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Volume 58 (1995)
- Issue 6 Pages 518-
- Issue 5 Pages 428-
- Issue 4 Pages 316-
- Issue 3 Pages 209-
- Issue 2 Pages 80-
- Issue 1 Pages 2-
Volume 58, Issue 4
Displaying 1-10 of 10 articles from this issue
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Atsushi MIZUNO, Naomichi OKAMOTO, Ryoka MATSUSHIMA1995 Volume 58 Issue 4 Pages 316-320
Published: August 25, 1995
Released on J-STAGE: August 11, 2011
JOURNAL FREE ACCESSThe second-harmonic (SH) activities of N-substituted 2-methyl-4-nitroanilines (MNA) were measured with Nd: YAG laser (1064nm) by the powder method. Single crystals of the MNA derivatives showed SH-activities of 30-200×urea, while those of pNA were almost SH inactive. Mixed crystals of these derivatives with the parent MNA showed SH-activities of 100-200×urea without substantial loss of activity at room temperature. On the contrary, mixed crystals of p-nitroaniline (pNA) with its derivatives showed very high SH-activities, which were rapidly lost on standing at room temperature. These results imply that the methyl substituent at the 2-position plays a crucial role in crystal packing and stability. It appears that the atmospheric moisture does affect the structure and property of the crystals at room temperature.View full abstractDownload PDF (636K) -
Ryoka MATSUSHIMA, Hirotaka MIZUNO, Hideki ITOH1995 Volume 58 Issue 4 Pages 321-328
Published: August 25, 1995
Released on J-STAGE: August 11, 2011
JOURNAL FREE ACCESS2-Hydroxychalcones with 4'-amino substituents underwent facile photochemical conversion into highly colored flavylium ions on UV irradiation in aqueous ethanol solution in the pH region of 4-6. The colored solutions were stable upon prolonged irradiation with visible light. Some derivatives featured good reversibilities of repeating photo-coloration and thermal reversion at 50°C without significant fatigue, while some other derivatives exhibited high thermal stabilities in the colored forms. Similar photochemical coloration occurred in solid polymers, but irreversible thermal bleaching took place. Structurereactivity relationships and mechanisms were discussed in terms of the frontier orbital theory.View full abstractDownload PDF (887K) -
Yoshiro YONEZAWA, Hideaki ISHIZAWA, Tomoo SATO, Toshihito MIYAMA1995 Volume 58 Issue 4 Pages 329-339
Published: August 25, 1995
Released on J-STAGE: August 11, 2011
JOURNAL FREE ACCESSThe structure of the mixed J-aggregates consisting of two kinds of cyanine dyes is classified into four types, separate aggregate (S-type), mosaic aggregate (M-type), persistence-type aggregate (HP-type), amalgamation-type aggregate (HA-type), each of which is characterized by the intrinsic spectroscopic properties. We have taken up several cyanine dyes capable of forming the J-aggregate in the monolayer assemblies (LB films), quinocyanine dyes (dye I, S120), thiacarbocyanine dyes (dye II, dye III), oxacyanine (S9), thiacyanine (S11), and tried to fabricate the mixed J-aggregate in the LB films incorporating two kinds of cyanine dyes, dye I: dye II, dye II: dye III, S9: S11, S120: dye I. Two J-bands and two peaks of resonance fluorescence inherent to the dye I aggregate and the dye II aggregate, as well as the Perrin-type kinetics of quenching and sensitization of resonance fluorescence in the dye I: dye II LB films indicate that the dye I-dye II combination forms the S-type aggregate. Although two J-bands are observed, some blue shift of the J-band and the similar molecular structures of the S9-S11 combination and the S120-dye I combination may suggest that those dyes form the M-type aggregates in the LB films. A single J-band and a single peak of resonance fluorescence are evident in the dye II: dye III LB films, whose peak positions gradually shift according as the molar mixing ratio of two dyes. It is suggested that the dye II-dye III combination could form the HA-type aggregate in the LB films. These features are interpreted in terms of “steric requirement” representing the structure similarity and “electronic requirement” expressed by a parameter θDA.View full abstractDownload PDF (1408K) -
Mitsuo KAWASAKI, Hironori ISHII1995 Volume 58 Issue 4 Pages 340-351
Published: August 25, 1995
Released on J-STAGE: August 11, 2011
JOURNAL FREE ACCESSReported in this article is a comparative STM imaging of self-assembled, two-dimensional J-aggregate of 1, 1'-diethyl-2, 2'-cyanine and H-aggregate of 1, 1'-diethyl-2, 2'-carbocyanine, adsorbed on a highly planar Ag (111) film covered with a pseudo-silver-halide monolayer. A superior uniformity in the dye coverage also allows the spectral properties of the monolayer dye aggregates, as measured by conventional spectroscopy methods, to be reasonably correlated with the local structural information extracted by STM imaging. The image of the H-aggregate is characterized by a parallel-column structure, wherein each column is consisted of planar dye molecules stacked one-dimensionally at a relatively large slip angle. In contrast, the image of the J-aggregate suggests that a real two-dimensional network of dye molecules is established with a considerably small slip angle of-20°. The suggested molecular arrangements indicate that both dye cations and counter anions may be coadsorbed in a single monolayer structure. A dye imaging mechanism involving the delocalized π-electrons of dye cations is also discussed.View full abstractDownload PDF (13531K) -
Kazuo OTA, Teiji HABU, Takumi OKAYAMA1995 Volume 58 Issue 4 Pages 352-360
Published: August 25, 1995
Released on J-STAGE: August 11, 2011
JOURNAL FREE ACCESSWe selected two cyanine dyes (NK 76, NK 467) which show hypsochromic shift of absorption maxima due to self-association of two dye molecules in solution, and planned to regulate dye association in LB film.
The inclusion complex of dye and Trimethyl-fi-cyclodextrin (TM-β-CD) was synthesized. It was found that NK 76 was included at the end of CD's cylindrical structure, whereas NK 467 in the cavity by analyzing circular dichroism spectra for mixture of dye and TM-β-CD in chloroform solution.
Hexakis (6-dodecylamino-deoxy)-β-CD (HDD-fi-CD) was synthesized. LB films were prepared using dye and HDD-β-CD changing the mixing ratio, dye: HDD-β-CD. Visible absorption spectra showed that at the mixing ratio, NK 76: HDD-β-CD =1: 6, and NK 467: HDD-β-CD =1: 7, association of dye molecular disappeared.View full abstractDownload PDF (1025K) -
Masashi IWASAKI, Kadzuyuki HIGASHINAKA, Toshio TANAKA1995 Volume 58 Issue 4 Pages 361-367
Published: August 25, 1995
Released on J-STAGE: August 11, 2011
JOURNAL FREE ACCESSInfluence of substituents, introduced to 5 (4)-and 6-positions of an anionic thiacyanine dye, on molecular association was studied spectroscopically. The larger the substituents were, the larger was the tendency of dye molecules to bimolecular association (dimerization), suggesting that van der Waals' force mainly drove dimerization. The tendency to J-aggregation was affected not only by van der Waals' force but also by electrostatic interactions between intramolecular local charges and by geometrical factors.View full abstractDownload PDF (885K) -
Norihiro MATOBA, Masayuki SAITO, Masaru OHNISHI1995 Volume 58 Issue 4 Pages 369-372
Published: August 25, 1995
Released on J-STAGE: August 11, 2011
JOURNAL FREE ACCESSWe have proposed Fixed Block Truncation Coding (FBTC) for Hard Copy. FBTC algorithm is fixed length coding and has four major characteristics.(1) It approves superior appearances in natural images, CG images and text images.(2) Image editing is available under compressed state.(3) Small size hardware.(4) High speed processing.
On the basis of FBTC algorithm mentioned above, we confirmed that semiconductor image memory could be replaced with secondary storage such as hard disk drive and drastic smaller memory.View full abstractDownload PDF (505K) -
Mikio TAKEMAE1995 Volume 58 Issue 4 Pages 373-375
Published: August 25, 1995
Released on J-STAGE: August 11, 2011
JOURNAL FREE ACCESSWith the advent of the multimedia era, the needs for digial still cameras are growing rapidly. Based on these backgrounds, We have developed SLR-type digital still cameras mainly aimed for business market. In this market, the digital still cameras are sometimes used together with the conventional silver-halide SLR cameras. So the compatibility of lenzes, acsessories and operation is very important. Many cameraback-type SLR digital still cameras in the market, however, have many problems, such as the difficulty of viewing the finder, inappropriate area for focusing and light metering, the shift of apparent focul distance of lenzes. To eliminate these problems, we developed the image reduction optics. Because of this optics, we could reject these problems, furthermore, could get the TTL flash function on the digital still camera.View full abstractDownload PDF (350K) -
Shin OHNO1995 Volume 58 Issue 4 Pages 376-385
Published: August 25, 1995
Released on J-STAGE: August 11, 2011
JOURNAL FREE ACCESSIn the beginning of the 1980s, the first electronic still photography system was proposed by Japanese manufacturer with the line up of prototype products. During the past decade, technologies for the new electronic imaging has been proceeded in three steps of the still video, the electronic photography and the digital photography systems. The first still video (SV) system had based on the analog signal processing followed to TV systems. The second electronic photography (EP) system was the digitized version of SV and independent from TV systems. The current digital photography (DP) is a merged system of the electronic photography and the conventional silver halide chemical photography. This paper deals with the advance of electronic still imaging systems and their future trend.View full abstractDownload PDF (10370K) -
Kenji TOYODA1995 Volume 58 Issue 4 Pages 386-388
Published: August 25, 1995
Released on J-STAGE: August 11, 2011
JOURNAL FREE ACCESSAs an example of consumer use of digital photography, the data libraries of the “Photoforum” in a major communication network service are studied in terms of file size, number of downloads and so on.View full abstractDownload PDF (2199K)
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