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[Display omitted] Poor mechanical strength at working temperature and low ionic conductivity seriously hinder the application of poly(ethylene oxide) (PEO)-based solid polymer electrolytes (SPEs) in high performance all-solid-state lithium metal batteries (LMBs). Here, we design and prepare a series of rigid-flexible coupling network SPEs (RFN-SPEs) with soft poly(ethylene glycol) (PEG) chains and rigid crosslinkers containing the benzene structure. Compared with soft crosslinkers, rigid crosslinkers provide the same amount of active crosslinking points with smaller molecular weight, and meanwhile enhance the mechanical strength of the network. Therefore, based on the rigid crosslinkers, RFN-SPEs exhibit synchronously improved ionic conductivity and mechanical strength. With these RFN-SPEs, symmetrical cells can be cycled for over 2100 h at 0.5 mA cm−2. Meanwhile, stable cycling and high-rate capability could be achieved for LMBs, revealing that SPEs with the rigid-flexible coupling network are promising electrolyte systems for all-solid-state LMBs. [ABSTRACT FROM AUTHOR]

Efficient separation of particles has ever-growing importance in both fundamental research and nanotechnological applications. However, such particles usually suffer from some fluctuations from external surroundings and outside intervention from unknown directions. Here, we numerically investigate the transport of Brownian particles in a straight channel with regular arrays of equilateral triangle obstacles. The particles can be rectified by the triangle obstacles under the action of an oscillating (square wave) force. At the given amplitude and frequency of the oscillating force, the transport is sensitively dependent on the force direction and particle size. In the cases of longitudinal and transversal oscillating force, the particles with different sizes exhibit different transport behaviors. Interestingly, under a constant force in the longitudinal direction, the phenomenon of particle separation is observed, where the particles with different radii will move in different directions. Furthermore, we also study the transport of Brownian particles driven by a tilt oscillating force. By choosing proper force directions, we can observe the gating phenomenon and transport reversal. Under different driving conditions, we can separate particles of different sizes and make them move in opposite directions. [ABSTRACT FROM AUTHOR]

Transport of chiral active particles is numerically investigated in a two-dimensional ring-shaped channel. The ring-shaped channel is transversal asymmetric and can induce the directed transport (rotation) of chiral active particles. For the particles with small chirality, they slide along the outer boundary of the channel. For the particles with large chirality, the particles move along some small local circular orbits and can also exhibit directed rotation. Moreover, the rotation effect can be strongly enhanced by modifying the inner boundary geometry. Based on the study of particle rotation, we further study the separation of active particles with different chiralities. It is found that the particles with different chiralities may be distributed in different regions of the ring-shaped channel. Interestingly, these particles can be completely separated by shifting the channel's inner boundary or adding a blocking plate in the channel. Our results may be useful for understanding relevant experimental phenomena and provide a scheme for the separation of binary mixtures. [ABSTRACT FROM AUTHOR]

The transport of active particles in straight channels is numerically investigated. The periodic wedge-shaped barriers can produce the asymmetry of the system and induce the directed transport of the active particles. The direction of the transport is determined by the apex angle of the wedge-shaped barriers. By confining the particles in channels with hard and soft walls, the transport exhibits similar behaviors. The average velocity is a peaked function of the translational diffusion, while it decreases monotonously with the increase of the rotational diffusion. Moreover, the simulation results show that the transport is sensitive to the parameters of the confined structures, such as the pore width, the intensity of potential, and the channel period. [ABSTRACT FROM AUTHOR]

Transport of chiral active particles in a symmetric periodic potential is investigated in the presence of a constant force. It is found that due to chirality of active particles the transversal constant force can break the symmetry of the system and induce a longitudinal net current. There exists an optimal constant force at which the rectification is maximal. Remarkably, longitudinal current reversals can occur by suitably tailoring the transversal constant force. Therefore, particles with different chiralities move to different directions and can be effectively separated. [ABSTRACT FROM AUTHOR]

A multiscale sequence of simulation should be used to predict properties of materials under irradiation. Binary collision theory and molecular dynamics (MDs) method are commonly used to characterize the displacement cascades induced by neutrons in a material. In order to reduce the clock time spent for the MD simulation of damages induced by high-energy primary knock-on atoms (PKAs), the damage zones were split into sub-cascade according to the sub-cascade formation criteria. Two well-known codes, Geant4 and TRIM, were used to simulate high-energy PKA-induced cascades in B 4 C and then produce the secondary knock-on atom (SKA) energy spectrum. It has been found that both high-energy primary knock-on B and C atoms move a long range in the boron carbide. These atoms produce sub-cascades at the tip of trajectory. The energy received by most of the SKAs is <10 keV, which can be used as input to reduce the clock time spent for MD simulation. [ABSTRACT FROM AUTHOR]

Transport of active particles is numerically investigated in a two-dimensional period channel. In the presence of a transverse ac force, the directed transport of active particles demonstrates striking behaviors. By adjusting the amplitude and the frequency of the transverse ac force, the average velocity will be influenced significantly and the direction of the transport can be reversed several times. Remarkably, it is also found that the direction of the transport varies with different self-propelled speeds. Therefore, particles with different self-propelled speeds will move to the different directions, which is able to separate particles of different self-propelled speeds. [ABSTRACT FROM AUTHOR]

Rectified transport of self-propelled particles in an asymmetric period potential is numerically investigated by employing a feedback control protocol. The feedback control is switched on and off depending on the direction of the self-propelled speed. It is found that the direction of the transport is determined by the asymmetry of the potential and the feedback control strength. In the presence of feedback control, the directed transport can be improved significantly by increasing the feedback control strength under appropriate conditions. For large ensembles of particles, however, the feedback control will not obviously affect the transport of self-propelled particles. The present studies may be relevant to some applications in biology and nanotechnology, and provide the predicting results in experiments of active particles. [ABSTRACT FROM AUTHOR]

In the present paper, we investigate the behavior of two-dimensional atom localization in a five-level M-scheme atomic system driven by two orthogonal standing-wave fields. We find that the precision and resolution of the atom localization depends on the probe field detuning significantly. And because of the effect of the microwave field, an atom can be located at a particular position via adjusting the system parameters. [ABSTRACT FROM AUTHOR]

We investigate the behavior of two-dimensional atom localization in an inverted-Y system driven by one coherent field and two standing-wave fields. The position probability distribution of the atom passing through the spatial-position-dependent standing-wave fields can be determined by measuring the spontaneously emitted photon. It is found that high-precision two-dimensional atom localization can be obtained by choosing appropriate system parameters. [ABSTRACT FROM AUTHOR]

We investigate the dispersive and absorptive properties of an N-type four-level atomic system in three coherent fields, and consider the susceptibility mathematically. It is shown that the group velocity of the probe field exhibits sub- and super-luminal under some conditions, meanwhile the absorption coefficient keeps zero during the occurrence and transition process of sub- and super-luminal pulses. [ABSTRACT FROM AUTHOR]

Transport of the finite size spherical Brownian particles is investigated in confined narrow channels with varying cross-section width. Applying the Fick-Jacobs approximation, we obtain the expressions of the particle current, the effective diffusion coefficient, and the coherence level of Brownian transport (the Péclet number). For the case of the biased constant force, the dependencies of the nonlinear mobility, the effective diffusion coefficient, and the Péclet number on the particle size exhibit striking behaviors. The Péclet number decreases with increasing the radius of the particle which shows that the big sizes of the particles reduce the coherence level of Brownian transport. There exists an optimized value of the radius at which the effective diffusion coefficient is maximal. For the case of the asymmetric unbiased force, due to the competition between the spatial asymmetry and the temporal asymmetry, the transport directions of the particles depend very sensitively on the size of the particle. Particles larger than a given threshold radius move to the left, whereas particles smaller than that move to the right. Therefore, one can separate particles of different radii and make them move towards opposite directions. [ABSTRACT FROM AUTHOR]

A random fuse network model is proposed to study the steplike negative differential resistance (NDR) in spatial confined manganite structures. Different underlying breaking processes due to self-heating effects are exhibited for various disorder strength of the networks. NDR multisteps are reproduced and the corresponding evolution of current morphology is present. Simulations results for the networks with various sizes show that confined geometry will sharpen the steplike NDR response in I-V curves, which agrees with experimental results well. [ABSTRACT FROM AUTHOR]

The proton transfer mechanism on the carbon cathode surface has been considered as an effective way to boost the electrochemical performance of Zn-ion hybrid supercapacitors (SCs) with both ionic liquid and organic electrolytes. However, cheaper, potentially safer, and more environmental friendly supercapacitor can be achieved by using aqueous electrolyte. Herein, we introduce the proton transfer mechanism into a Zn-ion hybrid supercapacitor with the ZnSO4 aqueous electrolyte and functionalized activated carbon cathode materials (FACs). We reveal both experimentally and theoretically an enhanced performance by controlling the micropores structure and hydrogen-containing functional groups (–OH and –NH functions) of the activated carbon materials. The Zn-ion SCs with FACs exhibit a high capacitance of 435 F g−1 and good stability with 89% capacity retention over 10,000 cycles. Moreover, the proton transfer effect can be further enhanced by introducing extra hydrogen ions in the electrolyte with low pH value. The highest capacitance of 544 F g−1 is obtained at pH = 3. The proton transfer process tends to take place preferentially on the hydroxyl-groups based on the density functional theory (DFT) calculation. The results would help to develop carbon materials for cheaper and safer Zn-ion hybrid SCs with higher energy. [ABSTRACT FROM AUTHOR]

Transport of interacting Brownian particles in a periodic potential is investigated in the presence of an ac force and a dc force. From Brownian dynamic simulations, we find that both the interaction between particles and the thermal fluctuations play key roles in the absolute negative mobility (the particle noisily moves backwards against a small constant bias). When no the interaction acts, there is only one region where the absolute negative mobility occurs. In the presence of the interaction, the absolute negative mobility may appear in multiple regions. The weak interaction can be helpful for the absolute negative mobility, while the strong interaction has a destructive impact on it. [ABSTRACT FROM AUTHOR]

Objective. To explore the efficacy of long-term use of Chinese herbal medicine (CHM) on survival time of lung cancer. Methods. We conducted a retrospective cohort study on lung cancer patients. A propensity score matching (PSM) was performed to balance the covariates. Progression-free survival (PFS) was the primary endpoint and overall survival (OS) was the secondary endpoint. Patients who received CHM therapy from the initial date of diagnosis of lung cancer were included in the CHM group. Patients who were not treated with CHM during the same interval were categorized in the control group. A Cox regression model was used to explore the prognostic factors related to lung cancer. Hazard ratios of different subgroups were also analyzed. Results. A total of 1134 patients were included in our study: 761 patients were in the CHM group and 373 patients were in the control group. After PSM, the mPFS and mOS in the CHM group were 70.4 months and 129.1 months, respectively, while the mPFS and mOS in the control group were 23.8 months and 99.7 months, respectively. The results of survival analysis on each stage demonstrated that patients may benefit from the long-term CHM treatment especially for patients with early stage. One-year to ten-year progression-free survival rates in the CHM group were higher than those in the control group (p < 0.001). COX multivariate regression analysis indicated that CHM treatment, female, low age at diagnosis, early tumor stage, and surgery were independent protective factors against recurrence and metastasis of lung cancer. Subgroup analysis showed that CHM treatment could reduce the risk of recurrence and metastasis in each subgroup (p < 0.01). Conclusion. Long-term CHM treatment with the Fuzheng Quxie Formula, which can be flexibly applied in the course of lung cancer treatment, not only has a positive influence on the progression-free survival time of lung cancer patients, but also reduces the risk of recurrence and metastasis of lung cancer. [ABSTRACT FROM AUTHOR]

Directed transport of an active polymer chain with chirality is investigated in a transversal asymmetric channel. The polymer chain is composed of a chiral active particle and several passive particles. Due to the interplay of the chirality of the chain and the transversal asymmetry, the polymer chain can be rectified. The direction of the transport is determined by the competition of the chirality of the chain and the properties of the channel. Remarkably, we can observe current reversals by varying the system parameters such as self-propelled speed, the chirality, the length of the chain, and the channel parameters. Our finds are relevant to the experimental pursuit of the controlling of the active polymer in periodic channel. • Due to the interplay of the chirality and the transversal asymmetry, the chain can be rectified. • The transport direction is determined by the competition of the chirality and the channel properties. • We can observe current reversals by varying the system parameters. [ABSTRACT FROM AUTHOR]

Abstract To find a sacrificed layer on walls of silicon macropore, the microporous silicon (MPS) was formed on the wall of straight silicon macropore (SSMP) by electrochemical etching on n-type silicon. The front side illumination was used to control the thickness of MPS on SSMP wall. The experiment showed that the thickness of MPS was more easily controlled by changing the illumination than the applied electric field and etching electrolyte. So the injected carrier model (ICM) was proposed for deducing an experimental equation between the illuminance and MPS thickness. Light attenuation in silicon was confirmed as the major cause of MPS formation in SSMP. ICM model could be used to predict the porous structure etched by front side illumination on n-type silicon. Highlights • Front side illumination is found to affects the thickness of microporous silicon in straight macropores apparently. • The injected carrier model is proposed for deducing the experimental equation between illuminance and MPS thickness. • The function of light attenuation and current change in the formation mechanism of microporous silicon in straight macropores is confirmed. [ABSTRACT FROM AUTHOR]

The anode material of sodium ion battery (SIB) as the focus of limiting its development has caused an intensive research on the SIB research field. Ferrous sulfide (FeS), as transition metal sulfide with high specific capacity and high tap density, is one of the potential anode materials for SIBs. However, its low electrical conductivity, large volume change, and inherent polysulfide shuttle issue present challenges for its practical application. Herein, we present a method for making carbon-coated ferrous sulfide (FeS@C) using a quick-freezing method to inhibit gel composition segregation. The FeS particles with high purity are uniformly encapsulated by the carbon layer, which improves its conductivity and stability. Moreover, a polyphenylene sulfide based solid state separator (PPS-SSS) with polyethylene (PE) anodic protection (PE-PPS-CSSS) is also introduced. And the tetrachlorobenzoquinone (TCBQ) is used to modify the PPS particles interface in the separator and adsorb the polysulfides to inhibit the shuttle of polysulfides and reduce the deactivited Na 2 S, which greatly improves the stability of the battery. The half-cell has an initial coulomb efficiency (CE) of ∼90% and a specific capacity of 360 mAh g−1. Meanwhile, a full cell with Na 3 V 2 (PO 4) 3 (NVP) and PE-PPS-CSSS has 81% capacity retention for 600 cycles at 1 C. • Quick-freezing sol-gel method was used to prepare high purity FeS@C. • An initial ICE of ∼90% for FeS@C anode was achieved without any pre-activation process. • PE-PPS-CSSS inhibited the shuttle of polysulfides while reducing deactivated Na 2S. • PE-PPS-CSSS promoted the uniform anodic conversion reaction. • The NVP/FeS@C full cell had 600 stable cycles at 1 C with capacity retention of 80.9%. [ABSTRACT FROM AUTHOR]

Silicon macropore arrays are fabricated on lightly-doped n-Si by electrochemical etching. The opening diameter, inner diameter, and wall thickness of the macropores are observed to depend on HF concentration and current. A current reconstruction model is proposed to elucidate the formation mechanism of the macropores. Two geometric models are established for the silicon macropores according to the experimental results. The finite element method is used to simulate the electric field and current in the electrolyte-silicon system. The reconstruction of electrical current on the silicon macropore arrays is described by simulating the electric field and current. The ratio of major to minor semi-axes of the elliptical pore ( b / a ) decreases with increasing the ratio of diameter to wall thickness as confirmed experimentally. The results indicate that the b / a ratio is correlated with the HF concentration and applied voltage. [ABSTRACT FROM AUTHOR]

Abstract: Tungsten films were deposited on stainless steel (SS) with ion beam mixing (IBM) or electron beam alloying (EBA) treatment. The ductile–brittle transition behaviors of the specimens were investigated by means of instrumented Charpy impact test at a series of temperature, and SEM was used to observe the morphology of the cross section. Impact tests show that different treatment methods with W films do not have much influence on crack initiation, while EBA treatment with W films can more effectively prevent crack propagation, namely improve the impact toughness of SS than using IBM treatment. The reason that caused this difference was discussed. [Copyright &y& Elsevier]

• CoS 2 @CNFs films have been synthesized as a novel binder-free cathode for AIBs. • 3D network CNFs with CoS 2 nanoparticles uniform distribution contribute to the excellent electrochemical performance. • New substance of AlCo 2 S 4 is discovered during discharge/charge process. • Ex situ XRD, XPS and DFT are performed to reveal the charge-storage mechanism. Rechargeable aluminum ion battery (AIB) is considered to be a promising next-generation battery system that can meet future needs for the large scale energy storage, because of its high energy density and low-cost. For the development of long life AIBs, the most urgent challenge is to explore suitable cathode and understand the exact Al charge/discharge mechanism. Herein, a novel binder-free cathode material, CoS 2 @carbon nanofibers, was synthetized by electrospinning and annealing process. As a result, a specific capacity of ~80 mAh g−1 was maintained after 500 cycles under a current density of 200 mA g−1, which was higher than that of AIBs using a normal CoS 2 cathode with binder. Significantly, even at a high current density of 500 mA g−1, the battery can still retain 74 mAh g−1 after 1200 cycles. Furthermore, its working mechanism was explored in combination with ex-situ XRD, XPS and first-principles calculations, which revealed that the reversible conversion reaction of CoS 2 /AlCo 2 S 4. The novel binder-free CoS 2 @Carbon nanofibers cathodes are meaningful for the further design of binder-free AIBs with low-cost and long cycling life. [ABSTRACT FROM AUTHOR]

Supercabatteries combine the advantages of high power and energy density performances. However, the electrodes are always fabricated using high surface area materials and traditional slurry coating method containing the solvent mixing and drying processes, which are less controlled, energy-intensive, and environmentally unfriendly. Herein, we report a solvent-free method in pilot stage, combining a high-speed air blowing, hot-rolling, and hot overlying process. The carbon materials with high content of 40% are mixed in the LiFePO 4 -activated carbons cathode and Li 4 Ti 5 O 12 -activated carbons anode, respectively. The compact densities of the thick solvent-free electrodes (120 μm, one-side) are almost ~1.6 times of the values for the slurry coating electrodes. The solvent-free full cells show capacitive linear charge/discharge curves before the cell voltage plateaus. And these linear curves further mitigate the internal resistance drop at −40 °C using acetonitrile-assistant carbonate-based eutectic electrolytes. The full cell delivers high areal capacity of 1.4 mAh cm−2 and volume energy density of 95 Wh L−1, which is almost 2 times higher than that of the slurry coating full cell. Moreover, the supercabattery with acetonitrile-assistant electrolyte shows excellent cycling retention of 92% for over 5000 cycles due to the self-passivated solid electrolyte interface formation and stable fibrous polytetrafluoroethylene net-like binding structure. Image 1 • Li-ion supercabattery using LiFePO 4 - and Li 4 Ti 5 O 12 -based electrodes with 40% carbons. • Solvent-free electrodes combined air blowing, hot-rolling and overlying process. • Novel supercabattery shows high areal capacity, energy density and better cycling. • Contribution of capacitive controlled current can reach up to 68% at high rates. • Acetonitrile-assistant eutectic electrolytes ensured the −40 °C performance. [ABSTRACT FROM AUTHOR]