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101.
A new photochromic diarylethene derivative with a hydralazine unit was designed and synthesized. It was not only acted as a Zn2+ sensor with the fluorescent color change from dark blue to bright orange, but also acted as a fluorescent sensor for HSO4? with the fluorescent color change from dark blue to bright blue. Furthermore, the derivative also exhibits multi-addressable switching properties by the stimulations of lights and chemical reagents. Based on these characteristics, two combinational logic circuits were constructed with the emission intensity as the output signals, and the UV/vis lights, chemical species as the input signals. 相似文献
102.
103.
Xiaotong Chen 《Tetrahedron letters》2008,49(32):4697-4700
In this work, salicylaldehyde fluorescein hydrazone (1) was synthesized and characterized. Exhibiting reversible color changes responding to different pH in the presence of Cu(II) in buffered media, 1 could be applied as a colorimetric chemosensor for the detection of pH and Cu(II) bi-functionally. It presented a tunable system integrated with a Cu(II)-driven YES logic gate as well as an INHIBIT logic gate, with pH and Cu(II) as its chemical inputs based on encoding binary digits of logical conventions. 相似文献
104.
Magneto‐controlled OR, AND and INHIB logic gates were designed using cobalt ferrite magnetic nanoparticles (CoFe2O4, saturated magnetization ca. 70 emu g?1, 17±2 nm diameter) functionalized with microperoxidase‐11. Tunable magnetic field generated by three external permanent magnets (NdFeB) upon moving them below the electrochemical cell resulted in translocation of the biofunctionalized magnetic nanoparticles between conductive and nonconductive domains of a solid plate. This resulted in electrochemically readable output signals with the Boolean logic controlled by the magnetic input signals. The current corresponding to the reversible redox process of the heme measured at ?0.4 V (vs. SCE) was considered as “1” output signal, while a small background current obtained from the conducting interface in the absence of the magnetic nanoparticles was considered as “0” output signal. Addition of H2O2 to the solution resulted in the generation of a cathodic catalytic current when the microperoxidase‐11‐functionalized magnetic nanoparticles are associated with the conductive domain of the support. This resulted in the amplification of “1” output signal and the increased difference between “1” and “0” signals generated by the cell, thus reducing the possibility of errors in the Boolean logic operations. 相似文献
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106.
We explore the formation of Logic as an academic discipline and community in Russia before the revolution of 1917. In particular, we look at the various communication strategies that emerged within this community and its relations with the wider international scientific community. Interaction with Mathematics, which was undergoing its own “foundational revolution,” played a major role in the transition from archaic syllogistic to modern formal logic. We make extensive use of original sources, many of which have not been reprinted since their first publication. 相似文献
107.
Luigi Ingaliso 《Historia Mathematica》2011,38(2):232-247
The contributions made by the Italian mathematician Mario Pieri (1860-1913) are well known in the field of geometry. Pieri was a member of the School of Peano at the University of Turin. There he became engaged both by the problems of logic and by the philosophical aspects of Peano’s epistemology. This article was motivated by Pieri’s address given at the University of Catania, at the inauguration of the 1906-1907 academic year. My aim is to identify Pieri’s philosophical premises as found in his works and to present them in the general framework of the historical development of the Peano School. 相似文献
108.
错用罗素悖论-康托在集合论中的两个逻辑性错误 总被引:6,自引:0,他引:6
分析了罗素悖论与康托的实数集合不可数证明及康托定理S〈P(S)证明之间的本质性联系,发现康托的这两个非构造性证明与罗素悖论有完全相同的思路,但是康托犯了两个逻辑性错误而使他误用了这个悖论思路。得到明确的结论:康托在集合论中如上两个证明里的核心部分实际上是罗素悖论的翻版,这两个证明中的思路与做法是错误的,这样的证明结果没有科学性。 相似文献
109.
基于命题逻辑公式之间相似度的概念,在经典命题逻辑系统中提出了两种近似推理模式,得到了它们的一些基本性质。讨论了这两种推理模式与经典推理模式之间的关系。此外,当理论Γ有限时,本文分别给出Γ在α程度上近似推出公式A和理论Σ的充要条件。最后,我们给出公式A与有限理论Γ的结论集D(Γ)之间距离的计算公式。 相似文献
110.
格蕴涵代数中的滤子是格值逻辑推理中的一类重要代数结构.本文给出了利用格蕴涵代数的蕴涵运算表找出格蕴涵代数中所有滤子的方法.并举例说明该方法的有效性、可行性. 相似文献