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• The virtual fabric model can be used for the simulation of actual weaving process. • Virtual fabric composed of truss elements predicts the microstructure of 3D woven fabric. • Friction and yarn tension affect the trajectory and cross-sectional shape of the yarn. • The intersection-induced tension between warp and weft yarn causes fabric deformation. • The corners of the mold induce the interlayer slippage of fabric and alter the trajectory of the warp yarns. This article introduces a modeling method aimed at predicting the internal geometric structure of 3D warp interlock fabric. Inspired by the digital element method, the method employs truss elements to model the yarns as fiber bundles, and considers their material properties. This technique allows for predicting the microstructure of 3D woven fabric based on simple input characteristics. By varying the elastic modulus of virtual fibers, the friction coefficient between fibers, and the tension load at the ends of yarns, and designing compression molding molds to compress the fabric into shape, the virtual fiber fabric predicted the influence of variables on the fabric. The study found that the structure of the samples obtained through CT scanning is generally consistent with the structure of the virtual fiber fabric. The elastic modulus has a relatively minor impact on the fabric structure, whereas the friction coefficient and tension load significantly affect the cross-sectional shape of the yarns. During compression molding, deformation within the mold leads to interlayer fabric slippage and changes in the cross-sectional shape of the fabric. This suggests the feasibility and applicability of virtual simulation testing methods for analyzing the behavior of various types of 3D woven fabrics. [ABSTRACT FROM AUTHOR]

To solve the problems of poor exploration ability and convergence speed of traditional deep reinforcement learning in the navigation task of the patrol robot under indoor specified routes, an improved deep reinforcement learning algorithm based on Pan/Tilt/Zoom(PTZ) image information was proposed in this paper. The obtained symmetric image information and target position information are taken as the input of the network, the speed of the robot is taken as the output of the next action, and the circular route with boundary is taken as the test. The improved reward and punishment function is designed to improve the convergence speed of the algorithm and optimize the path so that the robot can plan a safer path while avoiding obstacles first. Compared with Deep Q Network(DQN) algorithm, the convergence speed after improvement is shortened by about 40%, and the loss function is more stable. [ABSTRACT FROM AUTHOR]

• Advantages of asymmetric hybridization on impact resistance and resilience. • Rules of external damage area and internal crack volume distribution. • Damage mechanism of carbon/Kevlar hybridization laminates. The ply structure has a significant effect on the impact resistance and failure behavior of composite laminates. In this paper, carbon/Kevlar hybrid fabric reinforcements were prepared with different Kevlar ratio (0%, 25%, 50%, 75%, 100%) by replacing carbon fabric plies on the non-impact side by Kevlar plies. The low-velocity impact tests for all configurations were carried out under 15 J and 25 J energy respectively. The results show that the maximum deflection, impact duration, impact absorption energy and absorption energy efficiency of hybrid laminates increased with the Kevlar hybrid ratio, whereas the peak force presented a decreasing trend, which indicates that the adding of Kevlar layer makes the laminates more ductile than non-hybrid carbon structure. The damage mechanism of the carbon fiber ply was brittle fiber fracture, resin cracking and resin shedding, while the fibers pull-out and tows splitting was found in Kevlar ply. The critical structural damages start from the non-impact side and evolve to the impact side. And the rules of internal crack volume distribution with Kevlar plies are consistent with the trend of external damage area on the non-impact side. It is suggested that in order to take into account the peak strength and excellent structural resilience, Kevlar asymmetric-hybrid ratio of 25% is the most appropriate. The reason is that an appropriate small ratio of Kevlar cushion ply can not only effectively avoid the tensile fracture at non-impact side happened in the non-hybrid carbon structure, but also withstand enough impact load by maintaining a high carbon fiber content. [ABSTRACT FROM AUTHOR]

[Display omitted] • Self-assembly by electrostatic interaction between silane and MOF ligand. • The activation mechanism of electrochemical inert metal Co in SiO x materials was investigated. • The catalytic action of atomic Co site activates Si O bond and Li O bond to increase SiO x capacity and coulomb efficiency. • High mechanical strength and high conductivity Co nanoparticles enhance the conductivity and cycling stability of SiO x. The ultra-high theoretical capacity of silicon-based (Si) materials makes them promising anode materials for high energy density lithium-ion batteries. Unfortunately, the dramatic volume change (∼300%) and low electrical conductivity of silicon have severely hindered the commercial use of silicon anodes. Silicon suboxide (SiO x) is one of the ideal candidates for high energy density batteries due to its reduced swelling and lower cost as compared to silicon. However, it remains a huge challenge to address the low conductivity, low (initial) coulombic efficiency and apparent volume effects of SiO x. In this paper, SiO x /Co@C composite anode materials loaded with metal Co nanoparticles were uniformly and efficiently prepared by using 3-aminopropyl triethoxysilane (APTES) as silicon source and Co-MOF as Co source via molecular self-assembly strategy. The experimental results and density functional theory (DFT) calculation showed that the catalytic action of embedded Co nanoparticles had activated the silico-oxygen bond of SiO x and the irreversible product Li 2 O, thereby improving the initial coulombic efficiency (ICE) and enhancing the reversible capacity. At the same time, the metal Co with mechanical rigidity and electrical conductivity alleviated the volume fluctuation during alloying and improved the charge transfer capacity and ion transport rate of the composite. When compared with SiO x @C anodes, SiO x /Co@C-600 composites showed higher initial CE, superior cyclic stability and good rate performance. In particular, the successful matching of the anode with the lithium iron phosphate (LFP) cathode in full cell systems validated the possibility of its practical application. This work provides important insights into the application of Si-based materials in lithium-ion battery electrode materials and the development of high energy density batteries. [ABSTRACT FROM AUTHOR]

• A temperature component is given by theoretical inference and parameter optimization. • Separate modeling technique is proposed based on ICEEMDAN and clustering analysis. • The ET-SMT-DELM model is established by a multi-output deep extreme learning machine. • The proposed model has high accuracy, credibility and interpretability. The anatomy of service status through health monitoring models is essential to long-term structural safety. Since deformation is the intuitive representation of the dam's operating condition, it is crucial to investigate the deformation monitoring model with high accuracy and strong interpretability for the safety management of high arch dams. A novel deformation monitoring model is proposed by incorporating impulse response-based equivalent temperature (ET) and machine learning-aided separate modeling technique (SMT). This methodology has three main sources of novelty. First, the impulse response-based equivalent temperature and corresponding temperature component are derived from heat transfer and temperature convolution theories. Then, the model parameters are identified by an improved firefly algorithm. Second, the components in the monitored displacement are progressively stripped out by clustering analysis, separation under equal water level conditions, and a robust signal decomposition technique. Third, the separated deformation components and environmental factors are modeled by the multi-output deep extreme learning machine (DELM) with autoencoder, and the monitoring model ET-SMT-DELM is thus established. The world's highest arch dam is selected to illustrate the proposed model, and the prediction accuracy, early warning performance, component shares, and impulse response mechanism are comprehensively investigated by comparing with several typical baseline models. The results show that the overfitting of the proposed model is reduced, and the prediction and early warning performance is significantly improved. The resulting temperature impulse response function and component shares imply that the interpretability of the model is also enhanced. [ABSTRACT FROM AUTHOR]

Hydrothermal liquefaction (HTL) of microalgae for bio-oil production is a promising strategy to avoid extensive fossil fuel utilization, while tandem amidation and Maillard reactions during hydrolysis of cellular compounds unavoidably result in formation of nitrogen containing (N-containing) compounds, reducing quality of bio-oil. Accordingly, VO 4 3− intercalated Cu–Fe layered double oxides named as Cu 2 Fe-VO 4 -LDO is firstly synthesized to both catalyze hydrolysis of cellular compounds and block N-containing compounds formation. The results indicate Cu 2 Fe-VO 4 -LDO can improve bio-oil yield from 19.32 to 20.32 wt%, with decrease of N/C ratio from 0.70 of control to 0.67 of experimental group, and increase of H/C ratio from 0.129 to 0.132. The insert of VO 4 3− provides more strong-acid sites, which are beneficial to hydrolysis of cellular compounds. Meanwhile, more strong-base sites of Cu 2 Fe-VO 4 -LDO promote decarboxylation of fatty acids and removing amino-group of amino acids, subsequently improve production of alkanes. Furthermore, the reversible oxidation of VO 4 3− promotes oxidation of reducing sugars, blocking tandem amidation and Maillard reaction between intermedia of hydrolyzed lipids, carbohydrates, and proteins. This work reports a methodology for synthesis of Cu 2 Fe-VO 4 -LDO with strong acid-base sites and reversible oxidize interlayer sites, providing a strategy to simultaneously improve bio-oil yield and reduce its N/C ratio. [Display omitted] • Intercalated of VO 4 3− provides stronger basic sites and reversible redox property. • Enhanced de-amino and oxidation of glucose leads to decrease of N/C from 0.70 to 0.67. • VO 4 3− favors decarboxylation, leading to increase of H/C from 0.129 to 0.132. [ABSTRACT FROM AUTHOR]

Accurately identifying various meso-morphological features and sub-phases within the damaged braided composite fabric is crucial for assessing the mechanical properties of composites under complex loading conditions and different processing parameters. However, obtaining 3D reconstructions that can be quantitatively analyzed is still a challenge, primarily due to the low contrast of the meso-morphological features (yarn tow and matrix crack networks). In this work, a new data enhancement algorithm is proposed to generate a realistic-looking artificial training dataset for enriching the information of the meso-morphological features. Then, the effect of various training networks and training parameters (the size of real and hybrid training dataset, number of epochs) on segmentation performance were examined. Finally, the meso-morphological features were statistically analyzed to accurately evaluate the mechanical properties of the composite material. The work presented here provides an effective tool that enables the quantitative analysis of the dynamic crack evolution process under the axial load of the composite materials. [Display omitted] [ABSTRACT FROM AUTHOR]

Spatial variability of tensile strength, widely existing in concrete gravity dams due to the influence of long construction period and heterogeneous construction quality, has a profound impact on the nonlinear behaviour of structures. In this paper, a method to simulate the random field of the tensile strength of concrete gravity dams based on the random field theory is proposed. A typical non-overflow dam section of the Guandi gravity dam is taken as an example, artificial seismic waves with similar response spectra and natural seismic waves with different magnitudes are selected for the comparative analysis. Based on the concrete damage plasticity (CDP) model and incremental dynamic analysis (IDA) method, the damage characteristics, failure modes, probability density evolution processes, and fragility curves obtained from gravity dams with homogenous and random fields of tensile strength are compared with each other. The differences among waves and realisations of random fields are also investigated. It is seen that the spatial variability of tensile strength aggravates the damage degree, decreases the continuity of local damaged areas, and increased the failure probability of global dams. It reveals that the random characteristics affect the dams' nonlinear behaviour directly. [ABSTRACT FROM AUTHOR]

ABSTRACT Based on Beijing-Arizona-Taiwan-Connecticut (BATC) and Sloan Digital Sky Survey (SDSS) photometric data, we adopt the spectral energy distribution (SED) fitting method to evaluate the metallicity distribution for ∼40 000 main-sequence stars in the Galaxy. According to the derived photometric metallicities of these sample stars, we find that the metallicity distribution shifts from metal-rich to metal-poor with the increase of distance from the Galactic Centre. The mean metallicity is about −1.5 ± 0.2 dex in the outer halo and −1.3 ± 0.1 dex in the inner halo and smoothly decreases from −0.4 to −0.8 in the interval 0 < r≤ 5 kpc. A fluctuation in mean metallicity with Galactic longitude can be found in the interval 4 < r≤ 8 kpc. There is a vertical abundance gradient d[Fe/H]/d z∼−0.21 ± 0.05 dex kpc−1 for the thin disc ( z≤ 2 kpc). At a distance 2 < z≤ 5 kpc, where thick-disc stars dominate, the gradient is about −0.16 ± 0.06 dex kpc−1; this can be interpreted as a mixture of stellar populations with different mean metallicities at all z levels. The vertical metallicity gradient is −0.05 ± 0.04 dex kpc−1 for the halo ( z > 5 kpc), so there is little or no metallicity gradient in the halo. [ABSTRACT FROM AUTHOR]

IR-drop is a fundamental constraint by almost all integrated circuits (ICs) physical designs, and many iterations of timing engineer change order (ECO), IR-drop ECO, or other ECO are needed before design signoff. However, IR-drop analysis usually takes a long time and wastes so many resources. In this work, we develop a fast dynamic IR-drop predictor based on a machine learning technique, XGBoost, and the prediction method can be applied to vector-based and vectorless IR-drop analysis simultaneously. Correlation coefficient is often used to characterize the symmetry of prediction data and golden data, and our experiments show that the prediction correlation coefficient is more than 0.96 and the average error is no more than 1.3 mV for two industry designs, which are of 2.4 million and 3.7 million instances, respectively, and that the analysis is speeded up over 4.3 times compared with the IR-drop analysis by commercial tool, Redhawk. [ABSTRACT FROM AUTHOR]

• Time to WBE results should be considered when evaluating early warning potential. • WBE early warning driven by differential in clinical and WBE reporting. • WBE early warning potential limited in situations with available and rapid clinical testing. Wastewater-based epidemiology (WBE) has emerged as a useful tool in the fight to track and contain COVID-19 spread within communities. One of the motives behind COVID-19 WBE efforts is the potential for 'early warning' of either the onset of disease in a new setting or changes in trends in communities where disease is endemic. Many initial reports of the early warning potential of WBE have relied upon retrospective sample analysis, and delays in WBE analysis and reporting should be considered when evaluating the early warning potential of WBE that enable public health action. Our purpose in this manuscript is to establish a framework to critique the potential of WBE to serve as an early warning system, with special attention to the onset of viral shedding and the differential between results reporting for WBE and clinical testing. While many uncertainties remain regarding both COVID-19 clinical presentation and technical factors influencing WBE results, our analysis suggests at most a modest lead time interval ranging from six days for clinical testing to four days for WBE during community-level wastewater surveillance where clinical testing is accessible on-demand with a rapid time to results. This potential lead time for WBE subsequently increases in settings with limited clinical testing capacity or utilization. Care should be taken when reporting 'early detection' of COVID-19 disease trends via WBE to consider underlying causes (e.g., clinical testing lag or delayed result reporting) to avoid misrepresenting WBE potential. [ABSTRACT FROM AUTHOR]

Abstract: Using Z-scan method with picosecond laser at 532nm, the third order optical nonlinearities of ZnFe2O4 were investigated. The nonlinear refractive index is positive for all ZnFe2O4 samples and decrease with the nanocrystal size. The nonlinear absorption dominated by saturable absorption for 19nm and 11nm ZnFe2O4 but by two photon absorption for 5nm ZnFe2O4 organosol. Origin of the optical nonlinearities and the size effect has been discussed. [Copyright &y& Elsevier]

Background and Aims. Hepatic encephalopathy (HE) is characterized by recurrence and poor quality of life. Acute-on-chronic liver failure (ACLF) mainly occurs in patients with chronic liver diseases and often presents with HE. Several predictive models have been proposed to predict the outcomes of these patients. Our study is aimed at identifying associated risk factors and the prognostic accuracies of predictive models in HE patients with or without ACLF. Methods. Patients with liver cirrhosis were retrospectively enrolled. Risk factors were evaluated by multivariate regression analyses. The predictive capabilities of models were calculated using the receiver operating characteristic (ROC) curve analyses and compared by the DeLong tests. Outcomes were defined as in-hospital mortality, HE severity, and ACLF occurrence. Results. In multivariate regression analyses, serum biomarkers neutrophil and total bilirubin (TBIL) were independently correlated with in-hospital death. Alanine aminotransferase (ALT) and blood urea nitrogen (BUN) were independent serum biomarkers associated with HE severity. Hemoglobin, TBIL, BUN, and international normalized ratio (INR) were significant indicators associated with ACLF incidence. For prediction of in-hospital mortality, Child-Pugh was superior to the others in the whole patients, while NLR showed the best capability in the ACLF group. Conclusion. In cirrhotic patients present with HE, BUN is a risk factor associated with HE severity and ACLF incidence. Child-Pugh and NLR scores may be effective prognosticators in patients with HE. [ABSTRACT FROM AUTHOR]

Both Kaposi's sarcoma-associated herpesvirus (KSHV) and Epstein-Barr virus (EBV) establish the persistent, life-long infection primarily at the latent status, and associate with certain types of tumors, such as B cell lymphomas, especially in immuno-compromised individuals including people living with HIV (PLWH). Lytic reactivation of these viruses can be employed to kill tumor cells harboring latently infected viral episomes through the viral cytopathic effects and the subsequent antiviral immune responses. In this study, we identified that polo-like kinase 1 (PLK1) is induced by KSHV de novo infection as well as lytic switch from KSHV latency. We further demonstrated that PLK1 depletion or inhibition facilitates KSHV reactivation and promotes cell death of KSHV-infected lymphoma cells. Mechanistically, PLK1 regulates Myc that is critical to both maintenance of KSHV latency and support of cell survival, and preferentially affects the level of H3K27me3 inactive mark both globally and at certain loci of KSHV viral episomes. Furthremore, we recognized that PLK1 inhibition synergizes with STAT3 inhibition to efficiently induce KSHV reactivation. We also confirmed that PLK1 depletion or inhibition yields the similar effect on EBV lytic reactivation and cell death of EBV-infected lymphoma cells. Lastly, we noticed that PLK1 in B cells is elevated in the context of HIV infection and caused by HIV Nef protein to favor KSHV/EBV latency. Author summary: KSHV is a large double-stranded DNA virus belonging to human gamma-herpesviruses and capable of establishing the long-term persistent infection, which causes cancers under immunocompromised states, such as acquired immunodeficiency syndrome (AIDS). There are currently still no effective therapies to specifically treat KSHV-associated tumors, nor eliminate its persistent infection. In this study, we illustrated that PLK1 is upregulated by KSHV, which in return suppresses KSHV lytic infection. We further demonstrated that PLK1 is a novel host target that can be inhibited pharmacologically to benefit the viral oncolysis for promotion of KSHV lytic reactivation and elimination of KSHV-positive lymphoma cells, particularly for people living with HIV (PLWH). PLK1 inhibitors also exerted the similar effect on EBV that is the other member of human gamma-herpesvirus. [ABSTRACT FROM AUTHOR]

Here, we show the fabrication of the carbon dots (CDs) with green and orange emissions from PTCDA (perylene‐3,4,9,10‐tetracarboxylic dianhydride). Using these CDs as emitters, the orange (or green) CDs LEDs were fabricated, which show electroluminescence (EL) spectra centered at 560 nm (or 498 nm) with an external quantum efficiency (EQE) of 1.98 % (1.76 %) adhering a luminescence of 626 cd m−2 (or 519 cd m−2). The machine learning was successfully used to predict PL CCT value. With the model, the white photoluminescence (PL) emission with adjustable correlated color temperature (CCT) from 3093 to 11018 K via combining blue, green, and orange CDs was achieved. Then, we obtained the warm white CDs LEDs with CCT of 3107, 4071 and 4548 K, and cold white CDs LEDs with CCT of 5632 (CIE coordinates of (0.33, 0.33), EQE: 1.18 %, luminescence: 598 cd m−2) and 6034 K accurately. [ABSTRACT FROM AUTHOR]

Here, we show the fabrication of the carbon dots (CDs) with green and orange emissions from PTCDA (perylene‐3,4,9,10‐tetracarboxylic dianhydride). Using these CDs as emitters, the orange (or green) CDs LEDs were fabricated, which show electroluminescence (EL) spectra centered at 560 nm (or 498 nm) with an external quantum efficiency (EQE) of 1.98 % (1.76 %) adhering a luminescence of 626 cd m−2 (or 519 cd m−2). The machine learning was successfully used to predict PL CCT value. With the model, the white photoluminescence (PL) emission with adjustable correlated color temperature (CCT) from 3093 to 11018 K via combining blue, green, and orange CDs was achieved. Then, we obtained the warm white CDs LEDs with CCT of 3107, 4071 and 4548 K, and cold white CDs LEDs with CCT of 5632 (CIE coordinates of (0.33, 0.33), EQE: 1.18 %, luminescence: 598 cd m−2) and 6034 K accurately. [ABSTRACT FROM AUTHOR]

Objective: Sepsis causes millions of deaths on a global scale annually. Activation of peptidylarginine deiminase (PAD) enzymes in sepsis causes citrullination of histones, which results in neutrophil extracellular trap formation and sepsis progression. This study evaluates pan-PAD inhibitor, Cl-amidine, in a model of lipopolysaccharide (LPS)-induced endotoxic shock in rabbits. We hypothesized that Cl-amidine would improve survival and attenuate kidney injury. Methods: In the survival model, rabbits were injected injected intravenously with 1 mg/kg of LPS, and then randomly assigned either to receive dimethyl sulfoxide (DMSO; 1 mcL/g) or Cl-amidine (10 mg/kg diluted in 1 mcL/g DMSO). They were then monitored for 14 days to evaluate survival. In the non-survival experiment, the same insult and treatment were administered, however; the animals were euthanized 12 hours after LPS injection for kidney harvest. Acute kidney injury (AKI) scoring was performed by a histopathologist who was blinded to the group assignment. Serial blood samples were also collected and compared. Results: Rabbits that received Cl-amidine had a higher survival (72%) compared with the rabbits that received DMSO (14%; p < 0.05). Cl-amidine-treated rabbits had lower (p < 0.05) histopathologic AKI scores, as well as plasma creatinine and blood urea nitrogen (BUN) levels 12 hours after insult. Conclusions: Pan-PAD inhibitor Cl-amidine improves survival and attenuates kidney injury in LPS-induced endotoxic shock in rabbits. [ABSTRACT FROM AUTHOR]

In this article, five different cell placement structures of a vertical inverter chain were designed in a commercial bulk FinFET technology to investigate the effect of cell placement on a single-event transient (SET) pulse. 3-D TCAD mixed-mode simulation indicated that the cell placement has a significant effect on SET pulsewidths. Heavy-ion experiments at Cyclotron in the China Institute of Modern Physics in Lanzhou also indicated that the effect of cell placement on the SET pulse is obvious. The experiment also indicated that the effect of cell placement on P-hit SET is larger than that on N-hit SET, and charge sharing in vertical was becoming as important as that in horizontal. [ABSTRACT FROM AUTHOR]

The increasing global air traffic has placed higher demands on airport pavement design. However, the behavior of rigid concrete airport pavement (RCAP) under traffic loading is very complex, and the existing reliability theory and empirical concrete pavement analysis methods cannot detect the precise RCAP failure point. Based on this background, this paper attempts to study the failure of RCAP under traffic loading from a thermodynamic perspective. It selects the Federal Aviation Administration (FAA) test in Construction Cycle 8 (CC8) phase 3 as the research material. We apply the structural stressing state theory to equate the RCAP under traffic loading to a thermodynamic system with a phase transition, i.e., we model the whole process strain data as state variables. Then, analogous to the renormalization group method of Wilson's phase transition theory to reveal the critical point of the system, this study establishes matrixes (Modes) and Hamiltonians (Characteristic parameters) that can characterize the RCAP full-process stressing state evolution under traffic loading by accumulating the difference of state variables. We attempted to verify the effectiveness of this method under such complex working conditions, which can also be applied to many other high-speed time-variant loading conditions. By applying the clustering analysis criterion, we can reveal the phase transition points of the RCAP: elastoplastic branch (EPB), failure starting (FS), and progressive failure (PF) points, respectively. Taking the NW group as an example, the variances of EPB, FS, and PF points revealed by the mode and characteristic parameter curves conducted by the two homogeneous measured point selections, respectively, are 7.7,6.4, and 6.4, which are of exceptionally high stability. We also used thermodynamic modeling to reveal the phase transition points of the remaining three RCAPs and compared the effect of different joints on the phase transition points. Finally, this study also explores the feasibility of EPB-based concrete airport pavement design. [Display omitted] • Proposing to model the stressing state of RCAP from a thermodynamic perspective. • The stressing state matrixes and Hamiltonians of the RCAP are proposed. • Applying the clustering analysis criterion revealed the phase transition points of RCAP. • Compare the EPB and FS points for different joint types of RCAP. [ABSTRACT FROM AUTHOR]

In this work, an efficient and green glycerolysis reaction catalyzed by zinc glycerolate was developed to prepare biodiesel from oleic acid. The active phase of zinc glycerolate was investigated by XRD, FTIR, 1H NMR, and 13C NMR. An interesting result was obtained that zinc glycerolate was first dissolved to form zinc oleate and then regenerated to zinc glycerolate during the reaction, which was essential for the conversion of oleic acid. The relationship between dissolved zinc glycerolate and conversion of oleic acid was determined. The regeneration of zinc glycerolate was achieved when the molar ratio of glycerol to oleic acid was higher than 0.6:1. A plausible pathway for the glycerolysis reaction catalyzed by zinc glycerolate was proposed. Zinc glycerolate could be recycled 10 times with no obvious decrease in catalytic activity, and the oleic acid conversion of 98% was achieved. In addition, zinc glycerolate was applied to catalyze glycerolysis reaction of different feedstock and demonstrated excellent performance. The results show that zinc glycerolate is a promising catalyst in glycerolysis reaction for biodiesel production. [Display omitted] [ABSTRACT FROM AUTHOR]

Attracted due to their potentially high theoretical capacities, storage redox activities, and diverse shape, cobalt phosphides (Co 2 P, CoP etc.) are thought to be the promising anodes for lithium-ion batteries (LIBs). Nevertheless, there still remain challenging bottlenecks of their low intrinsic conductivity and severe volume expansion when subjected to repeated electrochemical cycles, which unavoidably bring about structural collapse, active particle aggregation and rapid capacity degradation, and thereby poor long-term lifespan. Herein, we present a distinctively facile route and adopt metal-organic frameworks (MOFs) as the self-sacrificing hosts to construct carbon-encapsulated CoP/Co 2 P@N C composites which are composed of monodispersed electroactive Co x P (CoP/Co 2 P) nanoparticles encapsulated in carbon nanotubes (CNTs) based on N-doped carbon substrates. Remarkably, one exemplary CoP/Co 2 P@N C-600 electrode among them, when serves as anode for LIBs, exhibits high reversible capacity (977.9 mAh g−1, 100 cycles at 0.1 A g−1) and superior rate capability (639.7 mAh g−1 at 4 A g−1). Furthermore, an assembled LFP//CoP/Co 2 P@N C-600 full cell displays remarkable cycling performance. The more advantageous synergistic interaction of distinctive carbon-encapsulated architectures, robust N-doped carbon frameworks and electroactive components provides the fundamental foundation for superior lithium storage capabilities, where the synergistic interaction contributes towards enhancing electronic conductivity, offering extra electrochemical active sites, shortening the Li+/e− transport channels and alleviating volumetric variation. This contribution emphasizes the value of rationally designing MOF-derived carbon-encapsulated metal phosphide-based anodes for advanced LIBs. [ABSTRACT FROM AUTHOR]

• This review summarizes Fe-MOFs and their derivatives as electrodes and electrocatalysts. • Various synthetic strategies of Fe-MOFs and their derivatives are discussed. • The prospects and application on EECS for Fe-MOFs and their derivatives have been highlighted. • The current challenges and possible solutions are proposed. With the increasing industrial activities, the surge of population, rising global climate change concerns, as well as the increasing energy consumption and demands, traditional rechargeable batteries have started losing the capacity to meet the needs of current and future markets. In order to rise up to this challenge, the development of advanced, flexible and controllable energy technology has become the need of the hour. Development of electrochemical energy conversion and storage (EECS) technology is a potential way forward because of its high energy efficiency and environmental friendliness. One way to improve the efficiency of EECS devices is to focus on the development and improvement of their components, such as electrode materials, separators and catalysts. Recently, metal–organic frameworks (MOFs) have become an emerging class of crystalline materials in materials science and coordination chemistry due to their unique activity, interesting properties and tunable structures. Among various transition-metal based MOFs, iron (Fe)-based metal organic frameworks (Fe-MOFs) have attracted special attention due to their excellent physicochemical properties and the abundance of iron. Herein, this article reviews the recent applications of Fe-MOFs and their derivatives in electrochemical energy conversion and storage. In this review, the synthesis methods of Fe-MOFs and their derivatives, energy storage applications of Fe-MOFs in lithium-ion batteries (LIBs), sodium-ion batteries (SIBs), lithium-sulfur batteries (LSBs), supercapacitors (SCs), electrocatalysis and other batteries are discussed in detail. In addition, the achievements and challenges of Fe-MOFs and their derivatives in the fields of rechargeable batteries, supercapacitors and electrocatalysis are summarized. Furthermore, the possible innovative design principles and future prospects of Fe-MOFs and their derivatives as EECS materials are presented. [ABSTRACT FROM AUTHOR]

FinFET technology compared with planar have an increased sensitivity to single-event latch-up. TCAD simulation demonstrates that the reduction in width of MOSFET, thickness of shallow trench isolation (STI) and nMOS-to-pMOS lateral spacing will reduce the holding voltage, critical charge and increase the current gain of parasitic CMOS Silicon Controlled Rectifier (SCR). Through circuit analysis, it found that the change of parasitic vertical and horizontal resistance is mainly responsible for aforementioned phenomena. In addition, we found that the common protective measures such as guard rings spacing and epitaxial substrate become increasingly difficult. Based on the current preventive methods, we think that appropriate increasing the doping depth or the width of guard rings will improve protection from Single-Event Latch-up (SEL). Moreover, we verify the effectiveness of our methods by TCAD simulation and discuss the feasibility. • FinFET devices compared with planar is more susceptible to single-event latch-up. • For FinFET devices, the SEL prevention effect of decreasing guard ring spacing becomes weaker. • Reducing parasitic vertical resistance of guard ring can improve the effect of SEL prevention. [ABSTRACT FROM AUTHOR]

Development of Internet of Thing requires the high efficiency indoor energy harvesting solution using photovoltaic cells. This study presents the experimental investigation of the power performance of the solar harvester using crystalline silicon (c-Si) and Cu(In, Ga)Se 2 (CIGS) photovoltaic cells. Experimental studies include the optical environment setting, indoor source selection, the light source calibration and power measurements. The measured efficiencies of c-Si and CIGS cells are in the range of 1.5%–7.4% with strong source-dependency. Efficiencies of power conversion module varies in the range of 65%–75%. Furthermore, the efficiencies of solar cells and modules vary with the change of level of illuminance. Correction factors of cell efficiency and module efficiency are derived from experimental data. In general, c-Si and CIGS cells showed acceptable performance under wideband light source. However, their power outputs are limited under the various narrowband indoor light sources. Future development of the indoor-used photovoltaic cells may focus on the narrowband indoor light applications. • Both c-Si and CIGS cells showed limited performance for narrowband sources. • Indoor cell efficiencies are between 1.5 and 7.4% that are lower than outdoor values. • Power conversion efficiency of harvester is within 65%–75% under indoor sources. • Power of 15.6 cm by 15.6 cm cell c-Si harvester is ranged from 1.0 mW to 75.0 mW. • New cell technologies are required for high power output of narrowband sources. [ABSTRACT FROM AUTHOR]

The dynamic response of the coiled tubing (CT)-in-riser system is critical to the success of offshore CT operations. The purpose of this work is to investigate the mechanical behavior of the CT and the riser and analyze the influencing factors of the coupled system. This paper builds dynamic models of the micro elements of the CT and the riser, and then a coupled model of the CT-in-riser system is presented considering the excitation of ocean loads and the coupling interaction between the inner pipe and the outer pipe. The dynamic coupled model is solved by the finite element method. A finite element model of the CT-in-riser system is built using the Abaqus/AQUA module. The effect of the operating parameters including the top injection force, the top tension, the platform offset, the annular clearance, and the friction coefficient, and the environmental parameters including the ocean depth, current speed, wave period, and wave height are discussed. The results show that the top tension should be properly controlled; the platform offset and friction coefficients should be reduced; the annular clearance should be appropriately reduced; a low current speed and wave height should be selected for operation; and the wave period and wave height have a little effect on the CT axial force. This research can provide important theoretical support for the offshore CT application. • A coupled model of the CT-in-riser system is presented. • A finite element model of CT-in-riser system using the Abaqus/AQUA module is built to solve the dynamic coupled model. • The effects of the operating parameters and the environmental parameters are discussed. [ABSTRACT FROM AUTHOR]

Dam is an important part of the national infrastructure, and its safety has been widely concerned. Risk identification of dams plays a significant role in risk assessment and control. Finding out some critical failure paths through adopting timely measures can help reduce the risk occurrence probability effectively. This paper develops an identification method based on the credibility and the interval analytic hierarchy process (IAHP) methods, namely, consistency and difference-based interval analytic hierarchy process (CDB-IAHP) method, to identify the critical failure paths of dams exactly considering the dynamic cognition degree of decision-makers. Based on the fault tree analysis (FTA) method, the framework and analysis for critical failure paths identification of a gravity dam and an Earth-rockfill dam are conducted and made. The results show that the critical failure paths obtained by the proposed method are in line with the statistical data, and the importance of disaster causing factors has some difference with the traditional method. Additionally, some engineering and nonengineering measures are suggested to reduce the impact of potential failure paths. The applications demonstrate that the proposed method shows good applicability for risk analysis and critical failure path mining of dams. [ABSTRACT FROM AUTHOR]

• A novel and sustainable inhibitor was extracted from maize gluten meal. • The extracts possess amide structure and exhibit a mix-type inhibitor. • Surface analysis provides the evidence for extract adsorbed layer on steel. • Green extract is an effectively inhibitor for reinforced steel in concrete. The corrosion inhibitive effect of maize gluten meal extracts for steel in simulated concrete pore solution with 3.0 wt% sodium chloride was investigated. The results acquired from EIS and polarization studies were in a good agreement, which suggest an increase in the corrosion resistance of steel with the extract introduced comparatively to the blank systems. Adsorption of extracts onto the steel surface obeyed the isothermal Langmuir adsorption, was mainly controlled by physisorption. The confirmatory evidence of enhanced corrosion resistance during adsorption was obtained from the SEM-EDS, ATR-FTIR and surface structure analysis. Furthermore, the amide bond structures of the main constituents in extract were also beneficial to adhere to steel surface. The sustainable extract of maize gluten meal is a by product of starch industry, which is an effectively and promisingly inhibitor for reinforced steel with the anticorrosion efficiency of 62.71–88.10%. [ABSTRACT FROM AUTHOR]

Frequency response analysis (FRA) is a widely used approach for detecting winding faults in a transformer. Appropriate and quantitative FRA features will help to improve the accuracy of fault diagnosis. In this study, a novel FRA interpretation including new image features is proposed based on the image processing technique. First, winding faults of different windings are simulated in a test autotransformer and the FRA curves are measured under various faults. Then frequency region division method and image processing technique are first applied to the measured FRA curves. The area ratio and centroid deviation in different frequency regions are calculated through a novel algorithm. Finally, the image features are used as the inputs to support vector machine model. Additionally, three different parametric optimisation algorithm are compared during the training process. The results show that the particle swarm optimisation and image feature exhibit best performance for identifying winding faults. [ABSTRACT FROM AUTHOR]

A novel fluorescent probe CN3, containing 1,8‐naphthalimide and picolinate units, was synthesized, and its structure was characterized by 1H nuclear magnetic resonance spectroscopy (H NMR), 13C nuclear magnetic resonance spectroscopy (C NMR), and mass spectroscopy techniques. The detection property of CN3 toward copper ions (Cu2+) has been investigated in ethanol–HEPES buffer (v/v = 1/1, pH = 7.40) solution by UV–Vis absorption and fluorescence emission spectra. The results showed that CN3 had a highly selective and sensitive fluorescence quenching response to Cu2+, which was attributed to the generation of weak fluorescent N‐ethyl‐4‐hydroxyphenyl‐1,8‐ naphthalimide (compound 2) in polar ethanol–HEPES buffer (v/v = 1/1, pH = 7.40) via selective hydrolysis reaction. The detection of CN3 for Cu2+ was not influenced in the presence of other competing metal ions, and the limit of detection was as low as 50.0 nM. Therefore, the color of CN3 changed from colorless to yellowish when the Cu2+ was added. Furthermore, the fluorescent probe CN3 was utilized to detect Cu2+ in real water samples with fine performance. [ABSTRACT FROM AUTHOR]

A novel coumarin derivative CTT was synthesized via the condensation of 7‐(N,N‐diethylamino) coumarin‐3‐aldehyde with 5‐amino‐1,3,4‐thiadiazole‐2‐thiol and its structure was characterized using infrared spectroscopy (IR), 1H NMR, mass spectrometry (MS) techniques, and elemental analysis. The recognition properties of CTT with metal ions were investigated in CH3CN–H2O (v/v = 1/1) solution using UV–vis absorption and fluorescence emission spectrum method. The results showed that CTT could monitor Cu2+ and Hg2+ simultaneously as a dual‐function chemosensor in CH3CN–H2O (v/v = 1/1). CTT could be used to detect Cu2+ colorimetrically; when using CTT, a color change from yellowish‐brown to yellowish‐green could be readily observed by the naked eye. CTT showed turn‐on fluorescent recognition of Hg2+, the fluorescence enhancement was attributed to the inhibited C=N isomerization and the obstructed excited state intramolecular proton transfer (ESIPT) of CTT. The recognition mechanism of CTT for Cu2+ and Hg2+ was studied by experiments and theoretical calculations, respectively. Therefore, CTT has the ability to be a "single chemosensor for dual targets." [ABSTRACT FROM AUTHOR]

• Power degradation is caused by grain boundary cracking and interface delamination. • Tensile and shear stress affects the cell microstructure and stacking integrity. • Strain (<1.5%), power degradation is controlled by CIGS grain boundary cracking. • Strain (>2.0%), power degradation is governed by delamination of CIGS-Mo interface. • Modified power output formula is proposed to take account strain-induced degradation. In this work, strain dependent effect on power degradation of thin film Cu(In.Ga)Se 2 (CIGS) solar cell is studied though experimental methods. Strain leads to grain boundary cracking of CIGS absorption layer and delamination of CIGS-Mo interface. Experimental methods include the tensile testing, X-ray diffraction (XRD), scanning electron microscope (SEM). Multi-linear responses with negative coefficients between strain and short-circuit current and open-circuit voltage are observed. The first linear region is caused by the grain boundary cracking of CIGS layer. The second linear region is caused by the delamination at CIGS-Mo interface. Correction formula of the cell maximum power output due to applied strain is derived from slope coefficients. The connections between stress (tensile and shear) and failure modes (boundary cracking and delamination) of CIGS thin film cell are discussed. [ABSTRACT FROM AUTHOR]

The windings of a traction transformer are always be threatened by the fluctuation of the load. Frequency response analysis (FRA) is regarded as the most effective method to diagnose the winding deformation. Appropriate FRA modelling method may help to predict typical winding faults for large transformers. The existing model usually simplify dozens of winding disks into several disks, it is applicable when analysing small displacement. However, when the disks between windings are seriously misplaced, the conventional model may not be suitable. This study presents an improved lumped parameter circuit model considering intersection capacitances and mutual inductance between windings. The feasibility of the proposed model is verified based on a 10 kV test transformer. Finally, the model is applied for a 220 kV traction transformer, the variation of parameters and features are analysed for axial displacement of different windings. The results show that the axial displacement may lead to increase of resonance frequency and decrease of amplitude. The low‐frequency band (1–30 kHz) may be regarded as visible features for diagnosing axial displacement of H winding and the middle frequency band (50–200 kHz) may be a characteristic band for diagnosing axial displacement of T winding. [ABSTRACT FROM AUTHOR]

In order to reduce the potential toxicity to the environment after treatment of radioactive waste water, an eco-friendly graphene oxide nanoribbons/chitosan (GONRs-CTS) composite was prepared and utilized for adsorption of Th(IV) from aqueous solution. The GONRs-CTS adsorbent was characterized by XRD, FTIR and SEM, indicating that GONRs-CTS contains a large amount of oxygen-containing groups and chitosan was successfully attached to the GONRs surface. The Th(IV) adsorption on GONRs-CTS was endothermic and spontaneous, with the maximum single layer adsorption capacity was 140.6 mg g−1 at pH = 3.0, in the contact time of 12 h. The adsorption process was consistent with pseudo-second-order kinetics and the Langmuir isotherm model. [ABSTRACT FROM AUTHOR]

We synthesized TiO 2 nanotubes (TNTs) from TiO 2 gel by hydrothermal method. Then the TiO 2 nanotubes were modified by Ag nanoparticles (Ag-TNTs) by in-situ photodeposition reaction. In this work, we reported the photovoltaic performance of Ag-TNTs composites photoanode in dye-sensitized solar cells. The two layers photoanode consisted of TiO 2 nanoparticles (P25) and Ag modified TiO 2 nanotubes (Ag-TNTs) was fabricated by doctor blade method. UV–vis, Electrochemical impedance spectroscopy (EIS) measurements were performed to investigate the electro-hole recombination and transport processes. The Ag nanoparticles photodeposited on TNTs surface can improve the cell performance by enhancing the light absorption and promoting the electron-hole separation and transfer. The P25/Ag-TNTs-8H configuration photoanode has the best photoelectric conversion efficiency with the filling factor (FF) reached 53.63% and the efficiency(η) reached 7.2%. Image 1 • One-dimensional TiO 2 nanotubes were synthesized by hydrothermal method using TiO 2 gel as precursor. • Photodeposited Ag nanoparticles modfied TiO 2 nanotubes (Ag-TNTs) were applied to fabricate DSSCs photoanode. • The Ag nanoparticles photodeposited on TNTs surface can effectively improve the DSSCs device performance. [ABSTRACT FROM AUTHOR]

Comorbid cognitive and behavioral deficits are often observed in patients with epilepsy. It is not clear whether the brain networks of patients with epilepsy without cognitive decline differs from that of healthy controls in different frequency bands in the task-state. The purpose of our study was to explore whether epilepsy affects the structure of brain networks associated with cognitive processing, even when patients with epilepsy do not have cognitive impairment. We designed an audiovisual discrimination task and recorded electroencephalogram (EEG) data from healthy controls and patients with epilepsy. We established constructed time-varying brain networks across the delta, theta, alpha, and beta bands on the task-state EEG data during audiovisual integration processing. The results showed changes in the structure of the brain networks in the theta, alpha, and beta bands in patients with epilepsy who had no cognitive deficit. No significant difference in the connectivity strength, clustering coefficient, characteristic path length, or global efficiency was noted between patients and healthy controls. Moreover, the structure of brain networks in patients showed no correlation with the behavioral performance. The repeated abnormal firing of neurons in the brain of patients with epilepsy may inhibit it from optimizing networks into more efficient structures. Epilepsy might affect decision-making ability by damaging the neural activity in the beta band and preventing its correlation with decision-making behaviors. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synergistic effect of Zr and Hf alloying on cross fluvial microstructure of CoCrFeNi eutectic high-entropy alloys. • Element alloying induce a brawny river eutectic structure. • The correlation between precipitation strengthening and solid solution strengthening are discussed. In this study, selective vacuum arc furnace is used to fabricate CoCrFeNi-M 0.4 (M = Zr, Hf, 50 %Zr + 50 %Hf) EHEAs, and the content of Zr and Hf element is controlled to solve the balance of strength and plasticity in HEAs. Through alloying with Zr or Hf, the cross fluvial eutectic structure of CoCrFeNiZr 0.4 and CoCrFeNiHf 0.4 are consists of FCC-CoCrFeNi matrix phase and intermetallic. CoCrFeNiZr 0.2 Hf 0.2 EHEAs, which is synergistic alloying with Zr and Hf, have a brawny river eutectic structure of both soft FCC and hard Ni 7 Hf 2 intermetallic. The synergistic precipitation strengthening and solid solution strengthening result in the fracture strength and ductility of CoCrFeNiZr 0.2 Hf 0.2 reaching 3475.7 MPa and 14.1 %, respectively. Furthermore, CoCrFeNiZr 0.2 Hf 0.2 exhibit a good combination of strength and plasticity through synergistic alloying effect compared with other CoCrFeNi HEAs. [ABSTRACT FROM AUTHOR]

Accurate 3D representations of multiphase layered composite fabric, including distinguish and label the pores, matrices, warp and weft yarns, can assist in understanding and ultimately improving composite material design performance. In this work, a new data enhancement algorithm is proposed to generate realistic-looking artificial learning datasets for expanding the datasets. Then, we demonstrate how supervised, the Swin Transformer approach can help to realize accurate segmentation of low-resolution and poor-contrast fabric datasets by populating databases with real and artificial learning datasets. Most of the pixels were correctly identified and the boundaries of the yarn could be identified clearly, except for some spots and a few merged boundaries. The work presented here provides an effective tool that can be widely used in semantic segmentation for various composite materials (woven composites, fiber-reinforced composites, short-fiber materials, etc.), which enables higher-precision reconstruction of fiber-composites and significant reduction in dataset processing time, and provides a route to generating artificial learning dataset. [ABSTRACT FROM AUTHOR]

• ZnMn 2 O 4 microspheres/GCE displayed high electrocatalytic activity towards H 2 O 2 reduction. • The non-enzymatic sensor exhibited wide linear range of 0.02 ˜ 15 mM with high sensitivity of 277.1 mA mM−1 cm−2. • The proposed H 2 O 2 sensor showed excellent anti-interference ability and stability. With a facile solvothermal technique, ZnMn 2 O 4 microspheres were synthesized in this work, which were used as enzyme mimics for the electrocatalytic reduction of H 2 O 2. The morphology, crystal phase and structure of the ZnMn 2 O 4 microspheres underwent characterization under X-ray diffraction spectroscopy, Raman spectroscopy, energy-dispersive spectroscopy, and scanning electron microscopy. The synthesized ZnMn 2 O 4 microspheres showed an average diameter of 2 μm with great crystallinity, and exhibited excellent catalytical activity towards H 2 O 2 electroreduction in alkaline media. The glassy carbon electrode modified by ZnMn 2 O 4 microspheres showed a linear amperometric response for H 2 O 2 in a wide concentration range of 0.02 ˜ 15 mM with detection limit of 0.13 μM under the optimized conditions. Besides, the sensor proposed here was successfully used to determine H 2 O 2 in milk, suggesting that ZnMn 2 O 4 microspheres can be used for non-enzymatic electrochemical sensor applications. [ABSTRACT FROM AUTHOR]

Desulfurization is important to the enhancement of biodiesel quality. In this study, the effects of reactant and catalyst addition and operations conducted on sulfur content at each stage during the biodiesel preparation process were examined. Based on the results of sulfide qualification and quantification, a high vacuum distillation method was developed to remove the sulfides in crude biodiesel. Biodiesel was separated into different fractions based on the boiling point and the sulfur content of each fraction was determined. Experimental results showed that most sulfides were distilled out with light and heavy fractions. Intermediate fraction was separated from the other fractions, resulting in high quality biodiesel with low sulfur content. The total yield of distillation fractions with sulfur content lower than 10 ppm reached 84.1%. A set of distillation facility with capacity of 10 m3/h was designed and developed accordingly for large-scale tests. The yield of low-sulfur biodiesel was around 83%, close to that obtained in the laboratory studies. In addition, economic analysis showed that the distillation facility can make revenue of more than $1.8 million per year, indicating that high vacuum distillation is economically feasible and promising for biodiesel desulfurization, especially in industrial application. Image 104946 • A high vacuum distillation method was proposed to remove sulfides in crude biodiesel. • Sulfides in crude biodiesel were qualitatively and quantitatively analyzed. • The total yield of biodiesel with sulfur content lower than 10 ppm was 84.1%. • Distillation facility with capacity of 10 m3/h was developed for large-scale tests. • The process is economically feasible for low-sulfur biodiesel production. [ABSTRACT FROM AUTHOR]

SiO x is proposed as one of the most promising high-performance anodes for its favorable capacity and stable lithium insertion/extraction electric potential, however its effective commercial application still faces giant challenge. To overcome poor electrical conductivity and huge volume effect of silicon oxide-based material, we adopt a valid strategy to synthesis the SiO x nanosphere double-wrapped by MoS 2 and multi-walled carbon nanotubes (CNTs) as anode material. The influences of MoS 2 and CNTs on the structure, morphology and electrochemical performances of nanohybrid are probed detailly by transmission electron microscopy, X-ray photoelectron spectroscopy and charge-discharge measurements. The results show that as-prepared nanohybrids release a steady reversible capacity of 798 mAh g−1 with high capacity retention of 81.4% at 500 mA g−1 after 300 cycles. The outstanding electrochemical properties can be ascribed to the facts that the hollow mesoporous structure affords ample buffer space and the introduction of MoS 2 with a two-dimensional layered structure can provide more exposed active-sites for lithium adsorption, as well as the CNTs wrapping can form a favorable conductivity matrix, endowing the nanocomposites with great structural stability. Accordingly, this new structure design by means of a heterogeneous dual-wrapped architecture develops a significant strategy for the development of high-performance SiO x -based anode materials. Unlabelled Image • Heterogeneous dual-wrapped architecture of SiO x /MoS 2 -CNTs is successfully prepared. • The hollow structure shortens the transportation of Li+/e− and offers buffer space. • Wrapping MoS 2 can own more exposed active sites for promoting transport of Li+/e−. • The conductive twining CNTs form a favorable conductivity framework. • The material presents excellent cycling performance and rate capability. [ABSTRACT FROM AUTHOR]

The creation of a catalytic method that possesses high activity and effective reusability for the oxidative cleavage of vegetable oils and their derivatives to prepare bio-based oxo-chemicals is a challenge. This work introduces a “release and capture” catalytic system consisting of H2O2, WO3 and mesoporous SnO2. This system was intended to promote catalyst reusability in the oxidative cleavage of methyl 9,10-epoxystearate (ME) to the corresponding aldehydes. No organic solvent was used in the reaction. The reaction temperature, molar ratio of ME/WO3/H2O2, and reaction time were optimized to 70 °C, 1/0.017/1.3, and 20 min, respectively. Under these conditions, complete ME conversion and 80% aldehyde yield were obtained. The hot filtration experiment and ICP-MS analysis confirmed the leaching of tungsten. Mesoporous SnO2 did not affect the ME conversion and aldehyde yield, but effectively adsorbed the leached tungsten. The catalyst in this system showed no significant decrease in activity after being reused ten times. [ABSTRACT FROM AUTHOR]

Highlights • The measurement of density, viscosity and vapor pressure for three typical fatty acid 2-ethylhexyl esters were carried out. • Correlation of the density and viscosity of fatty acid 2-ethylhexyl esters using empirical temperature dependent equations. • The experimental vapor pressures were well correlated with the Antoine and Wager equations. • The Clausius-Clapeyron equation was used to calculate the molar evaporation enthalpy. Abstract Fatty acid 2-ethylhexyl esters are used for the eco-friendly production of biolubricant. There are several reports on their synthesis, but thermodynamics and transport data of these compounds are lacking. Herein, density and viscosity of palmitic acid 2-ethylhexyl ester, stearic acid 2-ethylhexyl ester and soya oil 2-ethylhexyl esters in the temperature range of T = (298.18–368.15) K at atmospheric pressure were measured and the vapor pressure in the temperature range of T = (476.95–500.85, 477.05–498.05, 477.75–500.05) K was determined. The obtained experimental data were correlated using temperature-dependence correlation equations, and the correlation coefficients of all the equations were over 0.999. In order to examine the reliability of the data, the GCVOL group method was used to evaluate densities for these fatty acid 2-ethylhexyl esters with the maximum relative deviation of −1.34%. The experimental viscosity data of synthesized 2-ethylhexyl esters were compared with those of lauric acid 2-ethylhexyl ester, palmitic acid n-octyl ester and oleic acid 2-ethylhexyl ester from previous studies. In addition, the molar enthalpy of vaporization at the mean temperature of the experimental range was calculated for the first time using the Clausius-Clapeyron equation. [ABSTRACT FROM AUTHOR]

The hollow Si nanospheres modified by the mechanically robust titanium dioxide (TiO 2 ) shell and the uniform carbon layer are intentionally designed and successfully prepared as the anode active material of high performance lithium-ion batteries. The effects of the robust TiO 2 shell and the uniform carbon layer on the structure and electrochemical performances for the Si@TiO 2 @C nanospheres are studied in detail by X-ray photoelectron spectroscopy, transmission electron microscopy, X-ray diffraction and charge/discharge tests. The results show that the hollow structure of the Si core can spontaneously absorb the huge volume expansion stress, the robust TiO 2 shell is used as a compact fence to promote the expansion towards the interior of the Si cavity instead of the exterior in the processes of charge/discharge, and the uniform carbon layer can effectively enhance the electrical conductivity and further control the integrity and stability of the well-wrapped core-shell-shell framework. Typically, the resultant hollow Si@TiO 2 @C nanospheres exhibit a high initial discharge capacity of 2557.1 mAh g −1 with coulombic efficiency of 86.06% as well as a large recuperative discharge capacity of 1270.3 mAh g −1 after 250 cycles at 1 A g −1 with a mean coulombic efficiency of 99.53%. Therefore, the hollow Si@TiO 2 @C nanospheres prepared by one-step sol-gel coating process show outstanding electrochemical properties and are considered as a prospective candidate to the adhibitions of the anode material for new generation power LIBs. [ABSTRACT FROM AUTHOR]

Abstract The hollow mesoporous silicon nanobox dually encapsulated by tin oxide and carbon layers is successfully fabricated and used for anode active material of lithium ion battery. The effects of the double coating layers on the structure, morphology and features of nanocomposite are systematically investigated by transmission electron microscopy, field emission scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and galvanostatic charge-discharge tests. The results reveal that hollow mesoporous silicon/tin oxide/carbon nanobox has the adjustable void space and a rationally designed hierarchical structure, which permits the free expansion of Si core without breaking double coating layers and preserves the structural integrity of the electrode during the (de)lithiation processes, as well as significantly enhances the electronic conductivity of anode. As expected, the resultant hollow mesoporous silicon/tin oxide/carbon nanobox exhibits a high reversible capacity up to 1535 mAh g−1 at 0.5 A g−1 after 200 cycles of (dis)charging due to the unique nanostructure. Especially, the as-synthesized nanocomposite exhibits an excellent rate capacity as high as 858 mAh g−1 at 6 A g−1. This rational structure design and innovative approach can be of visible significance for the development of new anode active materials of next-generation lithium-ion battery. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Vehicle networks is a promising technique, which could provide ubiquitous wireless access for vehicles and realize intelligent transportation. Motivated by the recent advances on device-free wireless sensing, this paper explores a novel technique, which could estimate the speed of a vehicle by analyzing its influence on surrounding wireless signals from roadside wireless infrastructures, such as WiFi. This technique could enable vehicle networks with new moving speed sensing ability and evolve it into a large-scale sensing network, which could monitor the traffic status seamlessly. To achieve this goal, in this paper, we propose and formulate a model to characterize the relationship between the phase and amplitude measurements and the vehicle speed. Based on the model, we develop an efficient method to detect the vehicle and estimate its speed accordingly using the frequency-domain information involved in the spectrogram. We carry out extensive experiments utilizing commodity WiFi. The experimental results reveal that the proposed method could estimate the speed with an error of less than 2.6 km/h, which meets the United Nations regulation for speedometer. [ABSTRACT FROM AUTHOR]

• Hybridization of glass fiber into carbon composite presents toughening effect. • Infrared thermography accurately evaluates the progressive damage. • Off-axial tensile properties are more sensitive than on-axial for hybrid composites. • The quick crack propagation in hybrid composites is prevented. • Damage of interior carbon fiber layers can be restrained through hybridization. Hybrid composites are increasingly attractive for advanced engineering applications. In this study, the open-hole tensile (OHT) properties and failure mechanism of plain woven carbon fiber, glass fiber, and carbon/glass hybrid fiber composites under on-axis (0°) and off-axis (45°) loads were investigated through experimental and numerical approaches. The progressive damage was characterized by high-speed infrared thermography. The numerical simulation presented a good explanation on the damage development. It indicates that the carbon/glass hybrid composites exhibited significant improvement in failure strain and toughness compared to pure carbon fiber composite. With the insertion of glass fiber layers, the failure modes of hybrid structures were modified and quick propagation of cracks was prevented. Once the cracking on their carbon layers had initiated there was an increase in damage to glass fiber layers showing the transfer of stress from carbon layers to glass layers. Similar mechanical properties were reached among sandwich-like hybrid samples in on-axis tension, but much greater properties can be achieved when the carbon fiber at the interior layers of the hybrid specimens under off-axis load. Since glass fiber with great ductility was laminated as the surface layers in hybridization, resulting in less delamination and higher ultimate strength in 45○ off-axis tension. [Display omitted] [ABSTRACT FROM AUTHOR]