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[Display omitted] • The preparation mechanism of P-SiNPs/Ag@C was discussed in detail. • Anode materials derived from deposited silicon waste toward LiBs. • Electrochemical performance of P-SiNPs/Ag@C anode was investigated. Owing to the rapid advancement of the photovoltaic industry, a lot of photovoltaic (PV) silicon waste will be generated. Thus, the recycling and reuse of waste silicon have become particularly important, both for environmental remediation and economic benefits. In this work, a special structure of porous Si nanoparticles embedded nano-Ag and coated carbon layer (P-SiNPs/Ag@C) was produced by silver-assisted chemical etching (Ag-ACE) the deposited silicon waste. The special porous structure and carbon layer coating can effectively address the volume expansion issues during charge/discharge. The intercalated Ag nanoparticles greatly reduced the transfer impedance and enhanced the electrical conductivity of the anode material. As a result, the novel-designed P-SiNPs/Ag@C anode can maintain a prominent reversible capacity (1521 mAh·g−1 at 0.2 A g−1 after 50 cycles) and outstanding rate performance (1099 mAh·g−1 at 2 A g−1). When the current density at 1 A g−1, the specific capacity still maintains at 706 mAh·g−1 over 300 cycles. The superiority of the prepared P-SiNPs/Ag@C structures was further confirmed by Comsol Multiphysics software. Impressively, the synthesis route provides a novel avenue for value-added utilization of residual silicon waste resources from EB refining silicon and the preparation of high-performance lithium battery silicon-based anode. [ABSTRACT FROM AUTHOR]

With the increasing complexity of the power grid, the precision of the thermal power units' execution of automatic generation control (AGC) commands is gradually increasing the impact on the online regulation of the power grid. The deviation between the actual output of thermal power units and the AGC command of the grid will not only affect the consumption of new energy output, but also endanger the safe operation of the grid. This paper introduces "deep learning" technology to solve the problem. Firstly, an AGC command execution effect identification and confidence evaluation algorithm (ACEEI-CEA) is proposed. The algorithm builds a neural network model to accurately predict the unit output and the confidence evaluation of the prediction results. Next, a high-dimensional input preprocessing strategy based on variational autoencoder (VAE) is proposed to reduce the dimensionality of the model input attributes, improving the convergence and accuracy of the model. Finally, an AGC optimal command fast inversion solution method (AOCFISM) is designed. This method transforms the unit output deviation problem into an objective optimisation problem. And improve the efficiency of solving the optimal AGC command value by constraining the unit command value. The calculation results show that the error of the prediction results of the model proposed in this paper is 5% lower than that of the traditional neural network. The difference between the output value of the optimal AGC command and the expected output value obtained is less than 0.5 MV, which can support AGC online decision-making.© 2017 Elsevier Inc. All rights reserved. • An AGC command execution effect identification and confidence evaluation algorithm (ACEEI-CEA) is proposed. • Results show the ACEEI-CEA performs well in command prediction compared to the state-of-the-art methods. • ACEEI-CEA achieves confidence assessment of predicted values. • The pre-processing strategy based on variational autoencoder shortens the training time of the model. • The AGC optimal command fast inversion solution method (AOCFISM) can obtain the AGC optimal command value. [ABSTRACT FROM AUTHOR]

China's energy conservation has received extensive attention. As the most important sector of the economy, the manufacturing industry plays a vital role in China's energy issues. Conserving energy in China's manufacturing industry (CMI) is of great significance for both China and the world. In this paper, the co-integration method is applied to test the long-term equilibrium relationship among energy consumption and three explanatory variables during the period 1980–2013. Furthermore, we use scenarios analysis method to forecast the energy demand of CMI. The results show that if the government does not properly manage the economy, the energy demand of CMI will reach 2558.97 Mtce in 2020 and 2594.18 Mtce in 2030. On the contrary, if the government attaches importance to energy conservation and takes necessary actions, energy demand in the industry will reduce to 1113.79 Mtce by 2030, which implies a large energy conservation potential for CMI. [ABSTRACT FROM AUTHOR]

The development of inexpensive and high-performance bifunctional electrocatalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is of crucial significance for rechargeable metal-air batteries, but remains challenging. Herein, we report an ingenious bifunctional oxygen electrocatalyst integrating ZIF-derived carbon-anchored Fe/Ni single atoms, FeNi alloy nanoparticles, and graphene support (denoted as Fe/Ni-NC||FeNi@G). Synergizing highly active Fe single atoms for the ORR and highly efficient FeNi alloy nanoparticles for the OER, the as-constructed Fe/Ni-NC||FeNi@G catalyst exhibits outstanding bifunctionality; the potential gap between the OER potential at 10 mA cm–2 and the ORR half-wave potential is only 0.618 V, outperforming the benchmark Pt/C + Ir/C catalyst and most transition metal-based bifunctional catalysts reported in the literature. More importantly, the Fe/Ni-NC||FeNi@G-driven zinc-air battery (ZAB) delivers a maximum power density of ∼200 mW cm–2, a specific capacity of 876 mAh g–1, and excellent cycling stability with negligible voltage decay up to 500 hours (3000 cycles). This work provides an effective approach to designing highly efficient non-noble metal multifunctional catalysts for practical applications in rechargeable metal-air batteries. [ABSTRACT FROM AUTHOR]

The use of a small amount of MgO dopant can help to improve the performance of Na-β″-Al 2 O 3 electrolyte by enhancing the relative density, promoting the formation of homogeneous and compact microstructure, and increasing the content of β″-Al 2 O 3 phase. In this work, the effects of the amount of MgO dopant and the sintering temperature on the relative density, β″ phase content, and performance of the Na-β″-Al 2 O 3 electrolyte were studied in detail, respectively. The samples were characterized in respects of relative density, closed-cell porosity, XRD, SEM, bending strength, and AC Impedance. The results demonstrated that the addition of MgO dopant significantly improved the densification rate of Na-β″-Al 2 O 3 ceramics. The crucial temperature phase for pore elimination was 1500–1550 °C. Samples doped with 0.2–2.0 wt% MgO formed homogeneous microstructures associated with grain size refinement of the final compact at 1550 °C. Macro defects appeared when sintering temperature reached to 1580 °C. The total conductivity showed a linear dependence on the temperature (200–700 °C), which fitted well with the Arrhenius equation. Na-β″-Al 2 O 3 ceramics doped with 0.4 wt% MgO showed the best bending strength (283 MPa) and preferable ionic conductivity. [ABSTRACT FROM AUTHOR]

Background: We retrospectively analyzed risk factors for late bronchopleural fistula after non-small cell lung cancer (NSCLC) surgery and compared with those for early bronchopleural fistula. Methods: In all, 6,239 patients with NSCLC who underwent surgery were studied, and clinical risk factors were examined by univariate and multivariate analysis. This study included 23 patients (0.38%) with late bronchopleural fistula and 43 patients (0.65%) with early bronchopleural fistula among all 6,239 patients. Follow-up data were recorded until December 2005 or until death. Statistical significance was calculated using the log rank test. Results: By univariate analysis, patients with radiotherapy after operation, pneumonia after operation, pneumonectomy, and advanced age were related to higher risk of bronchopleural fistula. In the multiple logistic regression models, both pneumonia and operative procedure were among the independent risk factors of early and late bronchopleural fistula. Early bronchopleural fistula was observed primarily in the aged. Late bronchopleural fistula was associated with postoperative radiotherapy. The average intervals of bronchopleural fistula between pneumonectomy and lobectomy were significantly different. Compared with the mortality rate of late bronchopleural fistula (0%), the mortality rate of early bronchopleural fistula (11.6%) was significantly higher. Conclusions: There are both similarities and differences between the risk factors for early and late bronchopleural fistula. We should analyze the different reasons for the occurrence of bronchopleural fistula, and adopt different preventive measures. Different follow-up should be provided for the different operations. [Copyright &y& Elsevier]

Precisely engineering the composition and structure of nanomaterials can effectively tune their activity and stability towards oxygen reduction reaction (ORR), a key process in fuel cells. Here, a highly active and stable electrocatalyst for ORR is fabricated by alloying Ni atoms with octahedral Pt–Pd nanocages with ultrathin walls and exposed (111) facets. The specific activity (3.8 mA/cm2) and mass activity (1.17 A/mg Pt) of the octahedral Pt–Pd–Ni nanocages represent a performance enhancement by a factor of 25 and 10 compared to commercial Pt/C, respectively. In addition, the ORR activity of octahedral Pt–Pd–Ni nanocages significantly outperforms the octahedral Pt–Pd nanocages (1.89 mA/cm2 and 0.73 A/mg Pt in specific and mass activity). The ligand effect and compressive strain, confirmed by the X-ray absorption fine structure (XAFS) analysis and density functional theory (DFT) calculations, accounts for the enhanced activity by weakening the adsorption energy of hydroxyl groups. Particularly, it shows robust stability with only 16% decay in the mass activity after accelerating degradation tests (ADTs), rationalized by its structural stability and high vacancy formation energy. This work provides a new class of Pt based nanocatalysts with high activity and stability for ORR. Trimetallic Pt–Pd–Ni octahedral nanocages with ultrathin wall for oxygen reduction reaction are synthesized. This material shows superior mass and specific activity (1.17 A/mg Pt and 3.8 mA/cm2) and robust stability for ORR. The compressive strain effect and high vacancy formation energy accounts for the high activity and stability of the trimetallic Pt–Pd–Ni octahedral nanocages. Image 1 • Trimetallic octahedral Pt–Pd–Ni nanocages were firstly synthesized as electrocatalysts for oxygen reduction reaction. • The mass activity of the Pt–Pd–Ni octahedral nanocages at 0.9 V achieved a factor of 10 enhancement compared to commercial Pt/C. • The Pt–Pd–Ni nanocages showed a greatly enhanced stability. • The enhanced mechanism on the Pt-Pd-Ni octahedral nanocages have been investigated by the combination of advanced XAS spectrum and DFT calculation. [ABSTRACT FROM AUTHOR]

• A strategy for the Si recovery and Al removal from DWSSP was proposed. • The main impurity Al in DWSSP was derived from perlite filter aid. • The introduction of Na 2 CO 3 can create impurity-trapped LPS-layer on DWSSP. • The elimination mechanism of impurity Al from DWSSP-ceramic was studied. • The strategy has the potential for DWSSP utilization in the PV industry. Recycling diamond wire sawing silicon powders (DWSSP) from photovoltaic (PV) silicon wafers production has become an urgent problem. The challenge of recovery is the surface oxidation and contamination of the ultra-fine powder with impurities during the sawing and collection process. In this study, a clean recovery strategy of Na 2 CO 3 -assisted sintering and acid leaching was proposed. Due to the Al contamination from the perlite filter aid, the introduced Na 2 CO 3 sintering aid can react with the SiO 2 shell of DWSSP to form a slag phase with accumulated impurity Al during the pressure-less sintering process. Meanwhile, the evaporation of CO 2 contributed to the formation of ring-like pores surrounded by a slag phase, which can be easily removed by acid leaching. When 15 % Na 2 CO 3 was added, the content of impurity Al in DWSSP could be reduced to 0.07 ppm with a removal rate of 99.9 % after acid leaching. The mechanism suggested that the addition of Na 2 CO 3 can trigger the liquid phase sintering (LPS) process of the powders, and the cohesive force and liquid pressures difference generated during the process facilitated the transportation of impurity Al from the SiO 2 shell of DWSSP to the formed liquid slag phase. The efficient silicon recovery and impurity removal of this strategy demonstrated its potential for solid waste resource utilization in the PV industry. [ABSTRACT FROM AUTHOR]

• A 3D steady-state FE model was developed for thermal analysis of hybrid plasma arc-laser additive manufacturing. • Artificial conductivity in three orthogonal directions was applied in the melt pool to compensate for the melt pool convection effect. • This model has advantages over the commonly used volumetric heat source models. • The melt pool geometry at different process conditions was analysed. • The full-field distributions of the cooling rate and thermal gradient were obtained. Hybrid plasma transferred arc (PTA)-laser additive manufacturing (AM) has the potential to build large-scale metal components with high deposition rate and near-net shape. However, the process is complex with many parameters adjustable for process control, which determine the thermal behaviour and thus the final structure and properties of the deposited components. In this study, a three-dimensional steady-state finite element model with two independent circular surface heat sources was developed, validated, and used to analyse the thermal behaviour in hybrid PTA-laser AM of Ti-6Al-4V. Artificial conductivity in three orthogonal directions was applied in the melt pool to compensate for the melt pool convection effect. The predicted melt pool geometry, heat-affected zone and thermal cycles had good agreement with the corresponding experimental data. This model has advantages over the widely used volumetric heat source model, since it is more representative of the energy sources used, giving accurate thermal prediction for a wide range of process parameters. As the heat source parameters in this model are directly linked to the actual arc/laser size, it enables to capture heat source size effect on the hybrid process. In addition, it is easier to calibrate compared to the model with volumetric heat sources due to the fewer empirical parameters involved. It was found that in the investigated ranges of all the parameters, the melt pool geometry is more sensitive to laser power and travel speed compared to arc-laser separation distance and laser beam size. The full-field distributions of the cooling rate and temperature gradient in the hybrid process were obtained and the roles that different process parameters played on them were also studied, which provided useful thermal information for metallurgical analysis. [ABSTRACT FROM AUTHOR]

• Recoil pressure is the key factor for spattering and expansion of molten pool. • Intensity of vortex generated at groove bottom is greater than that at the side. • More recast layer and redeposition of melt result in a poor surface roughness of groove. • Surface roughness of groove gradually decreased with increasing laser moving speed. Laser surface texturing is considered as a novelty and feasible technology to fabricate some micro-feature due to the non-contact, high precision and processing efficiency. However, it is difficult to deeply understand the material removal mechanism and predict the surface topography due to a confined heat-affected zone and extremely short time in the laser machining process. In this research, based on the mixed phase theory and level-set method, a modified heat-mass transfer and hydrodynamic model was proposed for deeply analyzing the influence of various physical factors such as recoil pressure, buoyancy, surface tension, gravity and thermal-mass transport on the material removal and micro-texture topography evolution at a mesoscale level. The analysis of hydrodynamic behaviors and temperature fields of the molten pool indicated that the melts sputtering and molten pool expansion caused by the recoil pressure was the dominant factor responsible for micro-texture formation during laser action. The reflux induced by the surface tension and gravity as well as the residual effect of the melts flowing upward were the main factors of the occurrence of a vortex during the molten pool cooling. Finally, the effects of laser parameters on the micro-feature topography were discussed based on the experiments and simulation model. The diameter and depth of the hole as well as the width and depth of the groove gradually increased with increasing frequency and pulse duration. The laser moving speed had less effect on the width of the groove, but it had great effect on the surface roughness of the groove. This work can be beneficial to understand the material removal mechanism and provide a guide for the parameters optimization of laser processing at a mesoscale level. [Display omitted] [ABSTRACT FROM AUTHOR]

A novel red thermally activated delayed fluorescence (TADF) emitter, 2-(4,4″-bis(diphenylamino)-[1,1':3′,1″-terphenyl]-4′-yl) quinoxaline-6,7-dicarbonitrile (QCN-2TPA), was developed by incorporating two trianiline units into the ortho- and para-positions of the quinoxalin-6,7-dinitrile core. The adjacent trianiline unit and quinoxalin-6,7-dinitrile core interact spatially for through-space charge transfer, while the quinoxalin-6,7-dinitrile core and the para-positioned trianiline unit enable through-bond charge transfer. QCN-2TPA demonstrated high photoluminescence quantum efficiency and a small Δ E ST. Organic light-emitting diodes using QCN-2TPA as the emitter achieved a maximum external quantum efficiency of 21.4 % with red emission peaking at 596 nm. [Display omitted] • The novel emitter simultaneously demonstrates both TSCT and TBCT characteristics. • The emitter shows red emission with distinct TADF property. • The QCN-2TPA -based OLED achieves a higher EQE of 21.4 % compared to its counterparts. [ABSTRACT FROM AUTHOR]

By using ERA-I reanalysis data and the reforecast and forecast data of NCEP CFSv2, the inter-decadal shift in the stratospheric polar vortex boundary in winter and autumn in the Northern Hemisphere since the 1980s is analyzed, and the ability of CFSv2 to simulate the polar vortex boundary is evaluated. The results show that from 1980 to 2017, the Arctic polar vortex retreated northward in North America and expanded southward in Eurasia in winter, but the polar vortex expanded in North America and retreated in Europe in autumn. The polar vortex expanded significantly from the 1980s to the 2000s and retreated in the 2010s in Asia. In winter, the retraction of the polar vortex occurred mainly in the 1990s in North America, and the expansion of the polar vortex occurred mainly in the 2000s in Europe and in the 1990s in Asia. In autumn, the southern expansion of the polar vortex boundary in North America mainly occurred in the 1990s, the retraction of the polar vortex in Eurasia occurred in the 2010s. The overall trend of the winter polar vortex boundary and area simulated by CFSv2 is consistent with that simulated by the ERA-I data in the 1980–2010s, especially for the expansion trend in North America and Asia in the 2010s. The simulation of the boundary and area of the polar vortex by the CFSv2 in autumn is poorer than that in winter; the simulation of the overall trends in the polar vortex boundary and area change is poor. • At present, there are few studies on changes of the polar vortex boundary in autumn. • In winter, the Arctic polar vortex retreated northward in North America and expanded southward in Eurasia. • In this paper we analyzed and evaluated the simulation level of the stratospheric polar vortex shift events. • The simulation of the boundary and area of the polar vortex by the CFSv2 in autumn is poorer than that in winter. [ABSTRACT FROM AUTHOR]

• Nonaqueous HEMA-DEGDA gelation system is developed to form Li-BASE green body. • Plasticizer is successfully used to eliminate cracks and warpage in the green body. • Perfect gelcast of Li-BASE is obtained with mechanical strength of 17 MPa. • Sintered gelcast of Li-BASE exhibits good mechanical and electrical properties. A novel non-aqueous gelcasting system based on the polymerization of 2-hydroxyethyl methacrylate (HEMA) with low toxicity is applied to the fabrication of lithium stabilized beta alumina solid electrolyte (Li-BASE). Triethanolamine and polyethylene glycol (MW. 1000) are used as dispersant and plasticizer, respectively. Effects of dispersant concentration, solids loading and plasticizer concentration on the rheological behavior of the suspensions are investigated and optimized. Cracking and warpage phenomena in the gelcast green body during drying process are discussed. Green body gelcast from the optimized suspension shows homogeneous microstructure with a relative density of 59.4 % and a bending strength of 17 MPa. Properties, including the relative density, phase composition, microstructure, bending strength and ionic conductivity, of Li-BASEs sintered from green body formed by gelcasting and cold isostatic press are evaluated. Results show that gelcasting forming technique performs well in preparing BASE ceramics with high Weibull modulus and ionic conductivity. [ABSTRACT FROM AUTHOR]

Abstract In this study, investigations of sintering behavior and properties were performed on lithium-stabilized Na-β''-alumina (LiSBA) ceramics with and without 15 wt% 8 mol% Y 2 O 3 stabilized ZrO 2 (8YSZ) addition synthesized by solid phase reaction. Changes of phase composition, relative density, and grain size in the ceramics sintered at different temperature were analyzed. It was shown that phase transformation in sintering ceramics was controlled by relationship between the Na 2 O evaporation and Li+ ions stabilization, while microstructure evolution was controlled by pore-boundary interaction. LiSBA with YSZ addition (Zr-LiSBA) showed more significant variation of β'' phase fractions, slower grain growth and faster densification with increasing sintering temperature, which were caused by enhanced Na 2 O evaporation and gas transport by oxygen ion conductor ZrO 2 as well as the drag effect by second phase particles of YSZ in Zr-LiSBA ceramics. Zr-LiSBA specimens sintered at optimized condition achieved higher Vickers microhardness and intermediate Na+ ion conductivity. [ABSTRACT FROM AUTHOR]

Accumulating researches identify microRNA-26a (miR-26a) as a tumor suppressor in hepatocellular carcinoma (HCC). F-box protein 11 (FBXO11), a predicted target gene of miR-26a, is an E3 ubiquitin ligase and a type II methyltransferase, and functions as a key regulator of tumor initiation and progression. This study was aimed to investigate the regulatory role of miR-26a in FBXO11 expression and explored the clinical significance as well as functional role of FBXO11 in HCC. The expression levels of miR-26a were prominently downregulated in HCC tissues compared to matched tumor-adjacent tissues. MiR-26a inversely regulated FBXO11 abundance in HCC cells. Hereby, miR-26a could directly target 3′UTR of FBXO11 mRNA to suppress its expression. Gene Expression Omnibus (GEO) database (GSE54236 and GSE45436) and our data demonstrated that the expression of FBXO11 was up-regulated in HCC tissues. The level of FBXO11 mRNA was inversely correlated with miR-26a expression in HCC specimens. High FBXO11 expression was positively correlated with large tumor size, venous infiltration and advanced tumor stage of HCC patients. Clinical prognostic analysis illustrated that high FBXO11 expression predicted a poor survival of HCC patients. In vitro , FBXO11 knockdown inhibited cell proliferation, colony formation, migration and invasion of HCC cells. Additionally, miR-26a overexpression showed a consistent effect with FBXO11 knockdown on these malignant behaviors of HCC cells. Notably, FBXO11 restoration reversed the inhibitory effect of miR-26a on HCC cell proliferation, colony formation, migration and invasion. In summary, these results indicated that miR-26a regulation of FBXO11 exhibited an oncogenic role in HCC. Inhibition of FBXO11 might serve as a therapeutic target for HCC. [ABSTRACT FROM AUTHOR]

The humidity property of the lithium stabilized Na-β"-alumina (LSBA) sensing material was investigated in detail on a resistivity-type sensor prepared by pasting LSBA powder on a ceramic substrate with Ag interdigitated electrodes through ac and dc analysis. Results from ac complex impedance analysis suggested that LSBA powder based sensor was highly sensitive to humidity with a six order magnitude impedance difference as relative humidity (RH) changed from 11.3% to 93.6% and good stability in 30 days. The response time and recovery time of the sensor were short at lower RH circumstance, which were 42 s and 48 s at 52.8% RH, respectively. Evidences from dc variation, ac dielectric loss and ac complex impedance spectra under different RH circumstance indicated that high humidity sensitivity of the LSBA sensor originated not only from the water molecules absorbed on the surface but also from the Na + ions in the conduction slab of the LSBA crystal. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new arc and friction stir hybrid welding process was successfully developed to join aluminum to steel. • Optimizing the BC-MIG welding process parameters could reduce the thickness of brittle intermetallic compound layer to within 1.5 μm. • The hybrid welded joints provided superior mechanical properties with fractures in the aluminum base metal. • The relationship between microstructure, mechanical strength and fracture mechanism was analyzed. In this study, arc and friction stir hybrid welding (AFSHW) was proposed to weld aluminum-steel dissimilar metals in attempt to realize high quality joining. Firstly, an interlayer was produced on galvanized steel by using bypass current-metal inert gas welding (BC-MIG), and then an aluminium plate was jointed via Friction stir lap welding (FSLW). The effects of tool pin length and FSLW times on the microstructure and mechanical properties of dissimilar joints were fully investigated by means of Optical Microscopy (OM), Scanning Electron Microscope (SEM), Electron Backscatter Diffraction (EBSD), and mechanical testing. The results show that as pin length increased, joint strength tended to increase and then decrease, and the tensile failure partially occurred at aluminium base metal. However, with additional number of FSLW, joint strength would be reduced, which was attributed to attenuated dislocation density and strain concertation in dissimilar joint. The research outcomes will provide a new welding method to obtain sound Al-Fe dissimilar metal joint, and benefit to a better understanding of Al-Fe joining mechanism. [ABSTRACT FROM AUTHOR]