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41.
42.
Jinghui Shen Baoshuai Liang Yu Dong Shiyu Feng Weiguo Huang 《Advanced functional materials》2023,33(28):2213341
Nonvolatile organic photonic transistor (OPT) memories have attracted widespread attention due to their nondestructive readout, remote controllability, and robust tunability. Developing electrets with similar molecular structures but different memory behaviors and light-responsive features is crucial for light-wavelength-modulated data encryption. However, reported OPT memories have yet to meet this challenge. Here a new electret molecule (“H-PDI”) is developed via reconfiguring the linear perylene diimide molecule (“L-PDI”) to a helical shape. Respectively incorporating H-PDI and L-PDI into the floating gate layer results to H-PDI OPT and L-PDI OPT. Attributing to their remarkably different electronic structures and energy bandgaps, H-PDI OPT and L-PDI OPT preferably respond to 405 and 532 nm light irradiation, respectively. Upon electrical programming, data can be written and stored in both memories with good retention features and a high “1”/“0” state current ratio over 105, though the data can only be erased by light with correct wavelengths, rather than the electrical field. Moreover, data stored in a memory array consisting of both H-PDI OPT and L-PDI OPT can only be read out by correct inputs, and wrong inputs will lead to highly deceptive outputs. This study provides a general design strategy of OPT for advanced data encryption and protection. 相似文献
43.
Songtao Ling Cheng Zhang Chunlan Ma Yang Li Qichun Zhang 《Advanced functional materials》2023,33(1):2208320
Confronted by the difficulties of the von Neumann bottleneck and memory wall, traditional computing systems are gradually inadequate for satisfying the demands of future data-intensive computing applications. Recently, memristors have emerged as promising candidates for advanced in-memory and neuromorphic computing, which pave one way for breaking through the dilemma of current computing architecture. Till now, varieties of functional materials have been developed for constructing high-performance memristors. Herein, the review focuses on the emerging 2D MXene materials-based memristors. First, the mainstream synthetic strategies and characterization methods of MXenes are introduced. Second, the different types of MXene-based memristive materials and their widely adopted switching mechanisms are overviewed. Third, the recent progress of MXene-based memristors for data storage, artificial synapses, neuromorphic computing, and logic circuits is comprehensively summarized. Finally, the challenges, development trends, and perspectives are discussed, aiming to provide guidelines for the preparation of novel MXene-based memristors and more engaging information technology applications. 相似文献
44.
R. L. Schafir 《Foundations of Physics Letters》1996,9(1):91-101
It is shown that nonlocality gives rise to an undecidable proposition, meaning it cannot be proved true nor proved false from the usual assumptions, but is independent of them. A variation on the usual thought experiment is considered in which the observers are timelike separated, but the nonlocality fails to become a precognition effect because of this independence result. 相似文献
45.
研制一种新型可移动式微量氧分析仪检定装置。该装置由标准气体、零点气、脱氧纯化器、减压阀、调节阀、4通阀、5通阀、不锈钢管路、流量控制系统、移动平台等组成。该装置气密性好,15 min内可将装置内氧气浓度由20.9%降至不大于0.1μmol/mol,对于0~10μmol/mol的微量氧分析仪检定结果的扩展不确定度为Urel=1.7%FS(k=2)。该装置满足气体标准物质的连续切换和在线检定的需要,检定时间短,结果准确可靠,可为在线式和非在线式微量氧分析仪的量值溯源提供有效保障。 相似文献
46.
Rafael Lucena 《Analytica chimica acta》2004,509(1):47-54
A multipurpose chamber capable of implementing a variety of continuous separation techniques is reported. The proposed module can be used in conjunction with flow manifolds coupled on-line to optical detectors in order to develop simple autoanalyzers for full sample pretreatment. The analytical applicability of such a device is discussed with specific regard to gas diffusion, dialysis, solid-phase extraction (SPE), and precipitation/dissolution techniques. Its versatility and simplicity are among the main advantages. Four different automated analyzers based on the use of the multipurpose chamber have been developed for monitoring of different quality control parameters of liquid food samples, namely, carbon dioxide in beer, ascorbic acid in fruit juice, caffeine in soft drinks and lactose, fat and protein in milk. The results obtained were compared with those provided by the existing alternatives for the same applications in terms of sensitivity and precision. 相似文献
47.
Tidjani Ngadi 《International journal of quantum chemistry》2003,94(2):65-74
In this article, we make a connection between the Rumer transformation, used in the study of the genetic code‐doublets, and the negation of classic logic. A unified classification is given, relying on two Klein's 4‐groups describing the symmetries of the 16 doublets of nitrogenous bases and those of the 16 binary connectives of classic logic, both groups being subgroups of a larger noncommutative group with eight elements we identify as the dihedral group D4. Also, some connections with other works are briefly considered. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2003 相似文献
48.
Summary The application of the O-FID Oxygenates Analyzer developed for the selective determination of oxygenated compounds in modern fuels has been studied for the identification and characterization of essential oils. In comparison to FID detection the O-FID technique results in a much simpler chromatogram. Because of the high selectivity for oxygenated compounds the O-FID method offers a fast and reliable quality control and positive identification of samples of different origin. Chromatograms obtained for lavender oils of different origin, natural and synthetic lemon oils and oils of bergamot respectively, as well as for camomilla oils are presented. 相似文献
49.
50.
三值双传输管电路的通用综合方法 总被引:1,自引:0,他引:1
提出采用双传管逻辑设计三值电路的方法,对每个MOS管的逻辑功能均采用传输运算予以表示以实现有效综合.建立了三值双传输管电路的反演法则和对偶法则.新提出的三值双传输管逻辑电路具有完全基于标准CMOS工艺,无需对MOS管作任何阈值调整,结构简单、规则,输入信号负载对称性好,逻辑摆幅完整以及无直流功耗等特点.采用TSMC 0.25μm工艺参数和最高电压为3V的HSPICE模拟结果验证了所提出综合方法的正确性. 相似文献