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61.
An Accurate Characterization of CRT Monitor (I) Verifications of Past Studies and Clarifications of Gamma 总被引:1,自引:0,他引:1
CRT monitors are widely used to view images on the Internet. The color images on the computer graphic display can be printed out or displayed on other monitors through the Internet, and color matching between the original and the reproduction is very important. The color management systems (CMSs) are useful for the color matching. CMSs utilize device profiles, in which color characteristic information is stored, and these profiles are generated by device characterization. Thus, an accurate characterization of the monitor is essential for better color matching. CRT monitor characteristics can be described by the tone reproduction curves (TRCs) of each channel, and color additive matrix. In this paper, these characteristics were investigated from a physical point of view. Various kinds of flare and the interdependence among the channels were also investigated and verified. The definition of the term “gamma” is clarified, which is very often used to describe the TRC. Various definitions are compared and a new definition of S-γ is proposed. 相似文献
62.
Naoya Inazumi Yoshimi Sueishi 《Journal of inclusion phenomena and macrocyclic chemistry》2010,68(1-2):93-98
The equilibrium constants for the inclusion complexation of octaethyl-p-tert-butylcalix[8]arene octaacetate (Calix-B8-EA) with methylene blue (MB) were determined spectrophotometrically. Calix-B8-EA, which has a flexible hydrophilic pseudo-cavity formed by polyfunctional esters on the lower rim, is an effective receptor for alkali and alkaline-earth cations, and its ester carbonyl group forms the complex with metal cations. We have examined the ability to include the organic molecule (methylene blue (MB)) into the upper main cavity of Calix-B8-EA formed the complex of alkali metal cations with ester carbonyl groups on the lower rim. It was found that Calix-B8-EA forms a 1:1 inclusion complex of MB with the upper main cavity and, in the presence of excess alkali metal cations, the association constants increase with an increase in the size of the metal cations complexed with the polyfunctional groups on the lower rim. Further, the structure of the inclusion complex of MB with cation-complexed Calix-B8-EA is characterized by 2D ROESY-NMR measurements. Based on the results, we have demonstrated the control of the inclusion ability by changing the portal size of the calixarene cavity. 相似文献
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We propose and experimentally demonstrate a 40 Gb/s secure optical communication system with on-off-keying (OOK) modulation format by using a time domain spectral phase en/decoding scheme, which employs a highly dispersive element and high-speed phase modulator for introducing significant symbol overlapping for both the encoded and incorrectly decoded noiselike signals to enhance the information security against eavesdropping using a power detector. The influence of dispersion and chip modulation rate on the symbol overlapping of the incorrectly decoded signal has been analytically investigated and experimentally verified. Security enhancement for 40 Gb/s OOK data using fast reconfigurable 40 Gchip/s optical codes with code lengths of up to 1024 has been demonstrated and compared with a 10 Gb/s system. 相似文献
66.
Magnetite particles were synthesized through a process including dissolution of Fe(OH)2 and precipitation of an oxidized phase in aqueous solution. The Fe3+ ion was added at the beginning of the synthesis to accelerate the formation of magnetite, control the particle size and improve the monodispersibility. It was found that the addition of Fe3+ ion affected the nucleation and the formation of magnetite particles significantly. Magnetite nanoparticles with small particle size and narrow size distribution were obtained. Furthermore, high magnetic properties were obtained in small particle size. The particle size and magnetic properties increased through the increase of Fe2+/Fe3+ ratio. 相似文献
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Masashi Shiotsuki Atsushi Nakagawa Jesus Rodriguez Castañon Naoya Onishi Tatsurou Kobayashi Fumio Sanda Toshio Masuda 《Journal of polymer science. Part A, Polymer chemistry》2010,48(23):5549-5556
End‐functionalized poly(phenylacetylene)s were synthesized by the polymerization of phenylacetylene (PA) using the well‐defined palladium catalysts represented as [(dppf)PdBr(R)] {dppf = 1,1′‐bis(diphenylphosphino)ferrocene}. The Pd catalysts having a series of R groups such as o‐tolyl, mesityl, C(Ph)?CPh2, C6H4‐o‐CH2OH, C6H4‐p‐CN, and C6H4‐p‐NO2 in conjunction with silver triflate polymerized PA to give end‐functionalized poly(PA)s bearing the corresponding R groups in high yields. The results of IR and NMR spectroscopies and MALDI‐TOF mass analyses proved the introduction of these R groups at one end of each polymer chain. The poly(PA) bearing a hydroxy end group was applied as a macroinitiator to the synthesis of a block copolymer composed of poly(PA) and poly(β‐propiolactone) moieties. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献
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G. Battistoni C. Bloise P. Campana A. Ciocio E. Iarocci V. Chiarella G. P. Murtas G. Nicoletti L. Satta G. Bologna C. Castagnoli A. Castellina B. D'Ettorre Piazzoli P. Galeotti G. Mannocchi P. Picchi O. Saavedra S. Vernetto E. Bellotti E. Fiorini C. Liguori P. Negri A. Pullia S. Ragazzi M. Rollier L. Zanotti D. C. Cundy M. Price 《Il Nuovo Cimento C》1986,9(2):551-558
Summary A trigger dedicated to the search of superheavy monopoles operates since about two years in the NUSEX apparatus, installed
in the Mont Blanc tunnel. Monopoles are identified by time of flight and visualization of the pulses involved in a trigger.
The present upper limit on monopole flux is 2.3·10−13 cm−2 s−1 sr−1 (90% c.l.).
Riassunto Da circa due anni è operativo sull'apparato NUSEX, installato nel tunnel del Monte Bianco, un trigger dedicato alla ricerca dei monopoli previsti dalle teorie di grande unificazione. L'identificazione dei monopoli è basata sul tempo di volo e sulla localizzazione nello spazio degli impulsi coinvolti nel trigger. Il limite superiore fino ad oggi raggiunto per il flusso di monopoli è 2.3·10−13 cm−2s−1 sr−1 (90% c.l.).
Резюме Триггерная схема, предназначенная для поиска сверхтяжелых монополей, действует в течение почти двух лет в установке NUSEX, расположенной в туннеле под Мон Бланом. Идентификация монополей основана на времени пролета, а локализация в пространстве осуществляется с помощью импульсов в триггерной схеме. Настоящий верхний предел на поток монополей составляет 2.3· ·10−13 см−2 с−1 ср−1 (к 90% вероятностью).相似文献