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991.
为解决阵列勘探在现场铺设时,采集节点地址容易发生错乱的问题,提出了一种"流水线逐级增长"与"双次对比"相结合的动态分配方法,以实现在任何现场铺设条件下均能有序地设置所有采集节点的地址。基于阵列勘探的结构特点,使各个采集节点的地址以流水线的方式在同一时间内同时增加,从而实现采集节点地址的并行快速设置,缩短系统初始化的时间。同时采用对每个采集节点的地址进行两次对比设置的方法,提高节点地址被正确设置的可靠性。搭建了具有8个采集节点的实验系统,结果表明8个节点地址设置总时间为162.55 s,与理论分析一致,同时也证明了该方法的有效性。  相似文献   
992.
张杰  江涛  张怀根  章宏 《现代雷达》2019,41(6):13-18
在分析雷达及其对抗技术发展现状的基础上,阐述了雷达系统射频隐身技术的概念及其重要性;通过对射频隐身基本原理的研究,提出从雷达射频辐射的时、频、空和能等多维空间上进行控制,并与作战环境相融合等研究方向与方法,为开展具有隐身性能的雷达装备研制和技术研究提供参考。  相似文献   
993.
朱宏  孙磊  王真  邓学宾  采峰 《现代雷达》2019,41(9):66-70
针对相控阵雷达天线阵面设计过程不精细、数据追溯困难、需求分析不充分等问题,运用系统工程和六西格玛设计方法,开展相控阵雷达天线阵面的设计流程的优化,精细化地展开设计活动,建立模板表单,优化设计过程和设计规范,并在相控阵雷达天线阵面的研制中完成流程验证,提升了设计质量和降低研制风险。  相似文献   
994.
Rational design of promising electrolyte is considered as an effective strategy to improve the cycling stability of lithium metal batteries (LMBs). Here, an elaborately designed ionic liquid-based electrolyte is proposed that is composed of lithium bis(trifluoromethanesulfonyl)imide as the lithium salt, 1-ethyl-3-methylimidazolium nitrate ionic liquid ([EMIm][NO3] IL) and fluoroethylene carbonate (FEC) as the functional solvents, and 1,2-dimethoxyethane (DME) as the diluent solvent. Using [EMIm][NO3] IL as the solvent component facilitates a special Li+-coordinated NO3 solvation structure, which enables the continues electrochemical reduction of solvated NO3 and the formation of remarkably stable and conductive solid electrolyte interface. With FEC as another functional solvent and DME as the diluent solvent, the formulated electrolyte delivers high oxidative stability and ionic conductivity, and endows improved electrochemical reaction kinetics. Therefore, the formulated electrolyte demonstrates exceedingly reversible and stable Li stripping/plating behavior with high average Coulombic efficiency (98.8%) and ultralong cycling stability (3500 h). Notably, the high-voltage Li|LiNi0.8Co0.1Mn0.1O2 full cell with IL-based electrolyte exhibits enhanced cyclability with a capacity retention of 65% after 200 cycles under harsh conditions of low negative/positive ratio (3.1) and lean electrolyte (2.5 µL mg−1). This study creates the first NO3-based ionic liquid electrolyte and evokes the avenue for practical high-voltage LMBs.  相似文献   
995.
Nex-generation high-energy-density storage battery, assembled with lithium (Li)-metal anode and nickel-rich cathode, puts forward urgent demand for advanced electrolytes that simultaneously possess high security, wide electrochemical window, and good compatibility with electrode materials. Herein an intrinsically nonflammable electrolyte is designed by using 1 M lithium difluoro(oxalato)borate (LiDFOB) in triethyl phosphate (TEP) and N-methyl-N-propyl-pyrrolidinium bis(trifluoromethylsulfonyl)imide [Pyr13][TFSI] ionic liquid (IL) solvents. The introduction of IL can bring plentiful organic cations and anions, which provides a cation shielding effect and regulates the Li+ solvation structure with plentiful Li+-DFOB and Li+-TFSI complexes. The unique Li+ solvation structure can induce stable anion-derived electrolyte/electrode interphases, which effectively inhibit Li dendrite growth and suppress side reactions between TEP and electrodes. Therefore, the LiNi0.9Co0.05Mn0.05O2 (NCM90)/Li coin cell with this electrolyte can deliver stable cycling even under 4.5 V and 60 °C. Moreover, a Li-metal battery with thick NCM90 cathode (≈ 15 mg cm−2) and thin Li-metal anode (≈ 50 µm) (N/P ≈ 3), also reveals stable cycling performance under 4.4 V. And a 2.2 Ah NCM90/Li pouch cell can simultaneously possess prominent safety with stably passing the nail penetration test, and high gravimetric energy density of 470 Wh kg−1 at 4.4 V.  相似文献   
996.
The performance of alkaline fuel cells is severely limited by substandard anion exchange membranes (AEMs) due to the lower ionic conductivity compared to the proton exchange membranes. The ionic conductivity of AEMs can be effectively improved by regulating the microphase structure, but it still cannot meet the practical use requirements. Here, enhanced microphase-separated structures are constructed by the cooperativity of highly hydrophilic dual cations and highly hydrophobic fluorinated side chains. Meanwhile, the introduction of  O enhances the flexibility of side chains and facilitates the formation of ion transport channels. The dual piperidinium cation functionalized membrane (PB2Pip-5C8F) which is grafted with the ultra-hydrophobic fluorocarbon chain exhibits a high conductivity of 74.4 mS cm−1 at 30 °C and 168.46 mS cm−1 at 80 °C. Furthermore, the PB2Pip-5C8F membrane achieves the highest peak power density of 718 mW cm−2 at 80 °C under a current density of 1197 mA cm−2 without back pressure. A long-term life cell test of this AEM shows a low voltage decay rate of 1.68 mV h−1 over 70 h of operation at 80 °C.  相似文献   
997.
With the advancement of medical and digital technologies, smart skin adhesive patches have emerged as a key player for complex medical purposes. In particular, skin adhesive patches with integrated electronics have created an excellent platform for monitoring health conditions and intelligent medication. However, the efficient design of the adhesive patches is still challenging as it requires a strong combination of network structure, adhesion, physical properties, and biocompatibility. To design an assimilated device, one must have a deep knowledge of various skin adhesive patches. This article provides a comprehensive review of the recent advances in skin-adhesive patches, including hydrogel-based adhesive patches, transdermal patches, and electronic skin (E-skin) patches, for various biomedical applications such as wound healing, drug delivery, biosensing, and health monitoring. Furthermore, the key challenges, implementable strategies, and future designs that can potentially provide researchers in designing innovative multipurpose smart skin patches are discussed. These advanced approaches are promising for managing the health and fitness of patients who require regular medical care.  相似文献   
998.
In recent years, although light-driven soft actuators have attracted intense scientific attention and achieved remarkable progress, the design and construction of an intelligent robotic system with maneuverability, self-adaptability, untethered control, and greater freedom of action, in particular the omnidirectional motion capability on a plane, remains challenging. Herein, four types of photo-thermal fillers and an unprecedented twist-bend actuation mode is introduced into a liquid crystal elastomer-based soft robot. The obtained twist-bend crawling robot not only exhibits in situ rotation, four-way turning, and four-way linear motion under light irradiation with four wavelength bands (520, 655, 808, and 980 nm), but also demonstrates the ability to avoid obstacles in complex geographical environments. This work may bring a new perspective for fabrication and development of soft robots that can adapt to dynamic and complex environmental conditions.  相似文献   
999.
Herein, a novel D4 symmetrical redox-active ligand tetrathia[8]circulene-2,3,5,6,8,9,11,12-octaol (8OH-TTC) is designed and synthesized, which coordinates with Ni2+ ions to construct a 2D conductive metal-organic framework (2D c-MOF) named Ni-TTC. Ni-TTC exhibits typical semiconducting properties with electrical conductivity up to ≈1.0 S m−1 at 298 K. Furthermore, magnetism measurements show the paramagnetic property of Ni-TTC with strong antiferromagnetic coupling due to the presence of semiquinone ligand radicals and Ni2+ sites. In virtue of its decent electrical conductivity and good redox activity, the gravimetric capacitance of Ni-TTC is up to 249 F g−1 at a discharge rate of 0.2 A g−1, which demonstrates the potential of tetrathia[8]circulene-based redox-active 2D c-MOFs in energy storage applications.  相似文献   
1000.
A novel algorithmic method, based on the different stress distribution on the surface of thin film in an SOI microstructure, is put forward to calculate the value of the silicon piezoresistance on the sensitive film. In the proposed method, we take the Ritz method as an initial theoretical model to calculate the rate of piezoresistance ΔR/R through an integral (the closed area Ω where the surface piezoresistance of the film lies as the integral area and the product of stress σ and piezoresistive coefficient π as the integral object) and compare the theoretical values with the experimental results. Compared with the traditional method, this novel calculation method is more accurate when applied to calculating the value of the silicon piezoresistance on the sensitive film of an SOI pieoresistive pressure sensor.  相似文献   
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