Viability of all-solid-state lithium metal battery coupled with oxide solid-state electrolyte and high-capacity cathode

Owing to the utilization of lithium metal as anode with the ultrahigh theoretical capacity density of 3860 mA h g^(-1)and oxide-based ceramic solid-state electrolytes(SE),e.g.,garnet-type Li7La_(3)Zr_(2)O_(12)(LLZO),all-state-state lithium metal batteries(ASLMBs)have been widely accepted as the promising alternatives for providing the satisfactory energy density and safety.However,its applications are still challenged by plenty of technical and scientific issues.In this contribution,the co-sintering temperature at 500℃is proved as a compromise method to fabricate the composite cathode with structural integrity and declined capacity fading of LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2)(NCM).On the other hand,it tends to form weaker grain boundary(GB)inside polycrystalline LLZO at inadequate sintering temperature for LLZO,which can induce the intergranular failure of SE during the growth of Li filament inside the unavoidable defect on the interface of SE.Therefore,increasing the strength of GB,refining the grain to 0.4μm,and precluding the interfacial defect are suggested to postpone the electro-chemo-mechanical failure of SE with weak GB.Moreover,the advanced sintering techniques to lower the co-sintering temperature for both NCM-LLZO composite cathode and LLZO SE can be posted out to realize the viability of state-of-the-art ASLMBs with higher energy density as well as the guaranteed safety.

Revealing the Role of Defect in 3D Graphene-Based Photocatalytic Composite for Efficient Elimination of Antibiotic and Heavy Metal Combined Pollution

Defect engineering can give birth to novel properties for adsorption and photocatalysis in the control of antibiotics and heavy metal combined pollution with photocatalytic composites.However,the role of defects and the process mechanism are complicated and indefinable.Herein,TiO_(2)/CN/3DC was fabricated and defects were introduced into the tripartite structure with separate O_(2)plasma treatment for the single component.We find that defect engineering can improve the photocatalytic activity,attributing to the increase of the contribution from h^(+)and OH.In contrast to TiO_(2)/CN/3DC with a photocatalytic tetracycline removal rate of 75.2%,the removal rate of TC with D-TiO_(2)/CN/3DC has increased to 88.5%.Moreover,the reactive sites of tetracycline can be increased by adsorbing on the defective composites.The defect construction on TiO_(2)shows the advantages in tetracycline degradation and Cu^(2+)adsorption,but also suffers significant inhibition for the tetracycline degradation in a tetracycline/Cu^(2+)combined system.In contrast,the defect construction on graphene can achieve the cooperative removal of tetracycline and Cu^(2+).These findings can provide new insights into water treatment strategies with defect engineering.

Selection of Negative Charged Acidic Polar Additives to Regulate Electric Double Layer for Stable Zinc Ion Battery

Zinc-ion batteries are promising for large-scale electrochemical energy storage systems,which still suffer from interfacial issues,e.g.,hydrogen evolution side reaction(HER),self-corrosion,and uncontrollable dendritic Zn electrodeposition.Although the regulation of electric double layer(EDL)has been verified for interfacial issues,the principle to select the additive as the regulator is still misted.Here,several typical amino acids with different characteristics were examined to reveal the interfacial behaviors in regulated EDL on the Zn anode.Negative charged acidic polarity(NCAP)has been unveiled as the guideline for selecting additive to reconstruct EDL with an inner zincophilic H_(2)O-poor layer and to replace H_(2)O molecules of hydrated Zn^(2+)with NCAP glutamate.Taking the synergistic effects of EDL regulation,the uncontrollable interface is significantly stabilized from the suppressed HER and anti-self-corrosion with uniform electrodeposition.Consequently,by adding NCAP glutamate,a high average Coulombic efficiency of 99.83%of Zn metal is achieved in Zn|Cu asymmetrical cell for over 2000 cycles,and NH4V4O10|Zn full cell exhibits a high-capacity retention of 82.1%after 3000 cycles at 2 A g^(-1).Recapitulating,the NCAP principle posted here can quicken the design of trailblazing electrolyte additives for aqueous Zn-based electrochemical energy storage systems.

Network analysis and spatial agglomeration of China’s high-speed rail: A dual network approach

China has the largest high-speed railway(HSR) system in the world, and it has gradually reshaped the urban network.The HSR system can be represented as different types of networks in terms of the nodes and various relationships(i.e.,linkages) between them. In this paper, we first introduce a general dual network model, including a physical network(PN)and a logical network(LN) to provide a comparative analysis for China’s high-speed rail network via complex network theory. The PN represents a layout of stations and rail tracks, and forms the basis for operating all trains. The LN is a network composed of the origin and destination stations of each high-speed train and the train flows between them. China’s high-speed railway(CHSR) has different topological structures and link strengths for PN in comparison with the LN. In the study, the community detection is used to analyze China’s high-speed rail networks and several communities are found to be similar to the layout of planned urban agglomerations in China. Furthermore, the hierarchies of urban agglomerations are different from each other according to the strength of inter-regional interaction and intra-regional interaction, which are respectively related to location and spatial development strategies. Moreover, a case study of the Yangtze River Delta shows that the hub stations have different resource divisions and are major contributors to the gap between train departure and arrival flows.

Spin-exchange relaxation of naturally abundant Rb in a K-Rb-21Ne self-compensated atomic comagnetometer

The total effective spin-exchange relaxation of naturally abundant Rb in a K–Rb–21Ne comagnetometer is analyzed,and the results show that the coexistence of 87Rb and 85Rb isotopes in the same volume can lead to a large extra spinexchange broadening compared to pure 87Rb.This broadening mainly comes from the contribution of the equivalent reduction in the Rb spin-exchange rate.On this basis,an approximate relaxation model is proposed and experimentally demonstrated to be more accurate than that from a previous work.This study also provides a method for determining the properties of alkali-metal vapor cells.

In situ temperature measurement of vapor based on atomic speed selection

We demonstrate an experimental method for the in situ temperature measurement of atomic vapor using the saturated absorption spectrum. By separately manipulating the frequency of the pump and probe beams, the position of the crossover peaks can move along the spectrum. Different velocity classes of atoms contribute to the crossover during the movement. We study the relationship between the intensity change of peaks and vapor temperature. Our experimental result around room temperature shows a deviation of less than 0.3 K. Compared with traditional thermometry using absorption spectroscopy, higher accuracy can theoretically be achieved with real-time thermometry.

NH_(3)‑Induced In Situ Etching Strategy Derived 3D‑Interconnected Porous MXene/Carbon Dots Films for High Performance Flexible Supercapacitors

2D MXene(Ti_(3)CNT_(x))has been considered as the most promising electrode material for flexible supercapacitors owing to its metallic conductivity,ultra-high capacitance,and excellent flexibility.However,it suffers from a severe restacking problem during the electrode fabrication process,limiting the ion transport kinetics and the accessibility of ions in the electrodes,especially in the direction normal to the electrode surface.Herein,we report a NH_(3)-induced in situ etching strategy to fabricate 3D-interconnected porous MXene/carbon dots(p-MC)films for high-performance flexible supercapacitor.The pre-intercalated carbon dots(CDs)first prevent the restacking of MXene to expose more inner electrochemical active sites.The partially decomposed CDs generate NH_(3)for in situ etching of MXene nanosheets toward 3D-interconnected p-MC films.Benefiting from the structural merits and the 3D-interconnected ionic transmission channels,p-MC film electrodes achieve excellent gravimetric capacitance(688.9 F g^(-1)at 2 A g^(-1))and superior rate capability.Moreover,the optimized p-MC electrode is assembled into an asymmetric solid-state flexible supercapacitor with high energy density and superior cycling stability,demonstrating the great promise of p-MC electrode for practical applications.

Fringe removal algorithms for atomic absorption images:A survey

The fringe noises disrupt the precise measurement of the atom distribution in the process of the absorption images.The fringe removal algorithms have been proposed to reconstruct the ideal reference images of the absorption images to remove the fringe noises.However,the focus of these fringe removal algorithms is the association of the fringe removal performance with the physical systems,leaving the gap to analyze the workflows of different fringe removal algorithms.This survey reviews the fringe removal algorithms and classifies them into two categories:the imagedecomposition based methods and the deep-learning based methods.Then this survey draws the workflow details of two classical fringe removal algorithms,and conducts experiments on the abs DL ultracold image dataset.Experiments show that the singular value decomposition(SVD)method achieves outstanding performance,and the U-net method succeeds in implying the image inpainting idea.The main contribution of this survey is the interpretation of the fringe removal algorithms,which may help readers have a better understanding of the research status.

Compound-induced transparency in three-cavity coupled structure

We propose a three-cavity coupled cavity optomechanical(COM)structure with tunable system parameters and theoretically investigate the probe-light transmission rate.Numerical calculation of the system’s spectra demonstrates distinctive compound-induced transparency(CIT)characteristics,including multiple transparency windows and sideband dips,which can be explained by a coupling between optomechanically-induced transparency(OMIT)and electromagnetically-induced transparency.The effects of optical loss(gain)in the cavity,number and topology of active cavity,tunneling ratio,and pump laser power on the CIT spectrum are evaluated and analyzed.Moreover,the optical group delay of CIT is highly controllable and fast–slow light inter-transition can be achieved.The proposed structure makes possible the advantageous tuning freedom and provides a potential platform for controlling light propagation and fast–slow light switching.

Atomic Spin Polarization Controllability Analysis:A Novel Controllability Determination Method for Spin-Exchange Relaxation-Free Co-Magnetometers

This paper investigates the atomic spin polarization controllability of spin-exchange relaxation-free co-magnetometers(SERFCMs).This is the first work in the field of controllability analysis for the atomic spin ensembles systems,whose dynamic behaviors of spin polarization are described by the Bloch equations.Based on the Bloch equations,a state-space model of the atomic spin polarization for SERFCM is first established,which belongs to a particular class of nonlinear systems.For this class of nonlinear systems,a novel determination method for the global state controllability is proposed and proved.Then,this method is implemented in the process of controllability analysis on the atomic spin polarization of an actual SERFCM.Moreover,a theoretically feasible and reasonable solution of the control input is proposed under some physical constraints,with whose limitation of realistic conditions,the controller design can be accomplished more practically and more exactly.Finally,the simulation results demonstrate the feasibility and validation of the proposed controllability determination method.

Variable optical chirality in atomic assisted microcavity

The manipulating of optical waves in a microcavity is essential to developing the integrated optical devices.Generally,the two eigenmodes in a whispering-gallery-mode(WGM)microcavity possess chiral symmetry.Here we show the chiral symmetry breaking is induced by the asymmetric backscattering of counter-propagating optical waves in a whisperinggallery-mode(WGM)microcavity with a cavity-made slot filled with atomic vapor.Through tuning the dispersion relation of the atomic vapor in the cavity-made slot,the chiral modes are continuously steered.The mode frequency splitting in the transmission and reflection spectra stem from the chiral symmetry breaking of the two eigenmodes.The displacement sensitivity of the proposed system in response to the length variation of cavity-made slot exhibits a high sensitivity value of 15.22 THz/nm.

Superfluid-Mott-Insulator Transition in an Optical Lattice with Adjustable Ensemble-Averaged Filling Factors

We study the quantum phase transition from a superfluid to a Mott insulator of ultracold atoms in a threedimensional optical lattice with adjustable filling factors.Based on the density-adjustable Bose-Einstein condensate we prepared,the excitation spectrum in the superfluid and the Mott insulator regime is measured with different ensemble-averaged filling factors.We show that for the superfluid phase,the center of the excitation spectrum is positively correlated with the ensemble-averaged filling factor,indicating a higher sound speed of the system.For the Mott insulator phase,the discrete feature of the excitation spectrum becomes less pronounced as the ensemble-averaged filling factor increases,implying that it is harder for the system to enter the Mott insulator regime with higher filling factors.The ability to manipulate the filling factor affords further potential in performing quantum simulation with cold atoms trapped in optical lattices.

Combined effect of WS_(2) and Ti_(3)C_(2)T_(x) MXene favors oil-based ultra-low friction on rough steel-steel interface at elevated temperatures

The lubrication performance of liquids is severely restricted and is degraded in high-temperature environments. Stable and reliable lubrication in high temperature environments has been a long-standing goal in various industrial fields. In this study,WS_(2)and Ti_(3)C_(2)T_(x)MXene nanoflakes were used as oil-based lubricant additives to generate ultra-low friction and even superlubricity(friction coefficient of ~0.007) at elevated temperatures(400℃), which has hitherto not been achieved by both individual pristine materials, WS_(2)and Ti_(3)C_(2)T_(x)MXene. Viscosity and thermogravimetric characterization revealed improvements in the high-temperature rheological properties and thermal stability of the lubricating base oil, indicating improved loadbearing and continuous lubrication capabilities at elevated temperatures. X-ray photoelectron spectroscopy, transmission electron microscopy, and atomic force microscopy demonstrated that the formation of an iron/titanium/tungsten-rich oxide lubricious thin film at the sliding interface reduced the interfacial shear stress, which was responsible for the observed friction and wear reductions at high contact pressures(> 1.1 GPa). Although the titanium/tungsten oxide film was gradually removed after prolonged sliding, a sufficiently thick iron oxide film maintained a low friction coefficient for at least 2 h. The improved surface quality facilitates the achievement of ultra-low friction and reduced wear. The proposed lubrication methodology has a broad utilization potential as a wear-reduction strategy across various industrial fields at elevated temperatures.

Tertiary orientation structures enhance the piezoelectricity of MXene/PVDF nanocomposite

With the increasing demand for flexible piezoelectric sensor components,research on polyvinylidene fluoride(PVDF)based piezoelectric polymers is mounting up.However,the low dipole polarization and disordered polarization direction presented in PVDF hinder further improvement of piezoelectric properties.Here,we constructed an oriented tertiary structure,consisting of molecular chains,crystalline region,and MXene sheets,in MXene/PVDF nanocomposite via a temperature-pressure dual-field regulation method.The highly oriented PVDF molecular chains form approximately 90%of theβphase.In addition,the crystalline region structure with long-range orientation achieves out of plane polarization orientation.The parallel orientation arrangement of MXene effectively enhances the piezoelectric performances of the nanocomposite,and the current output of the device increases by nearly 23 times.This high output device is used to monitor exercise action,exploring the potential applications in wearable electronics.

Knockout of miR396 genes increases seed size and yield in soybean

Yield improvement has long been an important task for soybean breeding in the world in order to meet the increasing demand for food and animal feed.mi R396 genes have been shown to negatively regulate grain size in rice,but whether mi R396 family members may function in a similar manner in soybean is unknown.Here,we generated eight soybean mutants harboring different combinations of homozygous mutations in the six soybean mi R396genes through genome editing with clustered regularly interspaced palindromic repeats(CRISPR)/CRISPR-associated nuclease(Cas)12SF01 in the elite soybean cultivar Zhonghuang 302(ZH302).Four triple mutants(mir396aci,mir396acd,mir396adf,and mir396cdf),two quadruple mutants(mir396-abcd and mir396acfi),and two quintuple mutants(mir396abcdf and mir396bcdfi)were characterized.We found that plants of all the mir396 mutants produced larger seeds compared to ZH302 plants.Field tests showed that mir396adf and mir396cdf plants have significantly increased yield in growth zones with relatively high latitude which are suited for ZH302 and moderately increased yield in lower latitude.In contrast,mir396abcdf and mir396bcdfiplants have increased plant height and decreased yield in growth zones with relatively high latitude due to lodging issues,but they are suited for low latitude growth zones with increased yield without lodging problems.Taken together,our study demonstrated that loss-of-function of mi R396 genes leads to significantly enlarged seed size and increased yield in soybean,providing valuable germplasms for breeding high-yield soybean.

Erratum to:Tertiary orientation structures enhance the piezoelectricity of MXene/PVDF nanocomposite

In the first page of the original version of this paper,the Received date should be“10 October 2023”instead of“10 October 2013”.

Reliability estimation of rotary lip seal in aircraft utility system based on time-varying dependence degradation model and its experimental validation

With several attractive properties, rotary lip seals are widely used in aircraft utility system, and their reliability estimation has drawn more and more attention. This work proposes a reliability estimation approach based on time-varying dependence analysis. The dependence between the two performance indicators of rotary lip seals, namely leakage rate and friction torque, is modeled by time-varying copula function with polynomial to denote the time-varying parameters, and an efficient copula selection approach is utilized to select the optimal copula function. Parameter estimation is carried out based on a Bayesian method and the reliability during the whole lifetime is calculated based on a Monte Carlo method. Degradation test for rotary lip seal is conducted and the proposed model is validated by test data. The optimal copula function and optimal order of polynomial are determined based on test data. Results show that this model is effective in estimating the reliability of rotary lip seals and can achieve a better goodness of fit.

UAV navigation in high dynamic environments:A deep reinforcement learning approach

Unmanned Aerial Vehicle(UAV) navigation is aimed at guiding a UAV to the desired destinations along a collision-free and efficient path without human interventions, and it plays a crucial role in autonomous missions in harsh environments. The recently emerging Deep Reinforcement Learning(DRL) methods have shown promise for addressing the UAV navigation problem,but most of these methods cannot converge due to the massive amounts of interactive data when a UAV is navigating in high dynamic environments, where there are numerous obstacles moving fast.In this work, we propose an improved DRL-based method to tackle these fundamental limitations.To be specific, we develop a distributed DRL framework to decompose the UAV navigation task into two simpler sub-tasks, each of which is solved through the designed Long Short-Term Memory(LSTM) based DRL network by using only part of the interactive data. Furthermore, a clipped DRL loss function is proposed to closely stack the two sub-solutions into one integral for the UAV navigation problem. Extensive simulation results are provided to corroborate the superiority of the proposed method in terms of the convergence and effectiveness compared with those of the state-of-the-art DRL methods.

Anisotropic nanocomposite hydrogels with enhanced actuating performance through aligned polymer networks

Anisotropic composite hydrogels have wide applications in the fields of materials for actuators and sensors.Herein,we report an anisotropic composite hydrogel prepared by a mechanical-strain-induced method.Polymer networks including poly(N-isopropylacrylamide)(PNIPAM)and sodium alginate(SA),as well as carbon nanotubes(CNTs)are found to align simultaneously by stretching,and then fixed by physical crosslinking through non-covalent bonds.Composite hydrogels with doubly aligned polymer networks showed anisotropic optical and mechanical properties.The actuation performance of the anisotropic composite hydrogels as compared with the isotropic ones was found to be enhanced,which showed the capability of lifting 100 times its weight with 20%contraction strain.Besides,a bilayer hydrogel was designed to bend with a maximum of 390°to mimic the tendril behavior of plants.

Magnetic-programmable organohydrogels with reconfigurable network for mechanical homeostasis

Synthetic materials with tunable mechanical properties have great potential in soft robotics and biomedical engineering.However,current materials are limited to the mechanical duality altering their mechanical properties only between soft and hard states and lack of consecutively programmable mechanics.Herein,the magnetic-programmable organohydrogels with heterogeneous dynamic architecture are designed by encasing oleophilic ferrofluid droplets into hydrogel matrix.As magnetic field increases,the mechanical properties of organohydrogels can be consecutively modulated owing to the gradual formation of chain-like assembly structures of nanoparticles.The storage modulus G'increases by 2.5 times when magnetic field goes up to 0.35 T.Small-Angle X-ray Scattering(SAXS)confirms the reconfigurable orientation of nanoparticles and the organohydrogels show reversible modulus switching.Besides,the materials also exhibit high stretchability,magnetic actuation behavior and effective self-healing capability.Furthermore,the organohydrogels are applied into the design of effectors with mechanical adaptivity.When subjected to serious external perturbations,the effector can maintain mechanical homeostasis by regulating modulus of organohydrogel under applied magnetic field.Such materials are applicable to homeostatic systems with mechanically adaptive behaviors and programmed responses to external force stimuli.