermal reduction process under microwave heating was discussed. The electric and magnetic susceptibility differences were introduced into the thermodynamics analysis for the formation of metal Mn. The developed thermodynamics considered that microwave heating could make the reduction of MnO to Mn more accessible and increase the reduction extent.

Based on the density functional theory (DFT), the distribution of Al and Bronsted acid sites in zeolite ECR-1 were studied by utilization of SIESTA (Spanish Initiative for Electronic Simulations wi...

A series of compression tests were conducted at various temperatures and strain rates to experimentally investigate the hot-deformation characteristics and dynamic softening of an as-cast FeCrAl alloy. There is no evident decline in stress after the peak point of a flow curve despite the occurrence of dynamic recrystallization (DRX). This phenomenon pointed out that the occurrence of DRX in the alloy could not be identified depending only on flow curves. The constitutive equation for peak stress was constructed following the determination of hot-working parameters. The predicted results correlated well with the experimental data. The dynamic softening behavior was classified depending on the analysis of microstructure evolutions at different temperatures. The softening process was dominated by dynamic recovery (DRV) at 850 and 950 °C. The higher temperature could elevate the level of dynamic softening. The softening mechanisms at 1050 °C included DRV and continuous dynamic recrystallization (CDRX) characterized by the rotation of sub-grains from low-angle boundaries to high-angle boundaries. The rotation of sub-grains during the CDRX process was unlikely to affect the strong intensity of texture after the hot-deformation process.

Coal seam water injection is a widely used dust reduction technology in Chinese coal mines. During the process of coal seam water injection, a large amount of broken coal particles will accumulate in the pore, which will affect the flow characteristics of water. It's very important for improving the on-site coal seam water injection and dust reduction technology to study the influence of coal particles on the water migration law. In this paper, a spontaneous upward imbibition experiment was used to study the effect of coal particles stacked in front fractures on water migration in coal seam water infusion. Then, a mathematical model was established to express imbibition speed and stable imbibition height. The results show when the largest particle size is selected, theoretical calculation results of stable imbibition height is closest to the experimental data; coal particles with a size of 564–1589 μm have the greatest influence on the wetting phase of coal seam water infusion; the metamorphic grade and particle size of the samples mainly affect the initial stage of water migration, and the initial imbibition speed of each coal sample is quite different. However, with increasing imbibition height, the imbibition speed difference of each coal sample gradually decreases.

Twinning is commonly activated in plastic deformation of low stacking-fault face-centered cubic (Fcc) metals but rarely found in body-centered cubic (Bcc) metals under room temperature and slow strain rates. Here, by conducting in situ transmission electron microscopy (TEM) at atomic scale, we discover that, in stark contrast to those in most Fcc metals, a majority of deformation twins in Bcc metals are unstable and undergo spontaneously detwinning upon unloading. Such unexpected instability of Bcc twins is found to be closely related to the prevalence of the inclined twin boundaries—a peculiar structure where twin boundaries are not parallel to the twinning plane, and the degree of instability is in direct proportion to the fraction of the inclined twin boundary. This work provides significant insights into the structure and stability of deformation twins in Bcc metals., Body-centred cubic metals rarely show twinning during deformation. Here, the authors use high resolution transmission electron microscopy to show tungsten, a body-centred cubic metal, spontaneously undergoes detwinning when unloaded.

Rare earths with unique electronic structure and properties have incomparable advantages for modifying the comprehensive performance of silicide materials. In this study, MoSi2-based composite coatings with different rare-earth Yb2O3 contents were prepared using supersonic atmospheric plasma spraying, and their microstructural features and oxidation behavior at 1700 °C were investigated systematically. Results showed that the sprayed MoSi2-Yb2O3 composite coating possessed the dense structure without visible defects and tightly adhered to the SiC transition layer. During oxidation at 1700 °C, all the samples exhibited an explicit linear oxidation mode, in which the MoSi2-10 wt%Yb2O3 coating qualified the optimal oxidation resistance with the lowest specific mass loss relative to other coatings. It was natural to consider that the Yb2O3 dopant changed the microstructural aspects of the formed oxide scale upon oxidation, and then affecting the oxidation behavior of the applied coating. Moderate doping of Yb2O3 stabilized the Si–O covalent bonds in SiO2 network, leading to the enhanced viscosity of oxide glass scale, thereby delaying the effective delivery of oxygen molecules as well as the oxidation degradation of the coating.

The phase transformation and microstructure evolution of pearlite heat-resistant steel during heating were observed with an ultra-high temperature confocal scanning laser microscope. The α-ferrite ...

Coal-fired power plant is the largest anthropogenic mercury source. Active carbon injection technique has been widely used to control the mercury emissions. However, high operation cost limits its development and it is necessary to find other potential mercury sorbents. In this study, raw semi-coke and a series of novel cerium (Ce) modified semi-cokes were synthesized and utilized for removing elemental mercury (Hg0) from simulated flue gas. It is noteworthy that the efficiencies were tested without hydrogen chloride (HCl) in order to evaluate the sorbents efficacy for low-chlorine (Cl) coal. The results show that the modified sorbents exhibited the best performance at 150 °C. The performance of sorbent could be reinforced due to the existence of oxygen (O2), nitric oxide (NO) and HCl. The adverse effect caused by sulfur dioxide (SO2) reduced dramatically after Ce modification. The negative impact of ammonia (NH3) on Hg0 removal in this study could be neglected owing to the tiny concentration of NH3. Raw semi-coke provided sufficient carbon content, which is favorable to mercury adsorption. As Ce loading increased, the carbon structure changed and the crystal of cerium oxide was formed in the modified semi-coke. The mass fraction of cerium oxide on the sorbent was over 4.4% when the concentration of Ce modification solution was higher than 0.2 mol L−1. The redox reaction activity and the oxygen storage ability of Ce3+/Ce4+ gave a huge boost to the performance of modified semi-coke. The addition of Ce also had an impact on the proportion of oxygen species.

Rare earth oxides usually play an active role in modifying the microstructure and oxidation resistance of silicide coatings, but its modification mechanism has not yet been clarified. In this work, molybdenum silicide (MoSi2) coating with different contents of ytterbium oxide (Yb2O3) was fabricated using supersonic atmospheric plasma spraying, and its microstructural evolution and oxidation behavior were investigated. Experimental results shown that the morphological characteristics of produced SiO2-rich glass scale varied with the doping of Yb2O3, which noticeably affected the oxidation resistance of sprayed MoSi2-Yb2O3 coatings. All coated specimens exhibited a parabolic oxidation behavior, wherein the MoSi2-10 wt%Yb2O3 coating possessed the smallest parabolic constant and the lowest specific mass loss with 100 h oxidation at 1500 °C due to the absence of SiC-depleted region and the formation of continuous multicomponent compound scale. Given this, Yb2O3 additive with proper concentration not only guaranteed the sufficient filling of open spaces in SiO2 network by Yb3+ cations, but also strengthened the Si–O bonds to increasing the viscosity of SiO2 glass, thereby delaying the effective delivery of reactive oxygen species inwardly.

Porous structured silicon has been regarded as a promising candidate to overcome pulverization of silicon-based anodes. However, poor mechanical strength of these porous particles has limited their volumetric energy density towards practical applications. Here we design and synthesize hierarchical carbon-nanotube@silicon@carbon microspheres with both high porosity and extraordinary mechanical strength (>200 MPa) and a low apparent particle expansion of ~40% upon full lithiation. The composite electrodes of carbon-nanotube@silicon@carbon-graphite with a practical loading (3 mAh cm−2) deliver ~750 mAh g−1 specific capacity, 92% capacity retention over 500 cycles. This work is a leap in silicon anode development and provides insights into the design of electrode materials for other batteries., The authors here construct hierarchical porous CNT@Si@C microspheres as anodes for Li-ion batteries, enabling both high electrochemical performance and excellent mechanical strength. The work highlights the importance of mechanical properties in developing battery materials for practical applications.

The solubility of N-acetyl-l-leucine in 12 mono organic solvents (methanol, ethanol, n-propanol, 2-propanol, 1-butanol, isobutanol, 2-butanol, methyl acetate, ethyl acetate, propyl acetate, acetone...

The solubility of ceftiofur sodium trihydrate (CST) in binary solvent mixtures of water + acetonitrile, water + ethanol, water + n-propanol, and water + iso-propanol at temperatures from 273.15 to 313.15 K (P = 0.1 MPa) was measured by a laser dynamic method. The experimental results show that the solubility is positively correlated with temperature. In the four binary solvent systems, the solubility value of CST initially increases first and then decreases with increasing organic solvent composition. The maximum solubility values occur in the molar content of organic solvent of about 0.5 for water + acetonitrile, 0.5 for water + ethanol, 0.4 for water + n-propanol, and 0.4 for water + iso-propanol. The accuracy of experimental results was examined by the Apelblat model, the Van’t-JA model, and the Apel-JA model, and the Apelblat model shows the best fitting performance.

Recently, text style transfer has become a very hot research topic in the field of natural language processing. However, the conventional text style transfer is unidirectional, and it is not possible to obtain a model with multidirectional transformations through training once. To address this limitation, we propose a new task called multidirectional text style transfer. It aims to use a single model to transfer the underlying style of text among multiple style attributes and keep its main content unchanged. In this paper, we propose Unified Generative Adversarial Networks (UGAN), a practical approach that combines target vector and generative adversarial techniques to perform multidirectional text style transfer. Our model allows simultaneous training of multi-attribute data on a single network. Such unified structure makes our model more efficient and flexible than existing approaches. We demonstrate the superiority of our approach on three benchmark datasets. Experimental results show that our method not only outperforms other baselines, but also reduces training time by an average of 13%.

黑龙江小多宝山Fe-Cu矿床是多宝山-三矿沟多金属成矿带内一典型的矽卡岩型矿床。根据矿物共生组合及矿脉穿切关系，将其成矿作用划分为两期：矽卡岩期和石英-硫化物期；进一步划分为五个阶段：石榴子石-辉石干矽卡岩阶段；绿帘石-阳起石等含水硅酸盐湿矽卡岩阶段；磁铁矿-镜铁矿-石英氧化物阶段；黄铁矿-黄铜矿-石英早期硫化物阶段以及方铅矿-闪锌矿-方解石晚期硫化物阶段。本文报道了该矿床成矿岩体花岗闪长岩的锆石U-Pb年龄、全岩地球化学及锆石Hf同位素数据。花岗闪长岩锆石加权年龄为176±1Ma（MSWD=0.10，n=23），反映小多宝山矿床成矿时代为早侏罗世。其岩石地球化学特征表现为：富钠（Na2O/K2O=1.45%~1.63%），准铝质（A/CNK=0.92~0.97），富集轻稀土元素（LREE）、大离子亲石元素（如Rb、Ba、Sr、K等），相对亏损高场强元素（如Ta、Nb、Ti等），（La/Yb）N=11.16~12.87，表现出弱的负Eu异常（δEu=0.85~0.92），显示出岛弧岩浆岩的地球化学亲缘性。综合岩石地球化学及同位素测试结果，小多宝山花岗闪长岩为准铝质高钾-钙碱性I型花岗岩，起源于幔源岩浆结晶分异作用。锆石Hf同位素eHf（t）为+7.6~+11.4，二阶段模式年龄（tDM2）为492~732Ma，指示其岩浆源区为古生代新生地壳的熔融。结合区域构造演化，推断小多宝山花岗闪长岩形成于古太平洋板块俯冲的构造环境。

As the integration of wind power into electrical energy network increasing, accurate forecast of wind speed becomes highly important in the case of large-scale wind power connected into the grid. In order to improve the accuracy of wind speed forecast and the generalization ability of the model, Extreme Gradient Boosting (XGBoost) as an improvement from gradient boosting decision tree (GBDT) is trained and deployed in the cheaper central processing unit (CPU) devices instead of graphics processing unit (GPU) devices, thus, a wind speed forecast model based on Extreme Gradient Boosting is proposed in this paper. Firstly, the historical data is taken as a part of the input vectors for the model. Moreover, considering the monthly change of wind speed characteristics, the dataset of wind power is divided into four parts by month so that the models are constructed in different complexity by month. Finally, compared with back propagation neural networks (BPNN) and linear regression (LR) models, the experimental results show that the improved XGBoost model can promote the forecast accuracy effectively.

Time-optimal (TO) control is promising in many fields since it ensures to accomplish a task in minimum time. However, its direct application may cause oscillations or even limit cycles due to the restriction of the sampling period, state measurement accuracy and so on. To solve these problems, a compound proximate time-optimal (PTO) control law is proposed by considering system bandwidth and saturation in this paper. With the help of the phase plane, the switching zone and linear zone of the PTO control law are constructed. When the system state lies outside of both switching and linear zones, the bang-bang optimal scheme is adopted to achieve rapidity. And when the system state enters the switching zone, the bang-bang suboptimal scheme is developed to avoid oscillations or even limit cycles. Proportional-derivative (PD) scheme is applied in the linear zone to obtain local asymptotic stability around the origin. Numerical simulations are carried out to corroborate the advantages of the PTO control law.

Lithium metal is a potential candidate for next-generation anode materials. However, the practical application of a lithium metal anode has been hindered by uncontrolled dendrite formation. Herein, a cost-effective single lithium ion conducting polymer electrolyte membrane based on a highly porous lithium sulfonated polyether ether ketone electrospun nanofiber membrane (es-LiSPCE) is designed to serve as both a separator and a lithium ion conductor. Impregnation of the ethylene carbonate (EC)/dimethyl carbonate (DMC) (v/v = 1 : 1) solvent mixture and 1 M LiFP6 in EC/PC (v/v = 1 : 1) yields gel pure es-LiSPCE and es-LiSPCE/1 M LiFP6 in an EC/PC (v/v = 1 : 1) membrane, respectively, which display high ionic conductivity, low interfacial compatibility and a high lithium ion transference number. Combined scanning electron microscopy (SEM) images and the long-term stripping/plating cycling test of lithium foil confirm that such a membrane is greatly favorable for inhibiting the formation of a concentration gradient and thus suppressing lithium dendrite growth. In addition, the fully aromatic polyether ether ketone backbone enables high thermal dimensional stability and high polarity and high polarity enables fast electrolyte wetting of the es-LiSPCE membrane. Notably, Li/LiFePO4 cells fabricated using es-LiSPCE membranes demonstrate promising rate capacity at 6C, and excellent electrochemical stability for 1500 cycles even at 6C. Therefore, it is believed that such an electrolyte can serve as an alternative to conventional polyolefin-based separators for high energy density lithium metal batteries.

By using La(NO3)3•6H2O, Ca(NO3)2•4H2O, and Mn(CH3COO)2•4H2O as starting raw materials together with methanol, three kinds of La0.67Ca0.33MnO3 (LCMO) solutions, denoted as LCMO–BzAc, LCMO–AcAc, and LCMO–BPY, respectively, were obtained. The samples were fabricated via the photosensitive solution method with benzoylacetone (BzAc), acetylacetone (AcAc), and 2, 2′-bipyridine (BPY) as chelating reagents. The chelation mechanism of the metal ions was investigated via ultraviolet spectroscopy. The photosensitive compounds were decomposed after UV exposure and their products reduced the solubility of the LCMO gel films in organic solvents. The patterned LCMO thin films were then fabricated by using the self-photosensitive properties of their gel films. Through the mask micromachining process, the LCMO micropatterns prepared by using the LCMO–BzAc solution exhibited the highest quality. Moreover, they also presented good performance when the mask-free method was employed. The magnetic properties of the micropatterned LCMO films were investigated in detail and the results revealed that the micropatterning did not influence their saturation magnetization.