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The characteristics of the interface are the key factors that determine the mechanical properties and fracture behavior of fiber-reinforced ceramic matrix composites. Design and preparation of coatings which can preserve fiber strength and maintain appropriate interfacial bonding strength are of great challenges. LaPO4 coating is a promising weak interface coating for oxide fiber reinforced oxide ceramic matrix composites. Through this coating, the toughening mechanism of the composite such as fiber pulling out and fiber debonding is triggered. The LaPO4 coating was deposited on the surface of alumina-based fibers by a solution precursor heterogeneous precipitation method. The effects of different precursors and different deposition temperatures on fiber strength were studied, and the mechanism of the strength degradation of the coated fiber was analyzed. It was found that the fibers coated with phytic acid precursor and deposited at 90 °C had the highest tensile strength compared to other coated fibers. The retention of strength is attributed to its loosely stacked coating. Besides, a single fiber pullout test was carried out to evaluate the effect of the coating on the interface of the composites. The results show that the composites coated by depositing citric acid precursor and phytic acid precursor at 90 °C can reduce the interfacial bonding strength by 32.5% and 46.7%, respectively compared to uncoated composites. This study has potential application value in the preparation of ceramic matrix composites used in oxidation and high temperature environments.

We report on the effect of spatially correlated noise on the velocities of self propelled particles. Correlations in the random forces acting on self propelled particles can induce directed collective motion, i.e. swarming. Even with repulsive coupling in the velocity directions, which favors a disordered state, strong correlations in the fluctuations can align the velocities locally leading to a macroscopic, turbulent velocity field. On the other hand, while spatially correlated noise is aligning the velocities locally, the swarming transition to globally directed motion is inhibited when the correlation length of the noise is nonzero, but smaller than the system size. We analyze the swarming transition in $d$ dimensional space in a mean field model of globally coupled velocity vectors., Comment: 8 pages, 2 figures (9 panels), to appear in APS Physical Review E

As a hybrid energy storage device of lithium-ion batteries and supercapacitors, lithium-ion capacitors have the potential to meet the demanding needs of energy storage equipment with both high power and energy density. In this work, to solve the obstacle to the application of lithium-ion capacitors, that is, the balancing problem of the electrodes kinetic and capacity, two electrodes are designed and adequately matched. For the anode, we introduced in situ carbon-doped and surface-enriched unsaturated sulfur into the graphene conductive network to prepare transition metal sulfides, which enhances the performance with a faster lithium-ion diffusion and dominant pseudocapacitive energy storage. Therefore, the lithium-ion capacitors anode material delivers a remarkable capacity of 810 mAh·g−1 after 500 cycles at 1 A·g−1. On the other hand, the biomass-derived porous carbon as the cathode also displays a superior capacity of 114.2 mAh·g−1 at 0.1 A·g−1. Benefitting from the appropriate balance of kinetic and capacity between two electrodes, the lithium-ion capacitors exhibits superior electrochemical performance. The assembled lithium-ion capacitors demonstrate a high energy density of 132.9 Wh·kg−1 at the power density of 265 W·kg−1, and 50.0 Wh·kg−1 even at 26.5 kW·kg−1. After 10000 cycles at 1 A·g−1, lithium-ion capacitors still demonstrate the high energy density retention of 81.5%.

The mechanical properties of alumina AF17-20 fiber after high-temperature treatment have been evaluated through tensile tests on single fiber and bundle. The tensile test on single fibers shows that the temperature has little effect on the elastic modulus of the fibers, which stables around 140 GPa. The test on bundles minimizes the personal errors thus giving a more reliable value of tensile strength. In general, as temperature increases, both the Weibull modulus and the tensile strength decrease gradually. De-sized fibers have the highest tensile strength, but inherent defects like pores still cause slight dispersion of the strength. Further, the strength maintains about 90% after treating below 1200 °C, and this insignificant decline is caused by the decrease of amorphous SiO2 and the formation of aluminum silicate. In addition, the severe degradation in strength over 1200 °C is mainly attributed to the appearance and growth of mullite grains, which is only about 60% of the initial value.

The emergency of high-power electrical appliances has put forward higher requirements for the power density of lithium-ion batteries. Vanadium oxides with large theoretical capacities and high operating voltages are considered as prospective alternatives for the cathode of a new generation of lithium-ion batteries. However, the poor rate and cycling performance caused by the sluggish electrons/lithium transportation, irreversible phase changes, vanadium dissolution and large volume changes during the repeated lithium intercalation/deintercalation hinder their commercial development. Several optimizing routes have been carried out and extensively explored to address these problems. Taking V2O5, VO2(B), V6O13, and V2O3 as examples, this article reviewed their crystal structures and lithium storage reactions. Besides, recent progress in modification methods for the electrochemical insufficiencies of vanadium oxides, including nanostructure, heterogeneous atom doping, composite and self-supported electrodes has been systematically summarized and finally, the challenges for the industrialization of vanadium oxide cathodes and their development opportunities are proposed.

Oxide ceramics have excellent high temperature performance, superior thermal and chemical stability, which can be used in high temperature oxidizing environments, while oxide ceramics generally have low toughness and are prone to catastrophic damage... Oxide ceramics can be reinforced by high performance ceramic fibers to improve the fracture strength and fracture toughness, thus expanding its application in high-temperature components such as aero-engine combustion chambers and tail nozzles. The interface between fiber and matrix is an important factor that determines the performance of the composites. By tailoring the interface, the energy dissipation mechanisms such as fiber debonding and fiber pull-out can be brought into play to avoid the catastrophic damage of the composites. This review paper summarizes the recent research progress of the oxide fiber/oxide ceramic matrix composites interface. The mechanical properties of the interface and the design principles of the interface engineering are discussed, and types of interfaces and coating preparation methods are reviewed.

Lithium-ion batteries (LIBs) have evolved into the mainstream power source of energy storage equipment by reason of their advantages such as high energy density, high power, long cycle life and less pollution. With the expansion of their applications in deep-sea exploration, aerospace and military equipment, special working conditions have placed higher demands on the low-temperature performance of LIBs. However, at low temperatures, the severe polarization and inferior electrochemical activity of electrode materials cause the acute capacity fading upon cycling, which greatly hindered the further development of LIBs. In this review, we summarize the recent important progress of LIBs in low-temperature operations and introduce the key methods and the related action mechanisms for enhancing the capacity of the various cathode and anode materials. It aims to promote the development of high-performance electrode materials and broaden the application range of LIBs.

Hypersensitivity pneumonitis (HP) is a common type among all the interstitial lung diseases, and transbronchial lung cryobiopsy is an alternative diagnostic technique for interstitial lung diseases. In this study, we describe the clinical and pathological features of fibrotic hypersensitivity pneumonitis diagnosed with transbronchial lung cryobiopsy (TBLC).A total of 46 diffused parenchyma lung disease (DPLD) patients received TBLC were included in this study. Medical records including medical history spirometry examinations, 6-min walk test (6MWT) results, high resolution computed tomographic (HRCT) scans, BAL, and histopathology were collected. Results of HRCT and histopathology were compared and classified, especially.Sixteen patients were diagnosed with fibrotic HP, the mean age of whom was 56.3 ± 12.1 years, and 62.5% of them were male. Three of the 16 patients had been misdiagnosed as tuberculosis and received antituberculosis medications, five patients had been diagnosed as unclassifiable pulmonary fibrosis, and five patients had been diagnosed as idiopathic pulmonary fibrosis (IPF). Thirteen (81.3%) patients had a normal lymphocyte count in BAL. The pathological features of usual interstitial pneumonia (UIP) were detected in 11 (68.8%) of the cases, poor defined granulomatous was detected in nine (56.3%) of the cases, and bronchiolocentric fibrosis was detected in two (12.5%) of the 16 cases.Fibrotic hypersensitivity pneumonitis should be included in differential diagnosis of pulmonary fibrosis. Pathological characteristics of fibrotic hypersensitivity pneumonitis could be demonstrated from cryobiopsy lung tissue. TBLC is recommended as an alternative diagnostic technique, which may improve the specificity of hypersensitivity pneumonia detection, and UIP is the most frequent pathological finding.

Background Anxiety and depression are common comorbidities in COPD patients but are often under-diagnosed. We aimed to assess the value of the COPD Assessment Test (CAT) in identifying anxiety and depression from patients with COPD. Methods Stable COPD patients were recruited in this cross-sectional observational study between December 2016 and January 2021. The demographic characteristics and the CAT score were recorded. Anxiety was measured using Generalized Anxiety Disorder Questionnaire (GAD)-7. Depression was measured by Patient Health Questionnaire (PHQ)-9. Logistic regression analysis and receiver operating characteristic curve analysis were performed to identify factors associated with anxiety or depression and to calculate the predictive values. Results A total of 530 stable COPD patients were enrolled and of those the proportion of anxiety and depression were 17.0% and 21.5%, respectively. The CAT score correlated well with the GAD-7 score (r = 0.339, P

Three-dimensional (3D) printing technology is becoming a promising method for fabricating highly complex ceramics owing to the arbitrary design and the infinite combination of materials. Insufficient density is one of the main problems with 3D printed ceramics, but concentrated descriptions of making dense ceramics are scarce. This review specifically introduces the principles of the four 3D printing technologies and focuses on the parameters of each technology that affect the densification of 3D printed ceramics, such as the performance of raw materials and the interaction between energy and materials. The technical challenges and suggestions about how to achieve higher ceramic density are presented subsequently. The goal of the presented work is to comprehend the roles of critical parameters in the subsequent 3D printing process to prepare dense ceramics that can meet the practical applications.

N-Boc deprotection (deBoc) is a common reaction in pharmaceutical research and development, as well as pharma manufacturing. Use of a catalyst lowers the required reaction temperature, and heterogeneous catalysts allow the reaction to be conducted in a continuous flow reactor with a low-boiling solvent, facilitating product separation and enhancing efficiency and productivity relative to a batch process. In this study, we explore the use of simple solid Bronsted acid catalysts to achieve continuous N-Boc deprotection of amines, without additional workup steps. Using THF as the solvent, H-BEA zeolite affords high yields of a variety of aromatic and aliphatic amines, often in residence times of less than a minute at 140 °C. The same catalyst/solvent combination is ineffective in batch conditions, due to the much lower temperature of refluxing THF. Boc-protected p-chloroaniline was deprotected with a throughput of 18 mmol p-chloroaniline per h per gcat, sustained over 9 h. The active sites of the zeolite do not appear to be directly associated with the Al framework substitution in the micropores, since partially ion-exchanged Na/H-BEA shows activity similar to H-BEA. The strong Bronsted acid sites (framework [Si(OH)Al]), are likely poisoned by the amine product. Moderate Bronsted acid sites associated with silanol defects near Al on or near the external surface (and not susceptible to Na+-exchange) are presumably the active sites, since they are not poisoned even by more basic aliphatic amines.

ObjectivesTelomerase gene variants that lead to accelerated telomere shortening are linked to progressive-fibrosing interstitial lung diseases. However, little is known about their relationships with pneumoconiosis. This study aimed to identify TERT/TERC variants and leucocyte telomere lengths (LTL) in patients with silicosis or asbestosis.MethodsIn the present study, Sanger sequencing of TERT/TERC variants was performed in 193 Chinese Han patients with pneumoconiosis, including 109 with silicosis and 84 with asbestosis. Quantitative PCR was used to measure LTL in peripheral blood of the patients and 200 age and sex-matched healthy controls.ResultsIn total, 7.3% patients with pneumoconiosis had 17 TERT/TERC variants. Among which 8.3% of patients with silicosis and 3.6% of patients with asbestosis had TERT variants, respectively. No TERC variants were detected in silicosis, whereas 3.6% of patients with asbestosis had TERC variants. Telomeres were significantly shorter in the patients with pneumoconiosis compared with healthy controls (pTERT/TERC variant carriers and non-carriers. Exposure to silica dust was associated with the severity of pneumoconiosis after adjusting for covariates (OR 4.92, p=0.002). However, TERT/TERC variants and short telomeres were not associated with the severity of pneumoconiosis.ConclusionTelomerase gene variants and short telomeres may be identified in the patients with silicosis and asbestosis in response to the exposure to silica or asbestos dust but are not related to disease severity.

SnS2 stands out to be a potential anode material for sodium-ion batteries (SIBs) owing to its high theoretical capacity and earth abundance. Nevertheless, the severe volume expansion and aggregation of SnS2 would lead to low reversible capacity and poor rate capability. Herein, SnS2 quantum dots uniformly anchored on dispersed S-doped graphene were designed and synthesized via a simple hot bath process with the addition of K+ (K-SnS2@SG). Dispersed S-doped graphene can not only increase the electric conductivity and mitigate the large volume expansion, but also accelerate the electronic/ionic transportation and improve the electrochemically active sites for Na+ storage. Uniformly distributed SnS2 quantum dots can shorten the transfer and diffusion path of Na+/electrons, and the abundant voids around quantum dots can relieve much of volume expansion and keep SnS2 from aggregating. Accordingly, the K-SnS2@SG electrode delivers a high reversible capacity (743 mAh g−1 at 45 mA g−1) and superior rate capability (236 mAh g−1 at 27 A g−1). Furthermore, the kinetic analyses demonstrate that the dominant capacitive behaviors account for excellent rate capability.

MnS as anode material for sodium-ion batteries (SIBs) has recently attracted great attention because of the high theoretical capacity, great natural abundance, and low cost. However, it suffers from inferior electrical conductivity and large volume expansion during the charge/discharge process, leading to tremendous damage of electrodes and subsequently fast capacity fading. To mitigate these issues, herein, a three-dimensional (3D) interlaced carbon nanotubes (CNTs) threaded into or between MnS hollow microspheres (hollow MnS/CNTs composite) has been designed and synthesized as an enhanced anode material. It can effectively improve the electrical conductivity, buffer the volume change, and maintain the integrity of the electrode during the charging and discharging process based on the synergistic interaction and the integrative structure. Therefore, when evaluated as anode for SIBs, the hollow MnS/CNTs electrode displays enhanced reversible capacity (275 mAh/g at 100 mA/g after 100 cycles), which is much better than that of pure MnS electrode (25 mAh/g at 100 mA/g after 100 cycles) prepared without the addition of CNTs. Even increasing the current density to 500 mA/g, the hollow MnS/CNTs electrode still delivers a five times higher reversible capacity than that of the pure MnS electrode. The rate performance of the hollow MnS/CNTs electrode is also superior to that of pure MnS electrode at various current densities from 50 mA/g to 1000 mA/g.

Dopamine is an important neurotransmitter for organisms and affects their function, so monitoring and detecting dopamine levels are essential. Sensitivity and selectivity of electrochemical sensors for the detection of dopamine usually rely on hybrid nanocomposites. In this context, we designed a micro-regionally restricted hybrid nanocomposite by modulating the micro-nano structure. Using functional groups on nitrogen-doped reduced graphene oxide (N-rGO) to restrict the random growth of tungsten disulfide nanosheets, we obtained a 2D layered material with bidirectional structural support to achieve high specific surface and high activity for application in robust and novel dopamine electrochemical sensors. A facile electrochemical sensor for dopamine detection was fabricated by modifying a screen-printed carbon electrode with the nanocomposite. The sensor exhibits excellent performance of dopamine detection in the wide range of 1 μmol l−1–100 μmol l−1 with a detection limit of 0.2 μmol l−1 and a high sensitivity of 0.56 μA μmol−1 l−1. The optimized sensor shows a good selectivity, satisfactory long-term stability and reproducibility towards DA and a separation of peak potential of 142 mV with uric acid. In addition, the prepared sensor provides favorable recovery in human serum and artificial cerebrospinal solution (aSCF), indicating great potentials in electrochemical detection and biological sensing applications.

In this work, nitrogen-doped carbon with hierarchical porous and hollow sphere structure has been synthesized through a simple and facile route of spray drying using glycine as the nitrogen-containing carbon source. After KOH activation, the prepared material (NHPCA) shows a large specific surface area of 962 m2 g−1 with moderate N-doping of 5.74% and exhibits a high specific capacitance of 271 F g−1 in 6 M KOH electrolyte at 1.0 A g−1, remarkable rate capability and particularly stable cycling performance with no significant specific capacitance drop after 10000 cycles at 1.0 A g−1. The excellent electrochemical properties come from the unique structure and the doping of nitrogen. The hierarchical pore structure improves the efficiency of electrolyte ions transport, and diffusion and the hollow sphere structure further facilitates mass transport. The doping of nitrogen increases the total capacitance by providing redox pseudo-capacitance. The results indicate the as-prepared nitrogen-doped carbon with hierarchical porous and hollow sphere structure can be used as a hopeful candidate for an efficient electrode of commercial supercapacitors devices.

Despite successful commercialization of graphite in lithium ion batteries (LIBs), it is still necessary to develop cost-efficient carbon materials with high capacity and rate capability. Here we report a nitrogen-rich (17.72 at%), hierarchically porous carbon (NHPC) produced by low-cost and large-scale synthetic method through spray granulation followed by pyrolysis under flowing NH3. The synthetic approach featuring using low-cost raw materials (glycine as carbon/nitrogen source and NaCl as template) and industrial spray granulation shows promising application in commercial practice. Benefitting from the rich nitrogen doping and homogeneously porous structure, the NHPC delivers a reversible capacity as high as 1276.5 mA h g−1 at current density of 100 mA g−1 when used as anode for LIB. After 200 cycles at current density of 500 mA g−1, a reversible capacity of 930.6 mA h g−1 remains without any capacity fading compared to the second cycle, showing good electrochemical performance. Even at higher current density of 2 A g−1, a reversible capacity of 582.6 mA h g−1 is achieved, highlighting the superior rate capability compared with most reported carbon-based materials. The mechanism of lithium storage in NHPC is studied in depth by kinetic analysis to figure out the reason for the achieved much higher capacities and rate capability than the theoretical capacity (372 mA h g−1, by forming LiC6) and most reported ones. It is found that there exists considerable capacitive charge storage owing to the adsorbed lithium on the surface of carbon in NHPC, which resulted in the superior rate capability and cycling stability. Besides the adsorbed lithium (capacitive charge storage) and inserted lithium (by forming LiC6 or LiC6@Li4C3N4), deposited lithium in micropores is also found to contribute to achieving the high lithium storage of NHPC.

Autophagy is an evolutionary conserved self-balancing process that plays an important role in maintaining cellular homeostasis via the clearance of damaged organelles and misfolded proteins. Infection-triggered autophagy specifically inhibits the invasion of intracellular bacterial replication and hence protects the cells from microbial infections. It has been reported that Acinetobacter baumannii trigger cell autophagy. However, the role of its virulence protein OmpA remains unclear. Therefore, this study aimed to explore the effects of Acinetobacter baumannii OmpA on cell autophagy and its underlying molecular mechanisms. The results showed that OmpA induced autophagy in HeLa and RAW264.7 cells, increased LC3BII expression, and hindered p62 degradation. Moreover, OmpA triggered incomplete autophagy by interfering the fusion of autophagosomes with lysosomes. Besides, OmpA activated MAPK/JNK signaling pathway and enhanced the phosphorylation levels of JNK, p38, and ERK, c-Jun. Inhibition of JNK signaling pathway suppressed OmpA-induced autophagy in HeLa cells. Ab wild-type strains carrying OmpA triggered incomplete autophagy and resulted in a large number of IL-1β production. Ab-△OmpA strain (OmpA gene mutation) restored autophagic flux and reduced the accumulation of p62 and the release of IL-1β in HeLa cells. Rapamycin activated autophagy to inhibit OmpA-induced IL-1β secretion and protect HeLa cells from inflammatory damage. Collectively, these results suggest that OmpA can induce autophagy in HeLa cells through MAPK/JNK signaling pathway. Pre-treatment with Rapamycin activates autophagy and protects against cell death.

Transition-metal sulfides (TMSs) powered by conversion and/or alloying reactions are considered to be promising anode materials for advanced lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs). However, the limited electronic conductivity and large volume expansion severely hinder their practical application. Herein, we report a covalent coupling strategy for TMS-based anode materials using amide linkages to bind TMSs and carbon nanotubes (CNTs). In the synthesis, the thiourea acts as not only the capping agent for morphology control but also the linking agent for the covalent coupling. As a proof of concept, the covalently coupled ZnS/CNT composite (CC-ZnS/CNT) has been prepared, with ZnS nanoparticles (∼10 nm) tightly anchored on CNT bundles. The compact ZnS-CNT heterojunctions are greatly beneficial to facilitating the electron/ion transfer and ensuring structural stability. Due to the strong coupling interaction between ZnS and CNTs, the composite presents prominent pseudocapacitive behavior and highly reversible electrochemical processes, thus leading to superior long-term stability and excellent rate capability, delivering reversible capacities of 333 mAh g-1 at 2 A g-1 over 4000 cycles for LIBs and 314 mAh g-1 at 5 A g-1 after 500 cycles for SIBs. Consequently, CC-ZnS/CNT exhibits great competence for applications in LIBs and SIBs, and the covalent coupling strategy is proposed as a promising approach for designing high-performance anode materials.

We investigate the phenomenon of stochastic bursting in a noisy excitable unit with multiple weak delay feedbacks, by virtue of a directed tree lattice model. We find statistical properties of the appearing sequence of spikes and expressions for the power spectral density. This simple model is extended to a network of three units with delayed coupling of a star type. We find the power spectral density of each unit and the cross-spectral density between any two units. The basic assumptions behind the analytical approach are the separation of timescales, allowing for a description of the spike train as a point process, and weakness of coupling, allowing for a representation of the action of overlapped spikes via the sum of the one-spike excitation probabilities.

We investigate the transition from incoherence to global collective motion in a three-dimensional swarming model of agents with helical trajectories, subject to noise and global coupling. Without noise this model was recently proposed as a generalization of the Kuramoto model and it was found that alignment of the velocities occurs discontinuously for arbitrarily small attractive coupling. Adding noise to the system resolves this singular limit and leads to a continuous transition, either to a directed collective motion or to center-of-mass rotations., 3 figures

Carbon-based anode materials hold a promising future for sodium-ion batteries (SIBs) due to their natural abundance and low cost of development. In spite of carbon's important role in the commercialization of lithium-ion batteries (LIBs), further exploration is necessary in order to find high-performance, high-rate carbon anode materials for SIBs. A honeycomb-like, nitrogen-rich (17.72 at%), hierarchically porous, and highly disordered carbonaceous material (N-HC) with an expanded interlayer distance (0.44 nm in average) is synthesized by spray drying and subsequent pyrolysis under flowing NH3. The hierarchically porous structure and rich nitrogen doping result in a large specific surface area (722 m2 g−1), more defects and active sites, and greater functional interface accessibility for the active porous carbonaceous material and electrolyte. When N-HC is used as the anode material for SIBs, the batteries display favorable discharge capacities (255.9 mA h g−1 in the 3000th cycle at 500 mA g−1) and good capacitive-energy-storage behavior (67% at a scan rate of 0.5 mV s−1) with excellent high-rate performance and ultra-stable cyclability over 10,000 cycles at 5000 mA g−1. Our results show that the combination of the hierarchically porous structure and nitrogen doping leads to improved energy storage by increasing the capacitive energy storage, which enhances the high-rate performance of N-HC. To further enhance the performance of the material, an electrical pretreatment is employed to increase the initial Coulombic efficiency of N-HC to 79.5%, a record high for an SIB cell. A full cell with an N-HC anode and a Na3V2(PO4)3/C cathode shows a high capacity with a favorable cyclability (238.7 mA h g−1 after 100 cycles at 100 mA g−1 and a capacity retention of 95.3% compared to the second cycle).

The ether model molecules BPE (phenylbenzyl ether), diphenyl ether (DPE) and phenoxyethylbenzene (PPE) of lignin were used as degradation raw materials, and Pd-Al2O3 was used as catalyst to react in batch reactor and continuous reactor, respectively. Pd-Al2O3 showed good degradation performance in batch reaction. The catalytic performance of three substances was compared in a flow reactor. The reasons of catalyst deactivation and the products adsorbed on the surface during the hydrogenolysis of BPE were studied.

A mesoporous graphitic carbon-encapsulated Fe2 O3 nanocomposite is synthesized as a superior anode material for sodium-ion batteries. A threefold strategy is adopted to achieve a high rate performance. First, the mesoporous structure with high specific surface area and large pore volume facilitates the transfer of electrolyte and accommodates the large volume change. Secondly, graphitic carbon encapsulation further improves the electronic conductivity of the nanocomposite. Finally, ultrafine Fe2 O3 nanocrystals effectively shorten the Na+ diffusion length. Consequently, this nanocomposite exhibits stable and fast Na+ storage, thus leading to excellent rate capability and cyclability. Pseudocapacitive behavior is found to dominate in the redox reactions, accounting for the outstanding rate and cycling performance. In addition, full cells, assembled with O3-Na0.9 [Cu0.22 Fe0.30 Mn0.48 ]O2 as cathodes, present good electrochemical performance.

Various strategies have been developed to improve the conversion for the Baeyer-Villiger oxidation. However, the catalytic effects of the Baeyer-Villiger oxidation for the mixed ketones are rarely reported, though it is also important for the natural and industrial separation processes. In this report, magnetite Cu modified Fe3O4 supported mesoporous silica microspheres (Cu-Fe3O4@mSiO2) have been successfully synthesized by two step direct hydrothermal method (DHT). Over 99% of cyclohexanone conversion was obtained with mild air oxidation and benzaldehyde as sacrificing agent over Cu-Fe3O4@mSiO2. The catalytic system also shows higher conversion rates for small molecular ketones in the mixed ketone reactants, which was attributed to the enhanced mass transfer effect and Fe-Cu composite active sites in the magnetite mesoporous silica microspheres. The catalyst could be recycled for four times with similar catalytic performance, which shows enhanced shape selectivity in aerobic Baeyer-Villiger oxidations for mixed cyclic ketones.

SnS2 /graphene composites have attracted extensive attention in energy storage owing to their excellent electrochemical performance. However, most of the previous methods to synthesize SnS2 /graphene composites require long times, high temperatures, or high pressures, which are obstacles for practical low-cost production. A simple one-pot strategy to prepare SnS2 /graphene composites has been developed, which is not time-consuming (1 h) and requires moderate temperature (75 °C) in atmosphere. Through this method, ultrafine SnS2 nanoparticles anchored on graphene nanosheets are prepared and exhibit excellent electrochemical performance for both lithium and sodium storage. Specifically, as anodes for lithium-ion batteries, the SnS2 /graphene electrode delivers a high capacity of 1480 mAh g-1 after 50 cycles at 0.2 A g-1 . Even at 10 A g-1 , the SnS2 /graphene electrode can achieve a capacity of 666 mAh g-1 . A constructed full lithium-ion cell exhibits a capacity of 957 mAh g-1 after 50 cycles at 1 A g-1 . This simple one-pot strategy may pave the way for large-scale production and practical application of SnS2 /graphene composites in energy storage.

We report a simple one-pot solvothermal method of a FeS2/CNT (carbon nanotube) neural network nanostructure composite (FeS2/CNT-NN) that exhibits outstanding electrochemical performance as a sodium-ion battery anode. In these composites, uniform microspheres assembled from FeS2 nanoparticles act as “somas” and CNTs act as “neurites”. The weight ratio of FeS2 to CNTs affects not only the composite morphology, but also the sodium-ion storage performance. By optimizing this ratio, we achieve stable capacities up to 394 mA h g−1 after 400 cycles at 200 mA g−1. Most impressively, when the current densities are increased, excellent capacity and stability are maintained. At 1 A g−1 to 22 A g−1, surprisingly high capacities of 309 mA h g−1 to 254 mA h g−1 are maintained after 1800 cycles and 8400 cycles, respectively. The excellent electrochemical performance has been found to originate from the unique neural network structure, which offers high surface area and small FeS2 particle size for sufficient sodiation and desodiation, and enough room and mechanical integrity for volume expansion. Pseudocapacitance has also been found to dominate in the redox reactions, accounting for the outstanding rate and cycling performance. The excellent charge-discharge performance shows that FeS2/CNT-NN composites are promising candidates for rechargeable sodium-ion batteries.

SnO 2 has triggered lots of research efforts as anode for sodium-ion batteries. However, the volume expansion and poor conductivity lead to an unsatisfactory electrochemical performance for the practical application of SnO 2 . In this work, a novel carbon-coated SnO 2 supported by porous carbon sphere composite is synthesized by hydrothermal process combining with annealing method. The porous carbon sphere@SnO 2 @carbon layer coating composite anode delivers a reversible capacity of 326 mAh g −1 over 80 cycles at a current density of 50 mA g −1 . Even at 1600 mA g −1 , a capacity of 82 mAh g −1 is still maintained after 550 cycles. Such excellent performance can be ascribed to the unique structure, which efficiently accommodates volume expansion, enhances conductivity and offers shortened sodium-ion transport pathway. The charge-storage mechanisms can be comprised of diffusion-controlled reaction and pseudocapacitance effect. At high scan rate of 1.0 mV s −1 , the capacity contribution of pseudocapacitance effect could reach as high as 78%.

EPR steering is a kind of quantum correlation that is intermediate between entanglement and Bell nonlocality. In this paper, by recalling the definitions of unsteerability and steerability, some properties of them are given, e.g, it is proved that a local quantum channel transforms every unsteerable state into an unsteerable state. Second, a way of quantifying quantum steering, which we called the generalized steering robustness (GSR), is introduced and some interesting properties are established, including: (1) GSR of a state vanishes if and only if the state is unsteerable; (2) a local quantum channel does not increase GSR of any state; (3) GSR is invariant under each local unitary operation; (4) as a function on the state space, GSR is convex and lower-semi continuous. Lastly, by using the majorization between the reduced states of two pure states, GSR of the two pure states are compared, and it is proved that every maximally entangled state has the maximal GSR.

SnS nanoparticles/CNTs composite (SnS/CNTs composite) is synthesized by a facile one-pot solvothermal reaction. The structural characterizations reveal pure SnS nanoparticles with the size of less than 10 nm distribute on the surface of CNTs with the diameter of less than 20 nm. The SnS/CNTs composite electrode performs high reversible capacity and good cyclability (365 mAh/g at 50 mA/g after 50 cycles), which is superior to that of pure SnS electrode synthesized without the adding of CNTs (115.9 mAh/g at 50 mA/g after 50 mA/g cycles). Even increasing the current density to 500 mA/g, the SnS/CNTs composite electrode still delivers a reversible capacity up to 210 mAh/g after 100 cycles, nearly two times higher than that of the pure SnS electrode (108 mAh/g after 100 cycles). The rate performance of the SnS/CNTs composite electrode is also better than that of pure SnS electrode at different current densities from 50 mA/g to 800 mA/g. The enhanced electrochemical performance of SnS/CNTs composite can be attributed to the adding of CNTs as a flexible and conductive structure supporter and the formation of SnS nanoparticles with small size. The SnS nanoparticles/CNTs composite structure not only benefits for buffering the volume change during charge and discharge process, but also increases the surface area for sufficient electrode-electrolyte contacting, and shortens Na+ diffusion length, which improves the conductivity and stability of active material and finally provides desirable electrochemical performance.

Sodium-ion batteries have attracted worldwide attention as potential alternatives for large scale stationary energy storage due to the rich reserves and low cost of sodium resources. However, the practical application of sodium-ion batteries is restricted by unsatisfying capacity and poor rate capability. Herein, a novel mechanism of improving both interfacial and surface charge transfer is proposed by fabricating a graphene oxide/SnO2/Co3O4 nanocomposite through a simple hydrothermal method. The formation of heterostructures between ultrafine SnO2 and Co3O4 could enhance the charge transfer of interfaces owing to the internal electric field. The pseudocapacitive effect, which is led by the high specific area and the existence of ultrafine nanoparticles, takes on a feature of fast faradaic surface charge-transfer. Benefiting from the synergistic advantages of the heterostructures and the pseudocapacitive effect, the as-prepared graphene oxide/SnO2/Co3O4 anode achieved a high reversible capacity of 461 mA h g-1 after 80 cycles at a current density of 0.1 A g-1. Additionally, at a high current density of 1 A g-1, a high reversible capacity of 241 mA h g-1 after 500 cycles is obtained. A full cell coupled by the as-prepared graphene oxide/SnO2/Co3O4 anode and the Na3V2(PO4)3 cathode was also constructed, which exhibited a reversible capacity of 310.3 mA h g-1 after 100 cycles at a current density of 1 A g-1. This method of improving both interfacial and surface charge transfer may pave the way for the development of high performance sodium-ion batteries.

In this report, heterogeneous Fenton-like degradation activities of ofloxacin (OFL) were investigated with synergistic degradation effects of bimetallic Fe-Cu on ordered mesoporous silicon (Fe-Cu@MPSi). With the characterization such as XRD, TEM, SEM and N 2 sorption-desorption isotherms, Fe-Cu@MPSi showed ordered mesoporous structure, high BET surface area, uniform mesopore size (∼2.4 nm) and moderate pore volume (0.19 cm 3 /g). The Fe 2 O 3 and CuO nanoparticles highly dispersed in the mesopore channels and the surface of the catalyst. Owing to the enhanced mass and electron transfer properties of mesoporous silicon, the synergetic interfacial effect of Fe and Cu on the surface of the catalyst and the complexation of OFL and Cu 2+ , the Fe-Cu@MPSi heterogeneous Fenton-like catalyst showed exclusive and high degradation activities for OFL. The degradation mechanism of Fe-Cu@MPSi was also investigated with the optimal oxidation conditions of 30 mg/L OFL, 1 g/L catalyst, 2000 mg/L H 2 O 2 and initial pH.