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Lithium-sulfur (Li-S) batteries are promising candidates for next-generation energy storage. However, the notorious lithium polysulfides (LiPSs) shuttle effect and torpid redox kinetics hinder their practical application. Enhancing phase conversion efficiency and limiting the dissolution of LiPSs are critical for stabilizing Li-S batteries. Herein, sulfiphilic defective TiO

This special issue contains a selection of articles on globalization and fintech. The contributions provide new insights on reform of the international economic order, paying special attention to uncertainty and economic policy coordination. They will certainly help improve our understanding of these topics.

It is highly desirable to develop high-efficiency non-precious electrocatalysts toward oxygen reduction reaction (ORR). In this work, Fe2O3-encapsulated and Fe-Nx-containing porous carbon spheres (Fe2O3/N-MCCS) with unique multi-cage structures and high specific surface area (1360 m2 g−1) are fabricated. The unique porous structure of Fe2O3/N-MCCS ensures fast transportation of oxygen during ORR. The combined effect of Fe2O3 nanoparticles and Fe-Nx configurations endows Fe2O3/N-MCCS (E1/2 = 0.837 V vs. RHE) with superior ORR activity and methanol tolerance to Pt/C. And, Fe2O3/N-MCCS exhibits better stability than nitrogen-modified carbon. The characterization results of Fe2O3/N-MCCS after long-term test reveals its excellent structural stability. Impressively, zinc-air battery based on Fe2O3/N-MCCS showed a peak power density of 132.4 mW cm−2 and a specific capacity of 797 mAh g−1, respectively.

As emerging energy storage systems, lithium-sulfur (Li–S) batteries have engaged extensive attention owing to the ideal energy density. The bottleneck of achieving the practical application on Li–S batteries is the shuttle effects of lithium polysulfide (LiPS) and the sluggish electrochemical conversion kinetics. Here, a flexible SnS2-hollow carbon nanofibers (SnS2@HCNF) membrane is designed as an interlayer to catalyze the conversion of LiPS. Hollow carbon nanofibers (HCNF) provide an electron passageway to accelerate the redox reaction of LiPS, while SnS2 achieves rapid Li ions transport and an efficient catalytic route, promoting the decomposition of Li2S. Owing to the synergistic effect of HCNF and SnS2, the SnS2@HCNF endow the Li–S batteries with high rate performance (694 mAh g−1 at 3C) and low capacity fading rate (0.056 % per cycle during 500 cycles at 1C). The material and design strategy manifested in this work can pave a new way towards developing shuttle suppression interlayers.

This paper analyzes the optimal regulation for “Too Big to Fail” (TBTF) in a simple model. As the government cannot credibly commit to no bail-out during crises, banks have an incentive to become excessively large ex-ante. In this case, no single policy can fully eliminate the inefficiencies from TBTF. The optimal regulation for the first-best allocation features a capital requirement and an issuance of Contingent Convertible Bonds (CoCos) where the former addresses the moral hazard issue from government bailouts and the latter improves risk-sharing. Moreover, a combination of the capital requirement and size regulation can implement a second-best allocation where the government has to bail out the banking sector but the social cost of bail-out is internalized by the banks. In this case, the capital requirement forces banks to internalize the bailout cost while the size regulation directly discourages banks to become large.

Metal organic frameworks (MOFs) derived carbonaceous materials have a wide range of applications in the fields of energy storage, catalysis, adsorption and separation, etc. Especially, zeolitic imidazolate framework-8 (ZIF-8) is an excellent candidate to synthesize porous carbon due to the large surface area and high nitrogen content. However, the dominated microporous structure of ZIF-8-derived carbon significantly hinders ionic mass transfer, limiting the improvement of performance. Herein, MOF-derived mesoporous carbon was prepared using ZIF-8 as carbon precursor and cheap sodium silicate (Na2SiO3) as activator. The introduction of Na2SiO3 created rich mesoporous structure and increased specific surface area, as well as the effects of pyrolysis temperature and Na2SiO3 dosage on performance was also investigated. The obtained ZIF-derived porous carbon exhibits good electrochemical performance with specific capacitance of 263 F/g at 1 A/g and excellent cycle life (96.07% after 10,000 GCD cycles) in supercapacitor. The use of cheap Na2SiO3 activator provides a new orientation for the preparation of MOF-derived carbons with rich pores, high surface area, and facilitates the large-scale application of MOF-derived carbons.

Figs and fig pollinators are one of the few classic textbook examples of obligate pollination mutualism. The specific dependence of fig pollinators on the relatively safe living environment with sufficient food sources in the enclosed fig syconia implies that they are vulnerable to habitat changes. However, there is still no extensive genomic evidence to reveal the evolutionary footprint of this long-term mutually beneficial symbiosis in fig pollinators. In fig syconia, there are also non-pollinator species. The non-pollinator species differ in their evolutionary and life histories from pollinators. We conducted comparative analyses on 11 newly sequenced fig wasp genomes and one previously published genome. The pollinators colonized the figs approximately 66.9 million years ago, consistent with the origin of host figs. Compared with non-pollinators, many more genes in pollinators were subject to relaxed selection. Seven genes were absent in pollinators in response to environmental stress and immune activation. Pollinators had more streamlined gene repertoires in the innate immune system, chemosensory toolbox, and detoxification system. Our results provide genomic evidence for the differentiation between pollinators and nonpollinators. The data suggest that owing to the long-term adaptation to the fig, some genes related to functions no longer required are absent in pollinators.

In this study, a new composite electrode of palladium (Pd) nanoparticles dispersed on polypyrrole-reduced graphene oxide (PPy-rGO) loaded on foam-nickel was achieved by galvanostatic method. Characterization of structures, morphology and crystallinity of the synthesized materials were investigated by scanning electron microscopes (SEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Raman spectroscopy and electrochemical impedance spectroscopy (EIS). The results of XPS and XRD demonstrated Pd showed primarily as Pd0. From SEM and TEM results, we had seen that Pd nanoparticles were dispersible well on the composite electrode. Raman spectroscopy was used to show the state of graphene oxide and further demonstrated that PPy and rGO had existed of on the foam Ni matrix. The data of EIS also suggested the charge transfer of the new composite electrode decreased compared to Pd/PPy/foam-Ni and PPy/foam-Ni composite electrodes. The effect of the electropolymerization potential on Pd/PPy-rGO/foam-Ni electrode for removing triclosan (TCS) was examined. It was found that the removal efficiency of TCS on the composite electrode could reach 100% at electropolymerization potential of 0.7 V and reaction time of 100 min. Keywords: Pd/PPy-rGO/foam-Ni electrode, Triclosan, Electrocatalytic hydrodechlorination, Potentiostatic electropolymerization, Applied potential

Over the past two decades, emerging market economies have improved their external liability structures by increasing the share of debt denominated in local currencies, while foreign currency debt is considered a major source of financial instability. This paper embeds the debt denomination choice in a sudden stop model and explore its implications for the optimal capital control policy. As its payoff depends on the real exchange rate, the local currency debt provides better risk-sharing for emerging market economies but introduces additional distortions. Compared to the competitive equilibrium, a discretionary planner has incentives to deflate the debt burden denominated in local currencies, which increases its issuance cost ex ante. In contrast, a social planner with commitment would promise a higher future payment to obtain a more favorable local currency bond price. Quantitatively, the optimal policy under commitment encourages more borrowing in local currencies, mitigates the severity of crises, and improves welfare relative to the laissez-faire.

Multi-element doped mesoporous carbon materials are considered as one of the most promising electrode materials for supercapacitors due to their large specific surface area, abundant mesoporous structure, heteroatom doping and good conductivity. Herein, the N, O co-doped ordered mesoporous carbon (N/O-OMC) were successfully prepared by the solid-solid grinding method using KIT-6 as template, Fe(NO3)3 as catalyst, and polyvinylpyrrolidone (PVP) as source of C, N, and O. The effect of PVP amount on the structural parameters of the sample was also discussed. The resulting N/O-OMC replicated the morphology of KIT-6 and showed suitable N and O doping, a large specific surface area and an ordered dual-mesoporous structure. As the electrode materials, N/O-OMC exhibit excellent specific capacitance of 229 F g−1 at 1 A g−1, excellent rate performance (79.5%) and cycle stability (92.3% after 5000 cycles). This multi-element doped mesoporous carbon material was proved a good candidate for high-performance electrode materials.

The cerebellum receives sensory inputs from mossy fiber-granule cell or climbing fiber pathways, and generates motor-related outputs. However, the temporal and special mechanism of the sensory information processing in cerebellar cortex is still unclear. Therefore, we here investigated the temporal-spacial mechanism between the facial stimulation-evoked field potential responses in granular layer (GL) and molecular layer (ML), by duo-electrophysiological recording technique and pharmacological methods in urethane-anesthetized mice. Our results showed that air-puff stimulation of ipsilateral whisker pad evoked successively field potential responses in GL and ML. The field potential response in GL exhibited a strong excitatory component (N1) followed by an inhibitory component (P1), while the field potential response in ML exhibited a tiny excitatory component (N1) followed by strong inhibitory component (P1). The latency of N1 was decreased with the increase of recording depth in ML, and it was the shortest in GL. Notably, the latencies of P1 in GL and ML were similar regardless the relative recording sites. Furthermore, blocking α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor-mediated parallel fiber excitatory inputs by application of AMPA receptor antagonist, NBQX prevented P1 in both ML and GL. Moreover, application of GABAA receptors antagonist, gabazine simultaneously abolished P1 in both ML and GL. These results indicate that the facial stimulation evoked a simultaneous GABAergic inhibition in both ML and GL via mossy fiber-GC-parallel fiber pathway, suggesting that the sensory stimulation simultaneously evoked excitation of molecular layer interneurons (MLIs) and GL Golgi cells in cerebellar cortex.

We propose a new housing portfolio channel through which QE affects output. In response to QE, intermediaries rebalance portfolios from bonds to houses, lowering the return to saving and stimulating consumption and output. We study this channel empirically in a German housing boom without credit boom. Identification exploits regional variation in land scarcity to measure exposure. Our channel accounts for 60-80% of the total QE impact, with the term spread, the credit, collateral and wealth channels accounting for the remainder. To illustrate our channel, we also set up a simple portfolio model with preferred habitat investing in local housing markets.

Standard models of capital flows to emerging market economies focus on debt flows and a pecuniary externality. However, by offering better risk sharing, international equity flows can render such externality unimportant, yet many economies fail to attract equity investment in a large quantity. We propose a theory of endogenous composition of capital flows that highlights two asymmetries. In our model, poor institutional quality leads to an inefficiently low share of equity financing as well as an inefficiently high volume of total inflows. Somewhat surprisingly, a social planner would often impose taxes on both equity and debt inflows. Our story differs in important ways from an alternative narrative focusing on collateral constraint.

We document the effect on Chinese firms of the Shanghai (Shenzhen)-Hong Kong Stock Connect. The Connect was an important capital account liberalization introduced in the mid-2010s. It created a channel for cross-border equity investments into a selected set of Chinese stocks while China's overall capital controls policy remained in place. Using a difference-in-difference approach, and with careful attention to sample selection issues, we find that mainland Chinese firm-level investment is negatively affected by contractionary U.S. monetary policy shocks and that firms in the Connect are more adversely affected than those outside of it. These effects are economically large, robust, and stronger for firms whose stock return has a higher covariance with the world market return. We also find that firms in the Connect enjoy lower financing costs, invest more, and have higher profitability than unconnected firms. We discuss the implications of our results for the debate on capital controls and independence of Chinese monetary policy. \

Mesoporous ribbon-shaped graphitic carbon nanofibers (MRCNFs) have been prepared by combination of electrospinning technique, template method and catalytic graphitization of transition metal. Transition metal Co, originated from Co(NO3)2·6H2O doped in spinning solution, serves as both template of mesopores and catalyst for graphitic structure. The microstructure of MRCNFs has been optimized by adjusting doping amount of Co(NO3)2·6H2O. The resultant MRCNFs present a relatively centralized distribution of 2–10 nm mesopores, modest specific surface area of 463 m2 g−1 and pore volume of 0.575 cm3 g−1. In addition, considerable nitrogen- and oxygen-containing functionalities (2.88 at.% of N and 4.88 at.% of O) are detected on MRCNFs. In view of electrode materials for supercapacitors, as-obtained ribbon-shaped morphology, mesoporous structure, considerable surface heteroatom-containing functionalities and high graphitization degree synergistically enhance the electrolyte ion diffusion and electron conduction. In a three-electrode test system, the resultant MRCNFs electrodes exhibit high specific capacitance (228 F g−1 at 0.2 A g−1), rate capability (of 58% capacitance retention at 20A g−1) and excellent cycle stability(of 95% capacitance retention after 5000 cycles at 2 A g−1).

Variable optical attenuation and optical modulation are essential operations in integrated photonic circuits. A new graphene plasmonic gap waveguide structure, which possesses the functions of variable optical attenuator and modulator, is proposed and numerically investigated. The propagation and attenuation modes of the structure can be realized by tuning the gate-voltage. The result shows that it can achieve great modulation depth per micrometer and the working frequency range of 8 THz or more for the variable optical attenuator and the modulator. It also has the advantages of high tolerance, large attenuation range/ modulation depth, wide bandwidth and high integration without crosstalk, which would be promising for high integrated optical circuits.

Lignin, a renewable resource, has been used as carbon precursor to prepare porous carbon nanofiber films by electrospinning with PVP as spinning agent and Mg(NO3)2·6H2O as additive. The effect of the content of Mg(NO3)2·6H2O on the morphology, microstructure, surface chemistry, specific surface area and porous structure of the lignin-based porous carbon nanofiber films (LCNFs) is investigated. Results show that with the increase of the content of Mg(NO3)2·6H2O in the spinning solution, the average diameter of fibers is decreased obviously, while specific surface area and mesoporosity are increased significantly. When mass ratio of Mg(NO3)2·6H2O/lignin is 2:1, the resultant LCNFs possessed an increased specific surface area of 1140 m2 g−1 and a significantly improved mesoporosity of 78%, and showed hierarchical porous structure. LCNFs were cut into electrode for supercapacitors directly and were evaluated in three-electrode and two-electrode cell. With increase of Mg(NO3)2·6H2O, the capacitive performance of LCNFs turn better. When mass ratio of Mg(NO3)2·6H2O/lignin was 2:1, the specific capacitance of LCNFs reached 248 F g−1 at 0.2 A g−1, much higher than that of sample without Mg(NO3)2·6H2O (173 F g−1). Moreover, LCNFs showed an outstanding rate performance (capacitance retention of 59–67% from 0.2 to 20 A g−1) and a good cycling stability (capacitance retention of 97% after 1000 cycles at 20 A g−1).

On the basis of the synthesized equal-sized mono-spheres (~ 180 nm), the luminescence properties of Y2O3:0.2 mol%Bi,2xmol%Eu (x = 0.1–7) phosphors were investigated in detail. The PL spectra of Y2O3:Bi,Eu mono-spheres displays both the bluish green/blue emission of Bi3+ at 501/410 nm (3P1-1S0, Bi3+ in C2 or S6 sites) and the red emission of Eu3+ at 612 nm (5D0–7F2) upon 330/375 nm excitation. Increasing the doping concentration of Eu3+ ions in the phosphor mono-spheres significantly enhances Eu3+ emission (5D0–7F2) and reduces Bi3+ emission (3P1-1S0) due to the effective energy transfer from Bi3+ to Eu3+ ions. At the optimal Eu3+ concentration of 3 mol%, the Y2O3:Bi,Eu mono-spheres show an intense red emission and a high external quantum efficiency of 42.8%. The energy transfer (ET) process from Bi3+ to Eu3+ ions is determined to be a resonant type via dipole-quadrupole interaction with an ET efficiency of 86.3%. By varying the Eu3+ concentration, the luminescence color can be tuned from bluish green to nearly white and eventually to orange red under 330 nm excitation (Bi3+ in C2 sites), and also can be tuned from blue to pink and then to orange red under 375 nm excitation (Bi3+ in S6 sites). Temperature-dependent luminescence spectra demonstrated the good thermal stability of the obtained phosphor mono-spheres.

Graphene metasurface has attracted a lot of attentions due to the unique tunability for exotic electromagnetic properties. In this work, we propose and numerically investigate a tunable metasurface with two non-coplanar and inter-perpendicular graphene nanoribbon arrays. The variation of transmission at different substrate thickness and the coupled mode are analyzed. It is shown that the Rabi-like splitting can be achieved by the coupling between localized and delocalized graphene surface plasmon polaritons. Tunable coupling strength and positions with different gate-voltages have been discussed. The effect of relaxation time and oblique incidences to resonant responses are also investigated. Additionally, we find an optical analogue of a spring, where the spectral dip vibrates around its equilibrium position at a certain wavelength. Our study suggests that the proposed structure is potentially attractive for realization of tunable double-channel filter, optical switch, and variable optical attenuator based on the graphene metasurface.

Lignosulfonates are a by-product of the agricultural and forestry waste and paper industries. Strengthening the sustainable use of lignosulfonates is a problem to be solved. In this study, hydrophilic agricultural and forestry waste calcium lignosulfonate (CaLS) was combined with single/double-layered MXene, and added to the natural polysaccharide sodium alginate (SA) to prepare a pervaporation me, membrane with a three-component hybrid structure. Characterization experiments such as scanning electron microscopy and contact angle demonstrated that CaLS increased the hydrophilicity and reduced swelling of the membrane, and MXene formed a layered cross-sectional morphology that further reduced swelling. A 90% ethanol aqueous solution was used to evaluate the dehydration performance of the membrane. The results showed that the permeation flux and separation factor of the membrane increased by 74% and 160%, respectively. Compared to the pure SA membrane after CaLS was incorporated. MXene further improved the pervaporation performance of the MXene@CaLS/SA membrane, with the permeation flux of about 938 g·m−2·h−1, and the separation factor of 4612 (two and four times higher than the pure SA membrane, respectively). This study provides a theoretical and technical basis for the development of new separation materials, and will help expand the high-value utilization of lignosulfonates.

The serious volume expansion and agglomeration of tin dioxide (SnO2) during the long-term charging/discharging process are the main obstacles that limit its application in lithium-ion batteries (LIBs). However, even if it is composited with carbon materials, achieving flexibility and free-standing by a simple preparation method is still a challenge. Herein, a composite electrode-membrane in which SnO2 nanoparticles are in situ and uniformly filled in the interpenetrating network porous structure of electrode-membrane has been successfully prepared. Due to the encapsulating of the membrane porous structure, the volume expansion of SnO2 is greatly alleviated that exhibits enhanced lithium storage performance. When used as free-standing anodes, the highest reversible capacity of 659.1 mA h g−1 can be obtained at 50 mA g−1. And the prepared sample possesses excellent rate capacity and competitive cycling performance without obvious agglomeration and pulverization in the structure of SnO2 nanoparticles and composite electrode-membrane after 200 cycles, exhibiting excellent reversibility and structural integrity. In summary, this paper demonstrates that the synergistic effect of membrane technology and SnO2 nanoparticles can effectively enhance the lithium storage performance of C/SnO2 composites and provides a simple idea for preparing carbon/metal oxide composite materials with alleviating the volume expansion of metal oxides.

Carbon-encapsulation is an effective strategy to inhibit the volume expansion and enhance the cycle stability of silicon anode in the lithium-ion battery. However, it is still a big challenge to prepare carbon/silicon composite materials with excellent flexibility using a simple and high-efficient method. Herein, a flexible carbon-based composite membrane embedded with nano-silicon particles and graphene is successfully developed via simple precursor preparation and carbonization processes. The obtained carbon-based composite membrane possesses a porous 3D network structure, which can provide buffer space to alleviate the volume expansion of nano-silicon. Due to the unique architecture, the carbon-based composite membrane presents a high reversible capacity of 1135.7 mA h g−1 and an effective utilization rate of nano-silicon up to 92.6%. After 100 cycles, the reversible capacity is still maintained at 897.6 mA h g−1 with a capacity retention rate of 74.2%. Furthermore, after 100 cycles, almost no capacity loss is detected, and the Coulombic efficiency is close to 100%, demonstrating excellent reversibility and robust stability. In summary, this research provides a simple and high-efficiency strategy for the preparation of flexible carbon/silicon composite anodes for lithium-ion batteries.

Digital image correlation (DIC) is one of the most used techniques for measuring deformation. It is widely used in mechanical performance testing, structural health monitoring and many other fields. The standard subset based DIC technology assumes that the deformation is continuous. However, discontinuous deformation such as cracks and dislocations are quite common in practical applications. The measurement accuracy of DIC in these areas will be significantly reduced, or even measurement failure. This is a limitation for the application of DIC. To overcome this problem, this paper proposes a variable subset DIC algorithm. Taking the zero-mean normalized cross-correlation (ZNCC) function as the correlation criterion, the concept of pixel-level ZNCC value distribution map is proposed. The proposed algorithm can automatically select the most suitable subset for matching under the guidance of the pixel-level ZNCC value distribution map. This method has the advantages of good flexibility, strong applicability, and high precision.

Although several factors affecting porcine circovirus type 2 (PCV2) infection have been reported, their precise roles are far from clear. The aim of this study was to determine whether 17-dimethylaminoethylamino-17-demethoxygeldanamycin (17-DMAG), an inhibitor of Hsp90, could significantly affect PCV2 infection and immune responses in BALB/c mice. Intraperitoneal injection of 17-DMAG significantly reduced viral loads in the blood and tissues of mice infected with PCV2, compared with control groups. The 17-DMAG treatment decreased serum interleukin (IL)-10 and tumor necrosis factor(TNF)-α levels, but it did not have a significant effect on the IL-1β level. These data demonstrate that 17-DMAG is highly effective in suppressing PCV2 replication in BALB/c mice, indicating that it has potential value as an antiviral drug against PCV2 infection.

This paper reviews selected post-Global Financial Crisis theoretical and empirical contributions on capital controls and identifies three theoretical motives for the use of capital controls: pecuniary externalities in models of financial crises, aggregate demand externalities in new-Keynesian models of the business cycle, and terms of trade manipulation in open economy models with pricing power. Pecuniary and demand externalities offer the most compelling case for the adoption of capital controls, but macroprudential policy can also address the same distortions. So capital controls generally are not the only instrument that can do the job. If evaluated through the lenses of the new theories, the empirical evidence reviewed suggests that capital controls can have the intended effects, even though the extant literature is inconclusive as to whether the effects documented amount to a net gain or loss in welfare terms. Terms of trade manipulation also provides a clear cut theoretical case for the use of capital controls, but this motive is less compelling because of the spillover and coordination issues inherent with the use of control on capital flows for this purpose. Perhaps not surprisingly, only a handful of countries have used capital controls in a countercyclical manner, while many adopted macroprudential policies. This suggests that capital control policy might entail additional costs other than increased financing costs, such as signaling the bad quality of future policies, leakages, and spillovers.

Capital flows and real estate are pro-cyclical, and real estate has a substantial weight in economies' income and wealth. In this paper, we study the role of real estate markets in the transmission of bank flow shocks to output growth across German cities. The empirical analysis relies on a new and unique matched data set at the city level and the bank-firm level. To measure bank flow shocks, we show that changes in sovereign spreads of Southern European countries (the so-called GIPS spread) can predict German cross-border bank flows. To achieve identification by geographic variation, in addition to a traditional supply-side variable, we use a novel instrument that exploits a policy assigning refugee immigrants to municipalities on an exogenous basis. We find that output growth responds more to bank flow shocks in cities that are more exposed to tightness in local real estate markets. We estimate that, during the 2009-2014 period, for every 100-basis point increase in the GIPS spread, the most exposed cities grow 15-25 basis points more than the least exposed ones. Moreover, the differential response of commercial property prices can explain most of this growth differential. When we unpack the transmission mechanism by using matched bank-firm-level data on credit, employment, capital expenditure and TFP, we find that firm real estate collateral as measured by tangible fixed assets plays a critical role. In particular, bank flow shocks increase the credit supply to firms and sectors with more real estate collateral. Higher credit supply then leads firms to hire and invest more, without evidence of capital misallocation.

Carbon nanofiber has been one of the promising electrode materials for supercapacitors. It is desirable but still challenging to optimize meso-/micro-pore ratio and configuration while achieving a high specific surface area in carbon nanofibers. Here, we present the design and preparation of carbon nanofiber mats with both high specific surface area and rational meso-/micropore configuration by electrospinning tetraethyl orthosilicate (TEOS)/phenolic resin (PR)/polyvinylpyrrolidone (PVP)/F127 blend solution, followed by carbothermal reduction, removal of carbon and chlorination. Silicon carbide nanofibers constructed by regulatable secondary nanostructure were achieved by adjusting TEOS content in the spinning solution, derived from which microporous carbon nanofibers with considerable mesopores (60–70% in mesoporosity), diverse secondary nanostructure (24–44 nm), and high specific surface area (1765–1890 m2 g−1) were prepared. The formation mechanism of the diverse secondary nanostructure in carbon nanofiber was proposed. The carbide-derived carbon nanofibers showed an excellent specific capacitance (316 F g−1 at 0.1 A g−1) and high-rate capability (186 F g−1 at 100 A g−1) due to the enhanced ion transportation, which was achieved by shortening micropore channels and offering convenient mesoporous channel towards microporous domains.

Flexible carbon nanobelt webs (CNBWs) with a hierarchical porous structure, considerable N- and/or O-containing surface functionalities were fabricated by electrospinning of phenolic resin/PVP/magnesium nitrate (MNH) solution, followed by curing, thermal treatment and picking. The effect of spinning humidity on the morphology of cured fibers was investigated. The results showed that low humidity was required for successful spinning and collection of the nanobelts. The addition of MNH played a crucial role in inhibiting inter-nanobelt adhesions and warping of nanobelts during thermal treatment and producing hierarchical porous structure. The increase in MNH content resulted in an enhancement in the specific surface area (SSA), micropore volume, and mesoporosity of the CNBWs. The achieved CNBWs displayed the maximum SSA of 779 m2 g−1 and a mesoporosity of 82%. The reduction in the number of warping endowed the CNBWs with face-to-face inter-nanobelt connection, then brought about a significant enhancement in conductivity and packing density of the CNBWs, which ultimately improved the rate performance and volumetric capacitance. The work proposed a feasible route for improving the conductivity and volumetric capacity of electrospun carbon nanofiber webs as the electrode for supercapacitors or batteries.

Transition-metal sulfide is one of the most promising anode candidates for lithium/sodium-ion batteries, but the extreme volume expansion leads to serious capacity decay during long-term cycling which limits its large-scale application. Herein, we designed a simple hydrothermal synthesis method combined with a membrane technology to fabricate flower-like SnS2 nanosheets uniformly anchored in the pores of the carbon membrane. The unique design demonstrated that an abundant membrane pore space was provided by the membrane technology for uniform growth of SnS2 nanosheet via a C S covalent bond. Meanwhile, the membrane pores and pore walls effectively relieved the volume expansion of SnS2 nanosheets during the charge/discharge process. Further, the even interpenetrating network structure of carbon membrane conductive scaffolds ensured its flexibility and structural integrity as anodes, which can provide plentiful charge transfer channels and large volume reservoirs for ion transmission. When the resulting composites were served as anodes, it achieved prominent electrochemical properties. The maximum reversible capacitance is 808.9 mA h g−1 for LIBs and 570.4 mA h g−1 for SIBs at 50 mA g−1, and outstanding rate capability was still maintained [333.3 mA h g−1 (LIBs) and 257.1 mA h g−1 (SIBs)] even at 2000 mA g−1. Moreover, almost no capacity loss was detected after the first few cycles during long-term cycles, fully suggesting that the membrane pores powerfully alleviated the volume expansion of SnS2 nanosheets and improved the cycle stability. Considering the positive effects of the unique porous structure provided by membrane technology on the electrochemical performance of the hybrid, the study offers an effective, simple, and low-cost strategy for large-scale production of SnS2-based anodes for the battery.

Construction of functional materials using low-dimensional carbons has attracted tremendous attention in the field of energy storage devices. Herein, porous carbon black (CB) is used as the dominant building unit to construct porous sub-micron carbon fibers by electrospinning and pyrolysis with polyacrylonitrile (PAN)-based pyrolytic carbon as the binder. Inheriting abundant pores and surface area from the porous CB, the resultant CB-based sub-micron fibers present considerable porosity and specific surface area. The PAN-based pyrolytic carbon endows the CB-based sub-micron carbon fibers with a considerable quantity of N/O-containing surface. CB content plays a crucial role in improving thermal stability, flexibility, and conductivity of the resultant sub-micron carbon fibers. The CB-based sub-micron carbon fibers present a considerable specific capacitance, excellent cycling stability and can be used electrodes for flexible supercapacitors.

Functional film with admirable flexibility, transparency and conductivity meets the requirements of directly contacting with the skin, is significantly desirable. Herein, we demonstrate a novel Janus bacterial celluloses (BCs)/MXene film prepared by a facile vacuum filtration, which shows the potential as skin-contactable materials. The BCs act as a substrate and framework to effectively trap the permeated MXene nanosheets rather than simply mixing, which lead to formation of Janus structure. A thin (∼1.732 μm), transparent, and light BCs/MXene film shows excellent tensile strength (up to ∼ 532.87 MPa) and folding-endurance (∼6152 cycles). More importantly, the strong interaction between BCs and MXene is proved by theoretical computations and experimental tests. In addition, it exhibits a specific shielding effectiveness (SSE/t) of ∼ 69455.2 dB cm2 g−1. These features make the composite film a promising candidate for wearable devices, military technology, and human electronic equipment.

Ideal lithium/sodium storage requires a simple and effective design of carbon-based anodes with appropriate morphologies/microstructures and excellent flexibility. Herein, an advanced flexible interpenetrating network carbon membrane with 3D hierarchical nanopore structure is designed and fabricated inspired by porous membrane technology via nonsolvent induced phase separation (NIPS) and carbonization. The interpenetrating network structure in the carbon membrane is generated by the NIPS membrane formation process, while the 3D hierarchical nano-porous structure is obtained from polymer decomposition during carbonization. The unique synergistic effect between the even interpenetrating network structure and the developed 3D hierarchical porous structure not only ensured structural integrity of the anodes and provided a high-volume ion transmission reservoir, but also endowed carbon membranes with multiple active sites for energy storage. As flexible anodes, the resulting carbon membranes achieved enhanced electrochemical properties by showing maximum reversible capacitance of 351.8 mA h g−1 in lithium storage and 237.4 mA h g−1 in SIBs at a current density of 50 mA g−1. In both LIBs and SIBs, the carbon membranes exhibit outstanding rate performance even at a high current density of 2000 mA g−1. They also show excellent long-term cycling stability with the coulomb efficiency maintained nearly 100 % after the first few cycles. Therefore, this work provides a simple and high-effective cross-disciplinary approach through membrane technology and carbon materials for the production of high-performance, low-cost carbon membranes for large-scale application anodes.

Hyperglycemia induces endothelial cells (ECs) dysfunction and vascular complications by accelerating ECs senescence. It also induces downregulation of sirtuins (SIRTs). However, the molecular mechanism involved in the regulation of ECs senescence by SIRT3 remains unclear. Here, we showed that high glucose (HG) decreased the expression level of SIRT3 in human umbilical vein endothelial cells (HUVECs), increased the proportion of cells expressing senescence-associated galactosidase (SA-gal), and HG damaged the cell's ability to form tubule networks on Matrigel. However, transfection with adenoviral construct including SIRT3 significantly inhibited HG-induced SA-gal activity, decreased p53 acetylation level at the site Lys 320 (k320), and overexpression of SIRT3 antagonized high glucose-induced angiogenic dysfunction. Our results suggested a possible molecular mechanism involving HG-SIRT3-p53 in ECs senescence.

Mesoporous carbon nanofibers (MCNFs) were prepared by electrospinning, carbonization and pickling process using phenolic resin as carbon source, pluronic F127 and Mg(NO 3 ) 2 ·6H 2 O as dual template. The obtained samples contained numerous oriented and parallel-to-fiber-axised mesopores and presented a specific surface area of 674 m 2 g −1 as well as high mesoporosity of 95%. The MCNFs were directly cut into electrodes free of binder for supercapacitors and tested in 6 M KOH electrolyte. In three-electrode system, the MCNFs showed a high specific capacitance (270 F g −1 at 0.2 A g −1 ) and outstanding rate performance (186 F g −1 at 20 A g −1 ). In two-electrode cell, the MCNFs presented a high capacitance of 160 F g −1 (86% of value at 0.1 A g −1 ) and excellent cycling stability (95% of capacitance retention after 5000 cycles). The free-standing nature and outstanding capacitance made the MCNFs a good candidate as electrode materials for next-generation flexible supercapacitors.

A novel carbon coated Fe3O4 nanoparticles (NPs)/expanded graphite (EG) composite has been prepared by in-situ pyrolysis of ferrecene on the nanosheets (NSs) of EG in an isolated atmosphere. Results indicated that the restack behavior of the NSs of EG which is easy to be induced by solvent removal was effectively avoided by this solution-free route. Well-crystallized Fe3O4-NPs with a dimension of

Microporous carbon nanofibers (CNFs) with a high specific surface area were prepared by sol–gel, electrospun, carbonization and pickling processes. Resol type phenolic resin (PF) acted as carbon source, tetraethyl orthosilicate (TEOS) worked as template and polyvinyl-pyrrolidone worked as spinning additives. The specific surface area and total pore volume of the CNFs were increased obviously with the increased amount of TEOS. A high specific area of 2164 m 2 g −1 , high microporosity and relatively narrow pore size distribution were achieved. The electrochemical performance was evaluated in 6 M KOH aqueous solution. The microporous CNFs exhibited outstanding electrochemical performance as binder-free electrode of supercapacitors, including a high specific capacitance (316 F g −1 at 0.2 A g −1 ), considerable rate performance (210 F g −1 at 20 A g −1 ) and good cycle stability (95% after cycling 1000 times). The microporous CNFs were promising electrode materials for high-performanced supercapacitors.

In the present work, transparent Y 2 O 3 ceramics were prepared via colloidal processing method from nano-sized Y 2 O 3 powders. The effects of triammonium citrate (TAC) on the colloid stability of aqueous suspensions of nano-sized Y 2 O 3 powders were studied. The surface properties of yttria powders were notably affected by the addition of TAC dispersant. The adsorption of TAC on the particle surface shifts the IEP to lower pH values and increases the absolute zeta potential in alkaline region. Rheological characterization of the investigated system revealed an optimal dispersant concentration of 1 wt%, which correlated well with the saturation adsorption of TAC on Y 2 O 3 powder surfaces. The suspensions with solid loadings up to 35 vol% were achieved with further addition of Tetramethylammonium hydroxide (TMAH) into the dispersing system. The consolidated green bodies were treated by cold isostatic pressing to further increase the green density. Transparent Y 2 O 3 ceramics were prepared after vacuum-sintering at 1700 °C for 5 h. The transmittances of the sample were 74.5% at 800 nm and 79.8% at 2000 nm, respectively.

A nitrogen-doped hierarchical porous carbon has been prepared through one-step KOH activation of pitch oxide/graphene oxide composite. At a low weight ratio of KOH/composite (1:1), the as-prepared carbon possesses high specific surface area, rich nitrogen and oxygen, appropriate mesopore/micropore ratio and considerable small-sized mesopores. The addition of graphene oxide plays a key role in forming 4 nm mesopores. The sample PO-GO-16 presents the characteristics of large surface area (2196 m(2) g(-1)), high mesoporosity (47.6%), as well as rich nitrogen (1.52 at.%) and oxygen (6.9 at.%). As a result, PO-GO-16 electrode shows an outstanding capacitive behavior: high capacitance (296 F g(-1)) and ultrahigh-rate performance (192 F g(-1) at 10 A g(-1)) in 6 M KOH aqueous electrolyte. The balanced structure characteristic, low-cost and high performance, make the porous carbon a promising electrode material for supercapacitors.