Herein, a CuSe/MnSe2 heterostructure with Se vacancies is fabricated as an ultrafast anode for low-temperature sodium-ion batteries. It achieves 380.3 mAh g-1 after 1500 cycles (3.0 A g-1) and 403.6 mAh g-1 at -30 °C (0.5 A g-1), highlighting exceptional cyclability and low-temperature adaptability.

Due to the severe dendrite phenomenon, the large-scale application of sodium metal batteries (SMBs) is difficult. The fabrication of artificial inorganic/organic solid electrolyte interphases (SEI), incorporating the role of metallic sites in addressing the dendrite issue, has attracted great attention. This work reports the in-situ formation of inorganic/organic SEI and sodium affinity sites from antimony-doped zinc fluoride current collector (Sb-ZnF2@Zn). The resulting Sb-ZnF2@Zn/Na anodes exhibited dendrite-free sodium deposition, significantly enhanced electrochemical performance, and improved long-term stability by optimizing the interfacial composition and structure. Thanks to the formed inorganic/organic SEI and sodium affinity sites, the symmetrical cells displayed an extended cycle life of 2000 h at 6 mA cm- 2 with 3mAh cm- 2. This work not only improves the uniform infiltration of the electrolyte but also promotes the uniform transport of Na+, as validated by dynamic contact angle experiments and finite element calculations. The findings provide valuable insights into the design of advanced sodium metal anodes for next-generation SMBs.

Metal oxides have high theoretical capacities as anode materials for lithium-ion batteries, but the potential of most of them exceeds 1.0 V, which significantly hinders their practical application in full cells. Li4Ti5O12 (LTO) anode exhibits excellent cycling performance due to its "zero strain" characteristics. However, its theoretical capacity is only 175 mAh g-1, coupled with the high potential (1.55 V), it will lead to low energy density and low full-cell voltage. Here, we use a partial Zn substitution strategy to tune the potential of LTO to improve its electrochemical performance. LTO with optimal Zn substitution (ZT2) exhibits greatly enhanced battery performance with low working potential (0.62 V) and high capacity (238.4 mAh g-1 after 200 cycles at 2 A g- 1 ). The ultra-low potential of Zn-substituted ZT2 is due to the fact that the reaction process of Li+ intercalation has changed from mainly occurring at the 16c octahedral sites to occurring at the 8a site due to the addition of Zn. The specific energy density of the ZT2//LCO (LiCoO2) full cell is 96.9 Wh kg-1 , which is much higher than that of the LTO//LCO full cell. In addition, the ZT2//LCO full cell still maintains a high stability of 78.7 mAh g- 1 after 3500 cycles at a current density of 0.5 A g- 1 . Our results demonstrate that Zn-substituted LTO exhibits high capacity and low voltage advantages, indicating great significance for promoting the practical application of titanium-based anode materials.

Abstract Transition metal oxide (TMO)‐based anodes attract much attention for lithium storage due to the merits of high theoretical capacity, facile synthesis, and easy scale‐up. Moreover, the increased working potential avoids the issue of lithium dendrites formation and thus improves battery safety. Herein, we propose a route to significantly improve the electrochemical performance of TMO anodes through configurational entropy optimization. For example, high‐entropy oxide (FeCoNiCrCu)3O4 is synthesized by carefully selecting metal elements. The (FeCoNiCrCu)3O4 electrode ensures not only low potential but also holds high capacity. In the half‐cell configuration, the (FeCoNiCrCu)3O4 electrode provides a specific capacity of 575.7 mAh g−1 after 200 cycles at 0.2 A g−1. More importantly, the electrode showed a relatively low discharge voltage of 0.39 V at 0.5 A g−1, which is caused by the configuration entropy optimization. The assembled (FeCoNiCrCu)3O4//LCO coin‐type full cell exhibits a high capacity of 266.3 mAh g−1 after 100 cycles at 0.2 A g−1 and an operating voltage up to 3.9 V.

视觉解释方法是深度神经网络可解释领域的热门研究课题，但现有方法未能有效利用多层次决策信息导致视觉解释效果差。针对此问题，该文提出一种融合多层次决策信息的视觉解释方法。首先，挖掘特征图中高细粒度局部层次的决策信息生成一组与决策结果相关性强的加权特征图，采用定序分组方式对其合并，获取一组低冗余度掩码；随后，采取模糊边界和积分方法对掩码进行处理，基于全局层次的决策贡献并行计算分组掩码重要度分数，提高了算法对全局决策信息的敏感性和算法速度。最后，通过消融实验确定了算法的最优参数组合，并在ImageNet数据集上与现有的先进视觉解释方法进行了定性和定量比较。实验结果表明：该文方法通过结合多层次决策信息，在置信度测试和定位测试中取得了更好的视觉解释结果，且速度达到68ms。

随着作战需求和信息技术的发展,催生了具备侦察定位、精确打击、封锁干扰等各类功能的信息化炮弹,其效能的发挥通常需要弹载功能器/部件和弹体结构、材料能抗各种高过载作用,抗高过载技术已成为制约炮弹信息化、智能化快速发展的主要瓶颈技术之一.梳理了信息化炮弹抗高过载问题的发展历程,阐明了信息化炮弹抗高过载的本质内涵;总结了过载环境建模与测量、抗过载结构与材料、抗过载试验与测试等关键技术;提出了以功能防护为核心目标的抗高过载设计思路,明确了信息化炮弹抗高过载设计流程.提出的"本体强度加固、支撑体变形吸能、结构件破坏转移、前沿技术交叉"抗高过载方法在工程实践中取得了较好效果,为信息化炮弹及具有高过载特征的火箭弹、导弹等抗过载设计提供了参考.

弹载图像目标检测方法是实现图像自寻的弹药"发射后不管"、对目标进行自主打击的关键技术.弹药图像自寻的面临着成像环境恶劣,目标特性变化快,对算法体积、速度要求苛刻等问题.围绕弹载目标检测难点问题进行综述,将基于深度学习的目标检测方法区分为基于候选框、无候选框和基于transformer的方法,回顾了各类方法主要研究进展;对特征提取网络轻量化、预测特征图增强、非极大值抑制后处理算法、训练中样本均衡、模型压缩等弹载图像目标检测模型部署中的关键技术进行了梳理;对比了典型目标检测方法在ImageNet、COCO及弹载图像目标数据集上的性能,并对未来发展进行展望.

Nb2O5 -based nanomaterials are emerged as as a promising electrode material for lithium-ion batteries. However, a systematic investigation of its electrochemical performance was scarcely investigated. In this work, carbon coated Nb2O5 -nanosheets with different mass ratios of Nb2O5 to dopamine hydrochloride were synthesized and investigated their lithium- storage performance. The developed nanosheets were coexist in three phases of T- Nb2O5, H- Nb2O5 and M- Nb2O5 with different amount of oxygen vacancies and carbon contents. The effect of different carbon content on the electrochemical performance of Nb2O5 nanosheets were investigated. It is found that the Nb2O5 nanosheets (Nb2O5 @C-2) with carbon coating thickness about 6 nm displayed enhanced lithium storage capacity. The electrode delivers intial charge and discharge capacities of 327.4 mA h g-1 and 332.3 mA h g-1 respectively at 1C. Moreover, the electrode shows excellent cyclic stability and delivers reversible charge capacity of ~187.7 mAhg-1 at 5C after 700 cycles with a capacity retention rate of 97.1%. In addition, the electrode exhibits superior cycling performance and good rate capabitity as compare to other electrodes and previously reported composites. The ultrathin amorphous carbon layer plays an important role in improving the electrochemical performance of Nb2O5 due to increase in conductivity, surface area and stable structure of electrode material.

Carbonaceous materials are used as the anode for rechargeable lithium-ion batteries (LIBs), however, li-thium dendrites are easily formed during cycling due to the low lithium insertion potential (similar to 0.1 V versus Li+/Li). As alternative anodes, transition metal oxides based on conversion mechanism have attached much attention. But the high lithiation potential (> 1.0 V vs. Li+/Li) usually leads to a low output voltage and energy density when used in a full cell configuration. Herein, Zn-substituted Co3O4 submicron spheres are successfully synthesized by a facile solvothermal reaction and subsequent calcination method. When used as the anode for LIB, the optimized sample shows a specific capacity of 686 mAh g(-1) at 0.8 A g(-1) after 500 cycles, and a specific capacity of 692.9 mAh g(-1) at a higher current density of 3.2 A g(-1) in a half-cell. Thanks to the controlled Zn substitution, the discharge voltage plateau is 0.16 V lower than that of the pure Co3O4 anode at a current density of 0.4 A g(-1). Further investigation of the 0.5Zn-Co3O4//LiCoO2 full cells also displays a high capacity (400.7 mAh g(-1) after 200 cycles at 0.4 A g(-1)) and an excellent rate capability (658.1 mAh g(-1) at 1.6 A g(-1)) compared with the Co3O4//LiCoO2 full cells. This work confirms that substituting suitable metal elements into sub-micron conversion based anodes can reduce the voltage plateau, which is of great significance for the practical applications in high performance energy storage devices. (C) 2021 Elsevier B.V. All rights reserved.

Molybdenum disulfide (MoS2) has become a very promising anode material due to its expandable interlayer spacing and high theoretical capacity. Herein, metallic phase MoS2 ultrathin nanosheets in-situ grown on chemically activated hollow carbon spheres (HCS) are synthesized. The 3D conductive structures not only improve the conductivity and shorten the ion diffusion path, but also buffer the volume expansion and avoid the agglomeration of the MoS2 nanosheets. Due to the above advantages, this composite electrode shows considerable storage characteristics. When used as the anode for SIBs, the discharge capacity is 296.2 mA h g−1 at a current density of 0.1 A g−1 after 50 cycles. When used as the anode for PIBs, the discharge capacity reaches 287.8 mA h g−1 after 50 cycles at a current density of 0.1 A g−1. The current synthesis strategy provides an alternative route to develop high performance electrodes for sodium and potassium ions storage.

Nb2O5-based nanomaterials are emerged as a promising electrode material for lithium-ion batteries. However, the rapid capacity loss during cycling and poor rate capability limits their usage in practical applications. In this work, a novel strategy is employed to address these issues. Polymorphic Nb2O5 nanosheets with surface carbon modification were synthesized. The developed nanosheets were coexist in orthorhombic (T), tetragonal (M) and monoclinic (H) phases with abundant interfaces and tunable amount of carbon contents. The combined effect of surface carbon coating along with coexistence of multiphases on the electrochemical performance of Nb2O5 nanosheets were investigated. It is found that the Nb2O5 nanosheets (Nb2O5 @C-2) with carbon coating thickness of 6 nm delivers enhanced reversible capacity (similar to 187.7 mAh.g(-1) at 5C with a capacity retention rate of 97.1 %.), outstanding rate capability (116.8 mAh.g(-1) at 35C as compare to many states of art Nb2O5-based anode materials) and good cycling stability even after 700 cycles. The excellent performance of the Nb2O5@C-2 electrode owed to the synergy between Nb2O5 and ultrathin amorphous carbon layer with multiphases, creation of abundant interfaces, increase in ionic conductivity and stable structure. It is suggested that the lithium storage capabilities of Nb2O5 can be tuned by optimizing the thickness of carbon layer. (C) 2022 Elsevier B.V. All rights reserved.

The development of a reliable non-enzymatic multi-analyte biosensor is remained a great challenge for biomedical and industrial applications. In this prospective, rationally designed electrode materials having voltage switchable electrocatalytic properties are highly promising. Here, we report vanadium doped ZnO engineered nanostructures (Zn1-x V (x) O where 0 <= x <= 0.1) which exhibit voltage switchable electrocatalytic properties for accurate measurements of glucose and hydrogen peroxide. Microstructures and chemical analysis show that the oxygen vacancies in the material can be tuned by controlling the stoichiometric ratios which play key role for voltage dependent measurements of different analytes. The developed Zn1-x V (x) O nanostructures exhibit outstanding sensing ability for binary analytes with a high selectivity, low detection limit, thermal stability and long-term stability. The Zn0.9V0.1O/glassy carbon (GC) electrode shows 3-fold increase in reproducible sensitivity for both glucose (655.24 mu A mM(-1) cm(-2)) and H2O2 (13309.37 mu A mM(-1) cm(-2)) as compared to the pristine ZnO/GC electrode. Moreover, the electrode also shows good response for human blood serum and commercially available samples. The results demonstrate that defect engineering is a promising route for the development of cost-effective non-enzymatic multi-analyte sensors for practical applications.

Niobium pentoxide (Nb2O5) material is a promising anode for lithium-ion batteries (LIBs) due to the outstanding cycle performance and rate capability. However, the relatively low capacity severely limits the comprehensive performance. Generally, nanoscale engineering of the morphology and chemical composition of Nb2O5 anodes is employed to improve electrochemical lithium storage. In this work, we promote the reservable capacity of a sheetlike Nb2O5 anode by designing nanoscale phase interfaces between the nanodomains of T-Nb2O5, M-Nb2O5, and H-Nb2O5 phases, which are generated by good control over the calcination of Nb3O7F precursor at high temperatures. Microstructural and chemical analyses show that the sample calcined at 750 degrees C (Nb2O5-750) has optimized structural advantages to efficiently store lithium ions. When evaluated as anodes for LIBs, the Nb2O5-750 sample shows excellent lithium storage properties. In specific, the Nb2O5-750 electrode delivers a reversible capacity of 270.4 mAh g(-1) at 1C after 200 cycles. At a high rate of 5C, the Nb2O5-750 electrode has a reversible capacity of 174 mAh g(-1) after 800 cycles. This work provides an alternative way to improve the ion storage in the electrodes with intrinsic polymorphic structures.

Co9S8nanoparticles coated with N-doped few-layer graphene show improved electrocatalytic hydrogen evolution and sodium storage performance.

The synthesis of one-dimensional heterostructures having high dielectric constant and low dielectric loss has remained a great challenge. Until now, the dielectric performance of ZnO-ZnS heterostructures was scarcely investigated. In this work, large-scale ZnO-ZnS heterostructures were synthesized by employing the chemical vapor deposition method. High resolution transmission electron microscopy (HRTEM) confirms the formation of heterostructures. X-ray photoelectron spectroscopy (XPS) shows that S atoms fill up the oxygen vacancy (VO) in ZnO, leading to the suppression of charge carrier's movement from ZnO to ZnS; instead there is charge transfer from ZnS to ZnO. Conductivity mismatch between adjacent ZnO and ZnS materials leads to the accumulation of free charges at the interface of the heterostructure and can be considered as a capacitor-like structure. The electrical behaviors of the potential phases of ZnO, ZnS and the ZnO-ZnS heterostructure are well interpreted by a best fitted equivalent circuit model. Each heterostructure acts as a polarization node with a specific flip-flop frequency and all such nodes form continuous transmission of polarization, which jointly increase the dielectric energy-storage performance. The orientational polarization of the polarons and Zn2+-VO dipoles present at the heterostructure interface contributes to the frequency stable dielectric constant at ≥103 Hz. Our findings provide a systematic approach to tailor the electronic transport and dielectric properties at the interface of the heterostructure. We suggest that this approach can be extended for improving the energy harvesting, transformation and storage capabilities of the nanostructures for the development of high-performance energy-storage devices.

舰炮武器系统以其高效费比、高射速、大载弹量等特点,在现代海战领域依旧发挥着不可替代的关键作用.基于国内外舰炮弹药发展现状,结合现代海战领域作战特点,总结了制约舰炮弹药发展的瓶颈问题.从作战任务需求和工程研制实际出发,从作战样式和技术实现两个方面论证了发展舰炮智能弹药的必要性,并指出其应具备的基本特征.充分借鉴发扬陆军制导炮弹成熟经验,提出了舰炮智能弹药四个关键技术研究方向.展望了舰炮武器系统未来发展,提出了大力发展大口径、远射程、高精度,兼具侦察、压制、干扰、封锁等能力的舰炮弹药系列的建议,为舰炮弹药的发展论证和设计研制提供了一些帮助.

This work addresses the effective jamming style of projectile-carried communication for frequency hopping radio with different modulation by applying simulation verification via OPNET platform to construct the projectile-carried communication jamming system model. A general projectile-carried communication jamming style based on the signal combination of sweep saw-tooth wave and noise frequency modulation is proposed and analyzed. The network model of projectile-carried communication jamming system is constructed, and then the model building process of frequency hopping radio from the two aspects of transmitter model and receiver model is deeply elaborated. We demonstrate that the general projectile-carried communication jamming style has good jamming effect on the frequency hopping radio receivers with five modulation modes of 2FSK, 2PSK, 2DPSK, MSK and GMSK by comparing the simulation results, including receiving throughput, end-to-end delay, time delay of wireless channel access, delivery rate of synchronized header message, signal-to-noise ratio, bit error rate, packet loss rate, remaining power of jammer. Among them, the bit error rate of radio receiver with five modulation modes is more than 20%.

The development of a highly sensitive and selective electrocatalyst for the detection of diclofenac sodium (D.S.) has remained a great challenge. In this work, graphene oxide functionalized with silver nanoparticles and zinc oxide (Ag–ZnO–GO) electrocatalyst was developed and investigated for the detection of D.S. The Ag–ZnO–GO/glassy carbon electrode exhibits high sensitivity and fast response within 3[Formula: see text]s owing to the efficient oxidation of D.S. at a very low potential at 0.25[Formula: see text]V. Moreover, the electrode shows a low detection limit of 0.02[Formula: see text][Formula: see text]M ([Formula: see text]) and long-term stability. To explore the synergic effects, the measurements of D.S. using GO, ZnO and ZnO–GO modified electrodes were also performed. The results demonstrate that the Ag–ZnO–GO nanocomposite electrode exhibits enhanced sensitivity and selectivity compared to the other electrodes. In addition, the electrode reveals excellent results for D.S. detection in the real samples as well. The enhanced performance of the proposed electrode is attributed to the improved electron transfer ability and synergic effects of the plasmonic Ag NPs and ZnO–GO structure. It is expected that Ag–ZnO–GO composite is a promising candidate for the construction of cost-effective electrochemical biosensors for medical and industrial applications.

The development of a highly sensitive and selective non-enzymatic electrode catalyst for the detection of a target molecule was remained a great challenge. In this regard, bimetallic nanowires (BMNWs) are considered as promising electrode material for their fascinating physical/chemical properties superior to a single system. In this article, nickel cobalt (Ni x –Co) BMNWs with tunable stoichiometry were prepared by a template assisted electrodeposition method and their catalytic performance was investigated for the detection of hydrogen peroxide (H2O2). It has been found that Ni–Co (0.5:1) BMNWs/PC electrode exhibits superior non-enzymatic sensing ability toward H2O2 detection with a high selectivity. The electrode shows fast response within ∼3 s and an excellent reproducible sensitivity of 2211.4 μAmM−1 cm−2, which is the best compared to the individual Ni, Co, Ni–Co (0.3:1) BMNWs and previously reported electrodes. In addition, the electrode shows a linear response in the wide concentration range from 0.005 mM to 9 mM, low detection limit of 0.5 μM (S/N = 3.2) and a relatively long-term storage (50 d). Moreover, the sensor reveals excellent results for H2O2 detection in the real samples. The enhanced sensitivity of the Ni–Co (0.5:1) BMNWs based electrode may be due to the stable structure and synergy of Ni and Co. The results demonstrate that the catalytic activity of the electrode binary catalyst towards H2O2 detection can be improved by adjusting the Ni/Co ratio in BMNWs. The excellent performance of the electrode suggests that Ni–Co BMNWs are promising candidate for the construction of cost-effective electrochemical sensors for medical and industrial applications.

Transition metal oxide (TMO) anodes show promising applications in energy storage due to the unique physical and chemical properties and high theoretical capacity to storage ions. Their practical usages are restricted by low intrinsic electronic conductivity, sluggish ionic diffusion, and large volume change during continuous cycling. In this work, we propose a strategy of selective solution-phase reduction on specific crystalline planes to generate the defect chemistry and thus improve the intrinsic electronic conductivity. Taking Co3O4 electrode as a typical example, we prepared the structures with different exposed planes, which were then subjected to solution-phase reduction at room temperature. When used as the electrodes for lithium ion batteries, the optimized material possesses a high reversible capacity of 873.5 mAh g(-1) at a current of 0.1 A g(-)(1), even at a large current density of 5 A g(-)(1), a remarkable discharge capacity of 569.1 mA h g(-1) can still be achieved. The improved performance is attributed to the synergistic effects of the optimized amount of Co2+ species and oxygen vacancies. The current strategy can be extended to other TMO electrodes, paving an alternative way to optimize the electrochemical performance for different applications. (C) 2020 Elsevier B.V. All rights reserved.