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111.
《Current Applied Physics》2015,15(9):1005-1009
Forming-free and self-compliant bipolar resistive switching is observed in Cu/TaOx/TiN conductive bridge random access memory. Generally, Pt has been investigated as an inert electrode. However, Pt is not desirable material in current semiconductor industry for mass production. In this study, all electrodes are adapted to complementary metal-oxide-semiconductor compatible materials. The self-compliant resistive switching is achieved via usage of TiN bottom electrode. Also, dissolved Cu ions in TaOx lead to forming-free resistive switching behavior. The resistive switching mechanism is formation and rupture of combined oxygen vacancy/metallic copper conductive filament. We propose that Cu/TaOx/TiN is a promising candidate for a conductive bridge random access memory structure. 相似文献
112.
113.
Simultaneous determination of peroxydisulfate and conventional inorganic anions by ion chromatography with the column‐switching technique
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Zhongping Huang Chengzhu Ni Fengli Wang Zuoyi Zhu Qamar Subhani Muhua Wang Yan Zhu 《Journal of separation science》2014,37(3):198-203
The application of ion chromatography with the column‐switching technique for the simultaneous analysis of peroxydisulfate and conventional inorganic anions in a single run is described. With this method, conventional inorganic anions were separated by consecutive elution through both the guard column and separation column, but peroxydisulfate that only passed through the guard column had a good peak shape and short retention time. A series of standard solutions consisting of target anions of various concentrations from 0.01 to 75 mg/L were analyzed, with a correlation coefficient (r) ≥ 0.9990. The limits of detection were in the range of 0.49–9.84 μg/L based on the S/N of 3 and a 25 μL injection volume. RSDs for retention time, peak area, and peak height were all <1.77%. A spiking study was performed with satisfactory recoveries between 97.6 and 103.4% for all anions. The quantitative determination of peroxydisulfate and conventional inorganic anions in surface waters was accomplished within 18 min by this column‐switching technique. 相似文献
114.
Polymer network liquid crystal (PNLC) spatial light modulators are attractive for display and photonic applications because they can achieve submillisecond response time while keeping a large phase change. However, their on-state scattering caused by the grain boundary of LC multidomains hinders their applications. In this article, we review recent progress on the development of scattering-free PNLCs extending from short-wavelength infrared to visible region by reducing the domain sizes to ∼200 nm through low temperature curing process. To reduce operation voltage, both transmissive and reflective modes, LC material properties (birefringence and dielectric anisotropy), polymer composition and concentration, and pretilt angle effect are analyzed. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014 , 52, 183–192 相似文献
115.
Da‐Wei Fu Ji‐Xing Gao Wen‐Hui He Xue‐Qin Huang Yu‐Hua Liu Yong Ai 《Angewandte Chemie (International ed. in English)》2020,59(40):17477-17481
1,4‐Diazabicyclo[2.2.2]octane (dabco) and its derivatives have been extensively utilized as building units of excellent molecular ferroelectrics for decades. However, the homochiral dabco‐based ferroelectric remains a blank. Herein, by adding a methyl (Me) group accompanied by the introduction of homochirality to the [H2dabco]2+ in the non‐ferroelectric [H2dabco][TFSA]2 (TFSA=bis(trifluoromethylsulfonyl)ammonium), we successfully designed enantiomeric ferroelectrics [R and S‐2‐Me‐H2dabco][TFSA]2. The two enantiomers show two sequential phase transitions with transition temperature (Tc) as high as 405.8 K and 415.8 K, which is outstanding in both dabco‐based ferroelectrics and homochiral ferroelectrics. To our knowledge, [R and S‐2‐Me‐H2dabco][TFSA]2 are the first examples of dabco‐based homochiral ferroelectrics. This finding opens an avenue to construct dabco‐based homochiral ferroelectrics and will inspire the exploration of more eminent enantiomeric molecular ferroelectrics. 相似文献
116.
A fault-tolerant high-performance SElf-Routing 2 × 2 Optical ATM Switch (SEROS) is proposed. The switch is designed using all-optical components which allows the exploitation of spatial parallelism. SEROS can be used with any multistage interconnection network such as Omega, Banyan, Shuffle or Benes. For the purpose of this study, SEROS has been incorporated into a generic self-routing multistage interconnection network that uses 2 × 2 switches and is not fault tolerant. Reliability analysis is carried out and the results are compared with two major fault-tolerant networks. They show that without redundant switches, better network survivability is achieved. All the switches in the network are 2 × 2, making it easier to mass produce. 相似文献
117.
分析了软交换向IMS演进存在的问题,从安全性及QoS角度讨论了下一代网络的构建,并分析了IPv6协议的不足之处和中国电信业需要考虑的几个关键问题. 相似文献
118.
聂世刚 《电子产品可靠性与环境试验》2006,24(2):21-25
对加固计算机用开关电源的可靠性设计进行了系统的探讨。结合开关电源的原理.对影响其可靠性的因素和元器件的选用原则进行了阐述,着重分析了加固计算机用开关电源的可靠性设计:电应力设计、保护电路设计、热设计、电磁兼容性设计、安全性设计和三防设计。其目的在于提高加固计算机用开关电源的可靠性。 相似文献
119.
对于某些由开关操作数得出喀呖声率的被测设备,目前大部分检测实验室的断续骚扰分析仪可能会漏计算一些开关操作。解释了标准中"开关操作"的定义,通过实际案例阐述了使用分析仪进行断续骚扰项目检测时,预置电流阀值的选择对检测结果的影响。 相似文献
120.