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61.
The limits posed by physics to the quantity of information that can be transmitted with a certain amount of power are investigated. The same ultimate limits are found for transmission of information encoded using matter and massless fields. 相似文献
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It is argued that the partition of a quantum system into subsystems is dictated by the set of operationally accessible interactions and measurements. The emergence of a multipartite tensor product structure of the state space and the associated notion of quantum entanglement are then relative and observable induced. We develop a general algebraic framework aimed to formalize this concept. 相似文献
64.
Lloyd S 《Physical review letters》2003,90(16):167902
A communication channel is a physical system that transfers information from one place to another. Examples of communication channels include wires, optical fibers, and chains of spins that propagate spin waves through a medium. This Letter shows that the power-limited communication capacity of a multimode optical fiber or a set of parallel spin chains can be enhanced by introducing nonlinear couplings between the modes or chains. In particular, M coupled, entangled modes can send M bits in the same time it takes a single mode to send a single bit, and in the same time it takes M uncoupled, unentangled modes to send sqrt[M] bits. 相似文献
65.
The 3-alkylidene-3H-indole 1-oxide functional group found in the naturally occurring alkaloid avrainvillamide has been synthesized by a cross coupling-reductive condensation sequence and found to undergo reversible addition of oxygen- and sulfur-based nucleophiles. 相似文献
66.
Petoud S Cohen SM Bünzli JC Raymond KN 《Journal of the American Chemical Society》2003,125(44):13324-13325
Efficient lanthanide (Ln) luminescent probes require good ligand-to-metal energy transfer and high aqueous stability. A family of ligands based on 2-hydroxyisophthalamide chelating units is reported. These form highly stable, eight-coordinate Ln complexes. Several of these (Ln = Sm, Eu, Tb, Dy) emit in the visible region with good ligand-to-lanthanide energy transfer. The absolute quantum yields of the two Tb complexes studies (Phi = 0.59, 0.61) and high absorbance make these the brightest luminescent probes for time-resolved detection; the emission spectrum of one complex can be seen down to 10-15 M. The low overlap of the four different Ln complexes enables their simultaneous detection and discrimination. 相似文献
67.
Shiming Zhang Yugeng Wen Weiyi Zhou Yunlong Guo Lanchao Ma Xingang Zhao Zhen Zhao Stephen Barlow Seth R. Marder Yunqi Liu Xiaowei Zhan 《Journal of polymer science. Part A, Polymer chemistry》2013,51(7):1550-1558
Solution‐processable polymers consisting of perylene diimide (PDI) acceptor moieties alternating with dithienothiophene (DTT), N‐dodecyl‐dithienopyrrole (DTP), or oligomers of these donor groups have been synthesized. We have, in addition to varying the donor, varied the N,N′ substituents of the PDIs. The thermal, optical, electrochemical, and charge‐transport properties of the polymers have been investigated. The polymers show broad absorption extending from 300 to 1000 nm with optical band gaps as low as 1.2 eV; the band gap decreases with increasing the conjugation length of donor block, or by replacement of DTT by DTP. The electron affinities of the polymers, estimated from electrochemical data, range from ?3.87 to ?4.01 eV and are slightly affected by the specific choice of donor moiety, while the estimated ionization potentials (?5.31 to ?5.92 eV) are more sensitive to the choice of donor. Bottom‐gate top‐contact organic field‐effect transistors based on the polymers generally exhibit n‐channel behavior with electron mobilities as high as 1.7 × 10–2 cm2/V/s and on/off ratios as high as 106; one PDI‐DTP polymer is an ambipolar transport material with electron mobility of 4 × 10–4 cm2/V/s and hole mobility of 4 × 10–5 cm2/V/s in air. There is considerable variation in the charge transport properties of the polymers with the chemical structures. © 2013 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 相似文献
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Seth E. Moody 《Fresenius' Journal of Analytical Chemistry》1907,46(12):777
Ohne Zusammenfassung 相似文献
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