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91.
一种热塑态真空振动装药工艺   总被引:1,自引:0,他引:1       下载免费PDF全文
为提高弹药产品质量及生产过程的本质安全度,改善现有热塑态装药生产条件,针对常规热塑态装药方法存在的缺陷,提出一种将真空振动装药法引入热塑态装药工艺设备的设计方案。综合应用自动控制技术、大型真空室振动装药技术,实现了对弹药产品热塑态装药过程的自动控制,建立了热塑态装药生产线,并在某产品试制中得到成功应用。实践证明:该生产线提高了弹药装药质量和本质安全度,具有较高的经济效益和社会效益。  相似文献   
92.
在危险系数较高的救援、勘察或补给等重要任务中,为避免人员伤亡,需要无人车具备自主探索并协同到达多个目标位置的能力.基于此,提出一种基于多智能体强化学习的无人车分布式路径规划模型,通过集中训练方式生成无人车的行驶策略.仿真结果证明了该方法的有效性.  相似文献   
93.
Layered materials have received extensive attention for widespread applications such as energy storage and conversion, catalysis, and ion transport owing to their fast ion diffusion, exfoliative feature, superior mechanical flexibility, tunable bandgap structure, etc. The presence of large interlayer space between each layer enhances intercalation of the guest ion or molecule, which is beneficial for fast ion diffusion and charge transport along the channels. This intercalation reaction of layered compounds with guest species results in material with improved mechanical and electronic properties for efficient energy storage and conversion, catalysis, ion transport, and other applications. This review extensively discusses the intercalation of guest ionic or molecular species into layered materials used for various types of applications. It assesses the intercalation strategies, mechanism of ionic or molecular intercalation reactions, and highlights recent advancements. The electrochemical performances of several typical intercalated materials in batteries, supercapacitors, and electrocatalytic systems have been thoroughly discussed. Moreover, the challenges in the design and intercalation of layered materials, as well as prospects of future development are highlighted.  相似文献   
94.
2D materials and the associated heterostructures define an ideal material platform for investigating physical and chemical properties, and exhibiting new functional applications in (opto)electronic devices, electrocatalysis, and energy storage. 2D transition metal dichalcogenides (2D TMDs), as a member of the 2D materials family including 2D semiconducting TMDs (s-TMDs) and 2D metallic/semimetallic TMDs (m-TMDs) have attracted considerable attention in the scientific community. Over the past decade, the 2D s-TMDs have been extensively researched and reviewed elsewhere. Because of their distinctive physical properties including intrinsic magnetism, charge-density-wave order and superconductivity, and potential applications, such as high-performance electronic devices, catalysis, and as metal electrode contacts, 2D m-TMDs have grabbed widespread attention in recent years. However, reviews demonstrating the m-TMDs systematically and comprehensively have been rarely reported. Here, the recent advances in 2D m-TMDs in the aspects of their unique structures, synthetic approaches, distinctive physical properties, and functional applications are highlighted. Finally, the current challenges and perspectives are discussed.  相似文献   
95.
Gallium nitride (GaN)-based high-electron mobility transistors (HEMTs) are widely used in high power and high frequency application fields,due to the outstanding physical and chemical properties of the GaN material.However,GaN HEMTs suffer from degradations and even failures during practical applications,making physical analyses of post-failure devices extremely significant for reliability improvements and further device optimizations.In this paper,common physical characterization techniques for post failure analyses are introduced,several failure mechanisms and corresponding failure phenomena are reviewed and summarized,and finally device optimization methods are discussed.  相似文献   
96.
97.
Conducting polymer hydrogels are widely used as strain sensors in light of their distinct skin-like softness, strain sensitivity, and environmental adaptiveness in the fields of wearable devices, soft robots, and human-machine interface. However, the mechanical and electrical properties of existing conducting polymer hydrogels, especially fatigue-resistance and sensing robustness during long-term application, are unsatisfactory, which severely hamper their practical utilities. Herein, a strategy to fabricate conducting polymer hydrogels with anisotropic structures and mechanics is presented through a combined freeze-casting and salting-out process. The as-fabricated conducting polymer hydrogels exhibit high fatigue threshold (>300 J m−2), low Young's modulus (≈100 kPa), as well as long-term strain sensing robustness (over 10 000 cycles). Such superior performance enables their application as strain sensors to monitor the real-time movement of underwater robotics. The design and fabrication strategy for conducting polymer hydrogels reported in this study may open up an enticing avenue for functional soft materials in soft electronics and robotics.  相似文献   
98.
Developing new polymerized small molecular acceptor (PSMA) is pivotal for improving the performance of all-polymer solar cells. On the basis of this newly developed CH-series small molecule acceptors, two PSMAs are reported herein (namely PZC16 and PZC17, respectively). To reduce the molecular torsion caused by the traditional aromatic π-bridges, non-aromatic conjugated units (ethynyl for PZC16 and vinylene for PZC17) are adopted as the linkers and their effect on the photo-physical properties as well as the device performance are systematically investigated. Both polymer acceptors exhibit co-planar molecular conformation, along with broad absorption ranges and suitable energy levels. In comparison with the PM6:PZC16 film, the PM6:PZC17 film exhibits more uniform phase separation in morphology with a distinct bi-continuous network and better crystallinity. The PM6:PZC17-binary-based devices exhibit a satisfactory PCE of 16.33%, significantly higher than 9.22% of the PZC16-based devices. Impressively, PM6:PZC17-based large area device (ca. 1 cm2) achieves an excellent PCE of 15.14%, which is among the top performance for reported all-polymer solar cells (all-PSCs).  相似文献   
99.
甜菜多倍体新品种狼甜301由四倍体双丰1号与二倍体工农5号系统中的9×9品系杂交育成,属于抗逆性强、抗褐斑病性强的高糖型多位多倍作品种。该品种在内蒙古自治区甜菜品种区域试验及生产试验中其平均块根产量,含糖率和产糖量分别比对照品种工农5号提高3.7%~14.2%、1.32%~3.0%和12.3%~40.9%。褐斑病发病级数比对照低1.5~2.5级,具备较强的杂种优势、适应性广。该品种1995年由内蒙古自治区农作物品种审定委员会审定命名为“狼甜301”,1995年4月通过了中国轻工总会甜菜糖业研究所品种审定委员会的审定,命名为中甜──狼甜301。  相似文献   
100.
Studies have shown that the thermoelectric properties of CoSb3 could be improved by the substitution of group IVB or VIB elements for Sb. However, the substitution volume is limited. To get a better picture of the substitution volume in view of thermoelectric properties, Ge and Te double-substituted skutterudite materials were prepared with the nominal composition of Co4Sb x Ge5.9−0.5x Te6.1−0.5x (x = 11, 10, 9, 8) by the traditional solid-state reaction method and spark plasma sintering, and Rietveld analysis was employed to refine the crystal structure. The results showed that the lattice parameter decreased linearly and the solubility limitations of group IVB and VIB elements were greatly alleviated by the Ge and Te codoping. Besides, the thermoelectric properties were analyzed through measurements of electrical and thermal conductivities as well as room-temperature electrical transport properties. The results showed that the substitution volume of Ge and Te could play an important role in the thermoelectric properties, and a minimum lattice thermal conductivity value of 1.56 W m−1 K−1 was obtained at around 673 K for Co4Sb8Ge1.9Te2.1. Co4Sb11Ge0.4Te0.6 achieved the best figure of merit of 0.89 at around 773 K, which was remarkably improved over that of untreated CoSb3.  相似文献   
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