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Continuous capacity increase in electrochemical cycling, termed as electrochemical activation, is a frequently observed but rarely systematically studied phenomenon. Such phenomenon is noted in a preliminary study of carbon cathode for dual ion battery, showing gradual discharge capacity growth from 186 mAh g−1 (the 1st) to 320 mAh g−1 (the 300th). Systematical characterizations are carried out to investigate this phenomenon occurred on the carbon cathode, hydrothermally reduced graphene oxide (HrGO). The electrochemical activation comes from surface area increment, originated from multilayer reduced graphene oxide rolls formation and accumulation and structural order increase in cycling. The formation of rolls is plausibly a result of strain release of reduced graphene layers after electrochemical interaction with PF6−. Additionally, charge storage mechanism of HrGO is revealed. At active surface sites of HrGO, PF6− is consistently stored in a pseudocapacitive manner. In contrast, at well-crystallized domains, pseudocapacitive PF6− uptake occurs at low voltage region while PF6− intercalation dominates at higher potentials. Supportive lithium storage also contributes to total capacity. Comprehensively, this work offers valuable insights of electrochemical activation and carbon cathodes’ electrochemical behaviors and will facilitate the construction of high-capacity carbon cathodes.

As the demand for education continues to increase, the relative lack of physical resources has become a bottleneck hindering the development of school physical education to a certain extent. This research mainly discusses the evaluation index system of school sports resources based on artificial intelligence and edge computing. Human resources, financial resources, and material resources in school sports resources are the three major resources in resource science. University sports stadium information publicity uses Internet technology to establish a sports information management platform and mobile Internet terminals to optimize university sports resources and stadium information management services. It uses artificial intelligence technology to improve venue information management. It establishes a comprehensive platform for venue management information, collects multidimensional information, provides information resources and accurate information push, and links venue information with public fitness needs. Using edge computing to realize nearby cloud processing of video data, reduce the phenomenon of black screen jams during live broadcast, improve data computing capabilities, and reduce users’ dependence on the performance of terminal devices, build a smart sports resource platform, combine artificial intelligence (AI) to create smart communities, smart venues, and realize intelligent operations such as event service operations and safety prevention and control in important event venues. During the live broadcast of the student sports league, the nearby cloud processing of video data is realized in the form of edge computing, which improves the data computing ability and reduces the performance dependence on the user terminal equipment itself. In the academic survey of college physical education teachers, undergraduates accounted for 26.99%, masters accounted for 60.3%, and doctoral degrees accounted for 12.8%. This research will help the reasonable allocation of school sports resources.

Targeting for flexible, broadband ultrasound sensors, a new breed of nanographene platelet (NGP)/polyimide (PI) film is inkjet printed with morphologically optimized NGP/poly (amic acid) hybrid-based nanocomposite ink. The ink is produced with high-shear liquid phase exfoliation from inexpensive bulk graphite, manifesting good printability and high graphene concentration as high as 13.1 mg mL−1. Featuring an ultra-thin thickness (∼1 μm only), the inkjet-printed NGP/PI film sensor is demonstrated to possess excellent thermal stability and high adhesive strength reaching the American Society for Testing and Materials 5B level. The highly uniform and consolidated NGP/PI nanostructure in the sensor enables the formation of π-π interaction between NGPs and PI polymer matrix, and the quantum tunneling effect is triggered among NGPs when ultrasound traverses the sensor. This sensing mechanism endows the NGP/PI sensor with good sensitivity, fidelity and accuracy, showing comparable performance as prevailing commercial ultrasound sensors such as piezoelectric sensors. The film sensor has a proven gauge factor as high as 739, when sensing ultrasound at 175 kHz, and an ultrabroad responsive spectrum up to 1.6 MHz.

Nanostructured transition-metal oxides have been under intensive investigation for their tantalizing potential as anodes of next-generation lithium-ion batteries (LIBs). However, the exact mechanism for nanostructures to influence the LIB performance remains largely elusive. In this work, we discover the nanostructure-mediated lithiation mechanism in Co3O4 anodes using ex situ transmission electron microscopy (TEM) and X-ray diffractometry: while Co3O4 nanosheets exhibit a typical two-step conversion reaction (from Co3O4 to CoO and then to Co0), Co3O4 nanoarrays can go through a direct conversion from Co3O4 to Co0 at a high discharge rate. Such nanostructure-dependent lithiation can be rationalized by the slow lithiation kinetics intrinsic to Co3O4 nanoarrays, which at a high discharge rate may cause local accumulation of lithium to initiate a one-step Co3O4-to-Co0 conversion. Combined with the larger volume change observed in Co3O4 nanoarrays, the slow lithiation kinetics can lead to inhomogeneous expansion with large stress developed at the reaction front, which can eventually cause structure failure and irreversible capacity loss, as explicitly observed by in situ TEM as well as galvanostatic discharge-charge measurement. Our observation resolves the nanostructure-dependent lithiation mechanism of Co3O4 and provides important insights into the interplay among lithiation kinetics, phase evolution, and lithium-storage performance, which can be translated into electrode design strategies for next-generation LIBs.

The commercialization of TiO2 materials for lithium-ion battery (LIB) anodes has been seriously limited due to unsatisfactory capacities and high voltage plateaus vs. Li/Li+ (∼1.75 V). In this work, we synthesized unique dual-phase TiO2 nanowires composed of anatase and TiO2–B phases with tunable phase ratios and studied their electrochemical performance in the extended potential range of 0.01–3.0 V. It was found that the dual-phase nanowire with a phase ratio of ∼1.0, named TiO2-350, possesses the best rate and cyclic performance. More importantly, lowering the discharge cut-off voltage from 1.0 V to 0.01 V significantly increases the capacities, and moreover results in a decreased average discharge voltage of ∼0.58 V vs. Li/Li+. At the rates of 0.5C and 1C, TiO2-350 delivers the ultrahigh capacities of 518.0 and 444.5 mA h g−1 and remarkable long-term cyclic stability, which are strikingly higher than those reported in the literature and the theoretical capacity of TiO2. Cyclic voltammetry results indicated that the ultrahigh capacity of the TiO2 nanowire is the main reason that the capacitive contribution is below 1.0 V. Structural analyses indicated the solid solution reaction of TiO2-350 nanowires with Li+ and the excellent structure stability during cycling, which contributes to the excellent cyclic performance of nanowires. Furthermore, the TiO2-350 anode exhibits superb low-temperature performance between 0.01 V and 3.0 V at 273 K and 248 K. This work demonstrates a TiO2-based anode with ultrahigh capacity and low working potential, and will promote the practical application of TiO2-based materials for all-climate LIB anodes.

Seasonal and spatial distributions of dissolved and particulate dimethylsulfoxide (DMSOd, DMSOp) were measured in the East China Sea and the Yellow Sea during March–April 2011 and October–November 2011. The concentrations of DMSOd and DMSOp in the surface water were 20.6 (5.13–73.8) and 8.90 (3.75–29.6) nmol/L in spring, and 13.4 (4.17–42.7) and 8.18 (3.44–22.6) nmol/L in autumn, respectively. Both DMSOd and DMSOp concentrations revealed similar seasonal changes with higher values occurring in spring, mainly because of the higher phytoplankton biomass observed in spring. Moreover, the ratios of DMSOp/chlorophyll a also exhibited an apparent seasonal change with higher values in autumn (35.7 mmol/g) and lower values in spring (23.4 mmol/g), thereby corresponding with the seasonal variation in the proportion of DMSO producers in the phytoplankton community between spring and autumn. In addition, DMSOd and DMSOp concentrations in the surface seawater revealed obvious diurnal variations with the maxima appearing in the afternoon.

Rechargeable lithium-sulfur batteries have been regarded as the promising next generation energy storage system due to their overwhelming advantages in energy density. However, their practical implementations are hindered by severe capacity fading and low sulfur utilization, which are caused by polysulfide shuttling and the insulating nature of sulfur. Herein, sulfur-embedded porous multichannel carbon nanofibers coated with MnO2 nanosheets (CNFs@S/MnO2) are rationally designed and fabricated as cathode for lithium-sulfur battery. The high conductivity of porous multichannel carbon nanofibers facilitates the kinetics of electron and ion transport in the electrodes, and the porous structure encapsulates and sequesters sulfur in its interior void space to physically retard the dissolution of high-order polysulfides. Moreover, the MnO2 shell exhibits a combination of physical and chemical adsorption for high-order polysulfides, which could sequester polysulfides leaked from the carbon matrix after long-time charge/discharge cycles, resulting in enhanced cyclic stability. As a result, the electrode delivers a specific capacity of 1286 mA h g−1 at 0.1 C and 728 mA h g−1 at 3 C. And the capacity could remain 774 mA h g−1 after 600 cycles at 1 C.

Due to the relatively small surface area of carbon cloth and its low possibilities for further architecturing, various hierarchical structures are in situ grown on carbon cloth in the fabrication of high sulfur loading cathode to achieve outstanding electrochemical properties. Despite high specific capacities in previously reported cathodes, areal capacity is unsatisfactory due to loading of low-mass sulfur. New techniques are still demanding to fulfill simultaneous achievements of high sulfur loading and high areal capacity. Herein, a three-dimensional interconnected network composed of Co3O4 nanosheets is constructed for the first time on carbon cloth for high sulfur loading. In terms of this three-dimensional interconnected network, Co3O4 nanosheets are not only grown on carbon fiber surfaces which can significantly increase the surface area for sulfur anchorage compared to pristine carbon cloth, but also within inter-fiber spacing where two adjacent carbon fibers are bridged, which is not yet achieved in any previously reported hierarchical structures of carbon cloth-based sulfur cathodes. Thus, this functionalized carbon cloth can provide significantly enlarged spaces for distribution of high mass loading sulfur. The thus-obtained sandwich-type sulfur cathode that integrates the functionalized carbon cloth and a pristine carbon cloth interlayer delivers a high areal capacity of ∼3.63 mA h cm−2 at a sulfur mass loading of ∼5.5 mg cm−2 and a capacity retention rate of ∼93% after 200 discharge/charge cycles, which demonstrates a superior areal capacity to most of the previously reported carbon cloth-based sulfur cathodes. This study presents a new strategy for constructing a three-dimensional interconnected network to achieve high mass loading of active materials on flexible supports.

Malaria remains a global health problem. The relationship between Plasmodium spp. and the gut microbiota as well as the impact of Plasmodium spp. on the gut microbiota in vertebrate hosts is unclear. The aim of the current study was to evaluate the effect of blood-stage Plasmodium parasites on the gut microbiota of mice. The gut microbiota was analyzed by 16S rRNA sequencing and bioinformatic analyses at three stages. The gut microbiota changed during the three phases: the healthy stage, the infection stage, and the cure stage (on the 9th day after malarial elimination). Moreover, the gut microbiota of these infected animals did not recover after malaria infection. There were 254 operational taxonomic units (OTUs) across all three stages, and there were unique strains or OTUs at each stage of the experiment. The percentages of community abundance of 8 OTUs changed significantly (P

A nanocomposite-based sensor ink made from carbon black and polyvinyl pyrrolidone was developed for fabricating a new breed of sensor by an inkjet printing approach, to accommodate the general purposes of structural health monitoring. This ink can be directly deposited onto the surface of various substrates or engineering structures such as polyimide film via computer-aided design to configure nanocomposite sensor arrays or dense sensor networks. Strong structure adaptability and high flexibility make this sensor a promising candidate to alternate traditional piezoresistive and piezoelectric sensors, in signal acquisition of dynamic disturbance on complex engineering structures. Lightweight and without the need to use wires or cables, the printed sensor network significantly reduces the weight and volume penalty imposed on the host structures, even when the network is deployed at a large scale. It also minimizes the possibility of exfoliation of the sensors from the host structure under cyclic load. The printed pattern distinguishes superior performance in the perception of acousto-ultrasonic signals from static up to 500 kHz, with high signal-to-noise ratio, sensitivity, and fidelity. By virtue of the tunneling current between two adjacent nanoparticles that are in close proximity (within several nanometers), the printed sensor network is capable of perceiving ultrasonic waves. The fabrication process of the sensor network does not entail any specially made printing facilities, and the carbon black/polyvinyl pyrrolidone hybrid can easily be injected into an inkjet cartridge for printing. Several confirmatory experiments and a proof-of-concept test were carried out based on the printed sensor network to validate the capability of the printed sensor for structural health monitoring.

Although the Early Paleozoic tectonic framework of northern West Junggar is essential for understanding accretionary processes in the southwestern Central Asian Orogenic Belt, this setting is still not well understood. In order to address this issue, we employed detailed geochronological, geochemical and Sr-Nd-Hf-Os isotope analyses on the Hoboksar ophiolitic melange in northern West Junggar. The Hoboksar ophiolitic melange mainly consists of serpentinized peridotites, pyroxenites, gabbros, diabase, cherts, marbles, volcanic and pyroclastic rocks. It is characterized by a “block-in-matrix” structure with serpentinized peridotites as the matrix which is crosscut by later diorite porphyry and rhyolitic porphyry. Olivines and spinels in these serpentinized peridotites show high Fo# and Cr#, respectively. The clinopyroxenes in the pyroxenites exhibit high Mg#, low Al2O3 and Cr2O3. The serpentinized peridotites have extremely low rare-earth element (REE) abundances, U-shaped to flat REE patterns and positive Eu anomalies. Their particularly low Re/Os, initial 187Os/188Os and γOs(t) imply that they could represent residual phases after partial melting of upper mantle. The gabbros and diabases display slight fractionation between light REE and heavy REE, negligible Eu anomalies, depletion in Rb, Nb and Ta, enrichment in Th and U, low initial 87Sr/86Sr and positive eNd(t). The mineral and whole-rock geochemical and isotopic compositions of these ultramafic-mafic rocks demonstrate that the Hoboksar ophiolitic melange originated from a depleted mantle in a fore-arc supra-subduction zone (SSZ) setting. Zircon U Pb dating on diorite porphyry and rhyolitic porphyry yields weighted mean 206Pb/238U ages of 435 ± 4 Ma and 441 ± 2 Ma, respectively, postdating the closure of an ancient ocean represented by the Hoboksar ophiolite. These later intrusions resemble adakitic rocks with high Sr/Y. They exhibit mild depletion in Nb and Ti, low initial 87Sr/86Sr, positive eNd(t) and zircon eHf(t). Therefore the diorite porphyry and rhyolitic porphyry likely derived from juvenile lower crust. Based on our new data and other geologic evidence, we propose that the ancient Hoboksar Ocean resided between two Paleozoic arcs in northern West Junggar during the Early Ordovician, and this ocean was closed before 440 Ma. The emplacement of adakitic stitching intrusions implies a back-arc extensional setting that may be due to (present-day) northward subduction of the Junggar-Balkhash oceanic slab during the Early Silurian.

Certain traditional sensors like lead zirconate titanate (PZT) wafers and ultrasonic probes can respond to extremely weak disturbances such as ultrasonic guided waves (UGWs). However, their further development for applications to meet increasing engineering demands is limited on account of their hardness, brittleness, and complex manufacturing processes. Now, emerging nanotechnology ushers in a brand-new world for nanocomposite-based strain sensors, endowing them with higher flexibility, better surface compatibility and easier fabrication. Yet there are few reports of composites which can be used to perceive high frequency UGWs with an ultralow magnitude. Here, we present a novel graphene-based nanocomposite possessing strong sensitivity for sensing ultrasonic waves by virtue of a neoteric sensing mechanism − the tunneling effect. By designing and optimizing the microstructure of the conductive network in the nanocomposite sensor, we successfully capture ultrasonic waves with high signal-to-noise ratio in a broad frequency range up to 1 MHz. With the feature of high sensitivity and rapid response times, the graphene-based nanocomposite becomes a promising candidate for structural health monitoring in developing prospective applications.

Identification of delaminations in the early stage is crucial to ensure the safety of CFRP laminates. In the modal domain, high spatial sampling resolution of a mode shape is required for precise location of incipient delamination. Non-contact measurement relying on laser scanning technology allows measured mode shapes to be densely sampled. Unfortunately, noise components usually contaminate such densely-sampled mode shapes, easily causing intense noise interference that likely masks actual delamination features. To address this issue, a noise-robust damage indicator is formulated for designating the presence and location of incipient delamination in CFRP laminates under noisy environments. This damage indicator is created by introducing a 2D multi-resolution modal Teager-Kaiser energy for characterizing delamination-caused singularity of mode shapes. Proof of concept of the damage indicator is numerically undertaken in finite-element CFRP laminates with incipient delaminations, with emphasis on sensitivity to damage as well as robustness against noise. The applicability of the damage indicator is experimentally validated on a CFRP laminate with an incipient delamination, mode shapes of which are precisely acquired via the non-contact measurement using a scanning laser vibrometer. The numerical and experimental results show that the damage indicator can effectively identify the presence and location of incipient delamination in CFRP laminates under noisy environments.

The surficial sediment samples collected from the Sanggou Bay in China were treated by a sequential extraction procedure. After removal of calcite, organic matter and Fe/Mn oxides, P adsorption onto the sediment residues was then evaluated through kinetic and thermodynamic characteristics. The sorption kinetic curves could be described by a two-compartment first order equation. The sorption isotherms fit well with the Langmuir and Freundlich equations. The HCl-treated sediments with calcite removed showed a rising fraction of the rapid step and a higher P adsorption potential compared with the un-extracted samples. For the clay minerals and silicate residue after NH2OH·HCl treatment, the rapid step fraction was dominant, the sorption capability was prohibited, and the process was much more reversible than the original and previously-generated samples. An increase of temperature was favorable for the sorption. Estimation of thermodynamic parameters showed that the process was spontaneous and endothermic, with an increased randomness at the solid-liquid interface. Compared with the un-extracted sediment, the thermodynamic parameters in our case changed slightly after HCl treatment and NH2OH·HCl treatment.

The present nonprecious hydrogen evolution electrocatalysts deliver high activity either in acid or alkaline media, indicating the urgent demand for development of pH-universal catalysts. In this work, we report a high-performance electrcatalyst based on ternary iron phosphoselenide (FePSe3) nanoparticles anchored on N-doped carbon framework for hydrogen evolution reaction (HER) in acidic, neutral and basic media. The FePSe3 nanoparticles with metallic nature enable to fully utilize accessible edge sites, and the highly open yet interconnected three-dimensional framework creates large surface area, exposing abundant active sites and providing convenient charge/ionic diffusion pathway. DFT calculations reveal the synergistic electronic interaction between Se and P, leading to optimal electronic structures and hydrogen adsorption free energy on Fe, P and Se sites, thus facilitating HER kinetics. As a result, the obtained FePSe3/NC exhibits superior HER activities with low overpotentials of 70, 140.1 and 118.5 mV to afford 10 mA cm−2 current density in acidic, neutral and basic media, as well as robust stability in all-pH range. This work highlights the dual-anion effect to radically construct all-pH HER electrocatalysts.

We present a nano-engineered thin-film-type piezoresistive sensor, coatable or sprayable on a medium surface for in-situ acquisition of broadband ultrasound up to 1.4 MHz – a trait of nanocomposite-based piezoresistive sensing devices that has until now not been discovered and explored. With polyvinylidene fluoride as the matrix, fabrication of the spray-on sensor is attempted in a comparative manner, with multiscale nanofillers ranging from zero-dimensional carbon black, through one-dimensional multiwalled carbon nanotubes, to two-dimensional graphene nanoparticles. With a morphologically optimal nano-architecture, the quantum tunneling effect can be triggered in the percolating nanofiller network when ultrasound signals traverse the sensor, inducing dynamic alteration in the piezoresistivity manifested by the sensor. In-situ morphological analysis and experiment reveal high fidelity, ultrafast responses, and high sensitivity of the sensor to dynamic disturbance, from static strain to ultrasound in a regime of megahertz yet with an ultralow magnitude (of the order of microstrain or nanostrain). These findings are remarkable as no other investigation has probed the response of nanocomposite piezoresistive sensors over such a broad frequency spectrum.

Developing noble-metal-free electrocatalysts with high efficiency and low cost in the all-pH range is highly desired but challenging. Herein, we constructed the hybrid interface structure of NiSe2 ...

Sodium-ion batteries (SIBs) are faced with several challenges, including low capacity, short cycle life, and poor low-temperature performance. In this work, TiO2-B/anatase dual-phase nanowires are synthesized and applied as SIB anodes to address the above challenges. For the first time, we find the excellent Na-storage performance of the nanowire anode like rate-independent capacities and ultra-stable cycling stability at low temperature. Operando Raman spectroscopy shows that the nanowires are completely amorphized after cycling at 303 K; however, the TiO2-B phase of the dual-phase nanowires remains crystalline after cycling at 273 K. The different sodiation mechanisms at different temperatures result in a lower capacity but a more stable structure during cycling at 273 K than at 303 K. Kinetic analysis shows that the nanowire anode possesses an ultralow charge-transfer energy barrier and resistance with a higher apparent Na diffusion coefficient at 273 K than at 303 K during desodiation, which significantly enhances the Na+ intercalation pseudocapacitive process at low temperature. The synergy between the structural transition and diffusion kinetics leads to rate-independent and ultra-stable Na-storage performance at low temperature. This work provides new perspectives for the understanding and design of low-temperature SIBs with high rate capability and long cycle life.

To balance the electrochemical performance gap between the Li+ insertion/deintercalation anode and the anion adsorption/desorption cathode, in this paper, for the first time, we investigated MnNb2O6 as a new rate capability type anode material for lithium-ion capacitors (LICs). Novel calendula-like MnNb2O6 particles anchored on reduced graphene oxide (rGO) were prepared via a simple two-step hydrothermal route. The special three-dimensional structure and cross-linked conductive network constructed by graphene could shorten the lithium-ion diffusion path, efficiently facilitate electron transmission and adapt to volume strain without shedding during the long-term charge/discharge process. This resulted in excellent charge storage capacity and reasonably superior cycling stability. MnNb2O6@rGO//AC LICs assembled with MnNb2O6@rGO as the cathode and activated carbon (AC) as the anode exhibited excellent performance with maximum energy density of 118 W h kg−1 and power density of 8000 W kg−1 based on the total mass loading of the active material weight. The initial capacity retention was up to 88% after 10 000 charge/discharge cycles, which was higher than that of bimetallic oxide materials reported so far. Therefore, this study might provide a novel rate capability anode material for LICs with high performance.

With the development of human healthcare devices, smart sensors, e-skins, and pressure sensors with outstanding sensitivity, flexibility, durability and biocompatibility have attracted more and more attention. In this paper, to develop a novel flexible pressure sensor with high sensitivity, different poly (vinylidene fluoride-trifluoroethylene) (PVDF-TrFE)-based composite membranes were fabricated, characterized and tested. To improve the β-phase crystallinity and piezoelectricity of the membranes, and for the purpose of comparison, nano ZnO particles with different concentrations (99:1, 9:1 in a weight ratio of PVDF-TrFE to ZnO) were, respectively added into PVDF-TrFE polymer acting as a nucleating agent and dielectric material. To facilitate the formation of β-phase crystal, the membranes were fabricated by electrospinning method. After the electrospinning, an annealing process was conducted to the fabricated membranes to increase the size and content of β-phase crystal. Then, the fabricated PVDF-TrFE membranes, acting as the core sensing layer, were, respectively built into multiple prototype sensors in a sandwich structure. The sensitivity of the prototype sensors was tested by an auto-clicker. The stimulation of the auto-clicker on the prototype sensors generated electrical signals, and the electrical signals were collected by a self-built testing platform powered by LabVIEW. As a result, combining the addition of ZnO nanofillers and the annealing process, a highly sensitive pressure sensor was fabricated. The optimal peak-to-peak voltage response generated from the prototype sensor was 1.788 V which shows a 75% increase compared to that of the pristine PVDF-TrFE sensor. Furthermore, a human pulse waveform was captured by a prototype sensor which exhibits tremendous prospects for application in healthcare devices.

Aim The present study aimed to assess the benefits of two-stent techniques for patients with DEFINITION criteria-defined complex coronary bifurcation lesions. Methods and results In total, 653 patients with complex bifurcation lesions at 49 international centres were randomly assigned to undergo the systematic two-stent technique (two-stent group) or provisional stenting (provisional group). The primary endpoint was the composite of target lesion failure (TLF) at the 1-year follow-up, including cardiac death, target vessel myocardial infarction (TVMI), and clinically driven target lesion revascularization (TLR). The safety endpoint was definite or probable stent thrombosis. At the 1-year follow-up, TLF occurred in 37 (11.4%) and 20 (6.1%) patients in the provisional and two-stent groups, respectively [77.8%: double-kissing crush; hazard ratio (HR) 0.52, 95% confidence interval (CI) 0.30–0.90; P = 0.019], largely driven by increased TVMI (7.1%, HR 0.43, 95% CI 0.20–0.90; P = 0.025) and clinically driven TLR (5.5%, HR 0.43, 95% CI 0.19–1.00; P = 0.049) in the provisional group. At the 1 year after indexed procedures, the incidence of cardiac death was 2.5% in the provisional group, non-significant to 2.1% in the two-stent group (HR 0.86, 95% CI 0.31–2.37; P = 0.772). Conclusion For DEFINITION criteria-defined complex coronary bifurcation lesions, the systematic two-stent approach was associated with a significant improvement in clinical outcomes compared with the provisional stenting approach. Further study is urgently warranted to identify the mechanisms contributing to the increased rate of TVMI after provisional stenting. Study registration http://www.clinicaltrials.com; Identifier: NCT02284750.

Inspired by people to make flour food, a one-pot, low-cost, green and environmental friendly gas foaming strategy is adopted here to prepare the three-dimensional hierarchical porous carbon (HPC) by introducing NaHCO3 as foaming and activation agent. During the pyrolysis process, the CO2 gas produced during the transforms from NaHCO3 into Na2CO3 will resulted in the producers of the macro-pores and meso-pores, meanwhile, the as-produced Na2CO3 further reactor with the carbon intermediate at a high temperature, and finally result in forming a micro-pores porous structure. Such intimate structural interconnectivities provide three-dimensional continuous pathway for electron rapid transfer and the interconnected pores allow for the ion to penetrate and evenly contact the electrode material quickly. The electrochemical performance of HPC exhibits a high specific capacitance of 350 F g−1 at 1 A g−1 and outstanding electrochemical stability with capacitance retention up to 97% after 10,000 cycles. Moreover, the as-assembled symmetric supercapacitor exhibits an ultrahigh energy density of 27.4 Wh kg−1, much higher than most of carbon-based supercapacitors. These results demonstrate a straightforward environment friendly method to mass-produce economical, robust carbon materials as promising candidates for supercapacitor application.

Lithium sulfur batteries with high energy densities are promising next-generation energy storage systems. However, shuttling and sluggish conversion of polysulfides to solid lithium sulfides limit the full utilization of active materials. Physical/chemical confinement is useful for anchoring polysulfides, but not effective for utilizing the blocked intermediates. Here, we employ black phosphorus quantum dots as electrocatalysts to overcome these issues. Both the experimental and theoretical results reveal that black phosphorus quantum dots effectively adsorb and catalyze polysulfide conversion. The activity is attributed to the numerous catalytically active sites on the edges of the quantum dots. In the presence of a small amount of black phosphorus quantum dots, the porous carbon/sulfur cathodes exhibit rapid reaction kinetics and no shuttling of polysulfides, enabling a low capacity fading rate (0.027% per cycle over 1000 cycles) and high areal capacities. Our findings demonstrate application of a metal-free quantum dot catalyst for high energy rechargeable batteries., Lithium sulfur batteries are promising for next-generation energy storage, but are hindered by polysulfide shuttle effects. Here the authors use black phosphorus quantum dots to adsorb and catalyze the conversion of lithium polysulfides to lithium sulfide, achieving low capacity fade and high sulfur loading.

Concentrations and diurnal variations of inorganic nutrients (dissolved inorganic nitrogen (DIN), phosphate (PO4-P) and silicate (SiO3-Si)), as well as chlorophyll a (Chl-a) were determined in the subsurface water (SSW) and surface microlayer (SML) of the Bohai and Yellow Seas in summer 2015. The concentrations of DIN, SiO3-Si and Chl-a (except for PO4-P) in the SML were respectively correlated with their concentrations in the SSW, indicating that a major source of substances in the SML could be transported from the SSW. The enrichment factor (EF) was defined as the ratio of the concentration in the SML to that in the corresponding SSW. There was little difference in concentrations of PO4-P between the SML and the SSW samples by nonparametric difference test (P > 0.05). DIN, SiO3-Si and Chl-a (except for PO4-P) were found to be enriched in the SML relative to the SSW, with average EFs of 2.45, 1.18 and 2.37, respectively. No connection was identified between nutrients EFs and wind speed for our entire data. DIN, SiO3-Si, PO4-P and Chl-a concentrations in the SSW and the SML exhibited strong diurnal variations at an anchor station.

The flexible solid-state supercapacitor (FSSC) has attracted many attentions due to its feature of high power density with stable cycling performance, as well as lightweight and flexible features and is expected as an ideal candidate power supply for portable and wearable electronics devices. In general, the electrode plays an important role in determining the overall performance of the FSSC. Therefore, to meet the requirement of practical applications, a simple, facile and environment friendly strategy to prepare deformable/flexible electrodes with high energy density is the target issue to be considered. Herein, we report a generalized “soaking-recrystallization-calcination” method to enhance the capacitance performance of commercialized carbon fiber cloth. Thanks to the in-situ etching process to increase the surface area and the synchronous heteroatom doping to induce pseudocapacitive behavior, the resultant activated carbon fiber cloth sample exhibits an ultra-high areal capacitance up to 362 mF cm−2, is about 1448 fold enhancement than that of fresh carbon fiber cloth calcined at 750 °C. Meanwhile, the assembled FSSC based on the activated carbon fiber cloth exhibits a maximum volumetric energy density of 0.35 mWh cm−3 and gravimetric energy density of 0.84 Wh kg−1. Such results represent a novel and promising direction to prepare high performance flexible electrode for FSSC application.

Objective: To investigate the relationship between polymorphisms of rs1532624 and rs289741 loci in cholesteryl ester transfer protein (CETP) genes and atherosclerotic cerebral infarction (ACI). Methods: The CETP gene rs1532624 and rs289741 in 95 patients with ACI and 177 healthy subjects were genotyped by MassARRAY mass spectrometry. Each locus genotype and allele frequency distributions were compared. Results: The difference of allele frequency distribution between the rs1532624 (χ2=1.723, P =0.189) and rs289741 (χ2=2.466, P =0.116) were not statistically significant. The frequency distribution of rs1532624 genotype between the cerebral infarction group and healthy control group was statistically significant (χ2=7.096, P =0.029), while rs289741 genotype frequency distribution between the two groups was not statistically significant (χ=2.906, P =0.234). Conclusion: ACI have a positive correlation with rs1532624 polymorphism, and AA genotype may be susceptible factors of ACI.

To improve the ultrasonic imaging of composites, an all-printed nanocomposite sensor array (APNSA) is developed using a direct-write approach. Individual sensing elements of APNSA are inkjet printed by directly writing graphene/poly (amic acid) (PAA)-based nanocomposite ink on Kapton film substrates, with an ultra-thin thickness of ∼1 μm only. APNSA is morphologically tuned at a nano scale to be sensitive to acousto-ultrasonic waves of a broad band regime. Each sensing element features a homogenous and consolidated nanostructure , with which transient change of tunneling resistance between adjacent graphene nanoplatelets in the polyimide (PI) matrix can be triggered when the element is loaded with acousto-ultrasonic waves. The triggered quantum tunneling effect endows APNSA with capability to perceive dynamic strains in a broadband regime with high fidelity and accuracy. Compared with a conventional ultrasonic phased array which is of a low degree of compatibility with composites, APNSA can be fully integrated with the inspected composites. In conjunction with the use of the additively manufactured APNSA, ultrasonic imaging of composites can be implemented, spotlighting a nature of full integration of APNSA with composites for in situ structural health monitoring and anomaly detection, yet without degrading the original integrity of the composites.

We report a carbon-sulfur nanostructure by impregnating sulfur into activated N-doped hollow carbon nanofibers (ANHCNFs) with a high Brunauer-Emmett-Teller (BET) specific surface area of 608 m 2 g −1 and a total pore volume of 0.8 cm 3 g −1 . As a cathode, this material with 50 wt% sulfur shows a reversible capacity of 1230 mAh g −1 and maintains ∼920 mAh g −1 after 100 cycles at 0.2 C (1 C = 1675 mA g −1 ). These results show that the ANHCNFs-S could be a superior cathode material for Li-sulfur battery.

The interfacial failure behavior of sisal fiber-reinforced composites (SFRCs) was studied experimentally and theoretically. The residual pull-out strength of the SFRCs was observed to gradually decrease during the single sisal fiber pull-out test, after which the SFRCs presented multiple failure modes, including at the interface between technical fiber and matrix and at the interface between elementary fibers. To further investigate the failure mechanisms of SFRCs, using the traditional shear lag model, a double-interface model tailored to the unique multi-layer interface structure of plant fibers was developed to describe the fiber pull-out behavior and the interfacial adhesion status of single plant fiber-reinforced composites (PFRCs). By comparison with other existing models, using the experimental applied stress as reference, the proposed double-interface model was found to provide a more accurate quantitative theoretical prediction of the interfacial failure behavior of PFRCs during multi-stage fracture of the two interfaces.

The development of additive manufacturing (AM) has revolutionized the fabrication process of continuous fiber reinforced polymer (CFRP) composites with its outstanding ability to create products that are complex in material, structure, and function. However, existing studies mostly focus on the manufacturing process without paying sufficient attention to exploring new design opportunities enabled by CFRP-AM. This paper outlines the design concept for additive manufacturing of continuous fiber reinforced polymer composites, aiming to improve existing products' performance and foster product innovations for future needs. More specifically, existing CFRP-AM techniques are reviewed from the perspective of functional requirements. Design opportunities within the material, process, and structure domains are identified. Also, novel applications enabled by design for CFRP-AM on shape morphing, sensing, and energy storage are presented. The review concludes with a brief discussion and an outlook on future work.

Extra to serving as the reinforcement in polymer-based composites, glass fibres (GFs) are decorated with dense and uniform carbon nanotubes (CNTs) via chemical vapor deposition at a low CNT growth temperature (500 °C ). The hairy CNT-decorated GF bundles measure the dynamic variation in electrical resistance using CNT-formed piezoresistive networks in the bundles, with which the resin flow front and cure progress of epoxy during fabrication are self-monitored by the composites. The bundles also precisely sense in-service loads applied to the composites, with a gauge factor as high as 30.2. Without intrusion to the original composites from sensors and sensor-associated electrodes/cables, the CNT-decorated GF bundles shed light on the use of nanocomposite-driven fibre decoration towards development of new functional composites.

The interfacial strength and electrochemical performance of composite structural battery can be simultaneously enhanced by employing modified carbon fibers (MCFs) as electrode. In this study, an electrochemical-mechanical coupled modeling framework is developed to clarify the multiphysics nature of composite structural battery and guide their further optimal design. Effects of the thickness ratio of cathode to anode, electrode thickness and the volume ratio of modified layer on CFs for the electrochemical and mechanical properties are investigated. An optimal thickness ratio of MCFs cathode to anode exists for better electrochemical performance, while thinner MCFs electrode will trigger greater specific capacity. In addition, the volume fraction of carbon fiber in composites and that of modified layer on CF respectively dominate longitudinal modulus and electrochemical capacity.

Dual ion battery (DIB) with graphite cathode is a renewable energy storage system but suffers from low capacity. Addition of lithium ion battery (LIB) cathode to graphite cathode not only facilitates capacity increment but also serves as proof-of-concept for LIB-DIB hybridization. In this study, a hybrid cathode, incorporating a physical mixture of high working potential graphite and nontoxic lithium iron phosphate (LiFePO4, LFP), is proposed and examined. The graphite interacts with anion and works as electrically conductive matrix. While additive LFP is active to cation, serving as capacity facilitator. Characterization results reveal that, during charging, the hybrid cathode starts with LFP delithiation in lower voltage region and finishes with anion intercalation in graphite at higher voltage region. During discharging, processes are reversed with stepwise anion deintercalation and cation insertion, without interfering individual constituent's proper functioning. The transfer of two polarity distinct ions inside the hybrid cathode maintains high independence, without any added kinetical difficulties. Such hybrid cathode is demonstrated to work stably with varied LFP-graphite proportions. The addition of 40 wt% LFP to graphite cathode shows doubled capacity and excellent long-term cyclability. And the hybrid cathode is also cyclable in a full cell configuration.

Owing to low cost and natural abundance of sodium reserves, sodium-ion batteries (SIBs) are attracting increasing attention and become promising alternatives to lithium ion batteries (LIBs). Based on merits of high structure stability and superb conductivity, nanocomposites have been widely investigated for SIB electrodes. However, SIBs still face some significant issues like serious side reactions, low energy density, and poor cycling life. Further improvement of the electrochemical performance needs definitely a deep understanding of structural and kinetic process occurred in these nanocomposite electrodes during charging/discharging processes. Recently, a diversity of in-situ techniques has emerged to investigate the inner phenomena occurred. In this short review, we summarize the state-of-the-art in-situ techniques, including in-situ transmission electron microscopy (TEM), in-situ X-ray diffraction (XRD), in-situ X-ray absorption spectroscopy (XAS), and in-situ Raman spectroscopy, applied to the characterization of morphological evolutions, mechanical/chemical changes, and phase transitions of these nanocomposite electrodes during electrochemical sodiation/de-sodiation processes. Finally, we also discuss limitations and future opportunities of in-situ technologies in nanocomposite materials for SIBs. The review aims at better understanding of these in-situ techniques for researchers in the society of SIBs, and is expected to provide guidance of nanocomposites for other fields.

The multi-layer structure of plant fibers has been revealed qualitatively by qualitative microscopic characterization and associated with multi-stage failure behaviors of plant fiber reinforced epoxy composites. To quantitatively evaluate the nanoscopic mechanical properties of sisal fiber (a typical plant fiber) reinforced epoxy composites (SFRCs) involving the unique structural characteristics, elastic modulus and hardness of the epoxy matrix and cell wall layers of sisal fiber along with interfacial mechanical properties were measured by applying the nanoindentation technique. A series of indents were conducted at selected positions from the matrix to each layer of the fiber cell walls to ascertain transition zones of the multi-layer interfaces. Single-step and multi-step nanoindentation methods were respectively employed on the multi-layer interfaces of SFRCs to present their distinct mechanical properties in terms of modulus and hardness, energy dissipation, crack initiation and propagation upon compressive loading. This study measures the transition zones of the multi-layer interface and the interfacial failure load, which consequently facilitates a quantitative analysis of fracture mechanisms for SFRCs with a multi-scale and multi-layer structure.

Nanocomposites fabricated based on a compound of carbon nanofiller and polymer matrix exhibit extraordinary piezoresistive performance, and the capacity of nanocomposite sensors in measuring structural dynamic strains has been widely demonstrated. However, the sensitivity of existing nanocomposite strain sensors is limited, particularly in aspects of sensing precision and response frequency. This study focuses on sensitivity investigations of flexible nanocomposite sensors fabricated using a compound of carbon black (CB) fillers and polyvinylidene fluoride (PVDF) matrix, which has shown promising potential in perceiving extremely weak strain signals within a considerably broad range of response frequencies. As a highly important indication of sensitivity, sensing precision was characterized in a quantitative manner. Broadband spectrum analysis was conducted as an effective way to examine sensor performance in perceiving minimal disturbances in dynamic strains. Disturbances were generated in two experiments, by introducing local material and geometric variations into the inspected structures, in terms of mass attachment and structural damage. The effectiveness of the nanocomposites in structural damage detection was demonstrated. Moreover, the experimental results indicate the promising potential of nanocomposite-based strain sensors for applications such as advanced bioelectronics, ultrasonic inspection, and in - situ structural health monitoring.