• Journal of the Korean Ceramic Society
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• v.28 no.3
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• pp.252-258
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• 1991

Spectral properties of europium activated intermediate compounds in the system R2O3-P2O5(R=La, Y, and Gd) are presented, including also phosphors with bismuth and vanadate sensitization. The sensitized phosphors are less efficient than unsensitized phosphors. (The ratio of oxygen to phosphorus effects the charge transfer band) Most phosphors have low efficiencies, but La3PO7 and Gd3PO7 hosts are possible for commercial luminescent materials.

• Journal of the Korean Applied Science and Technology
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• v.13 no.1
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• pp.31-39
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• 1996

In this study, sensitizing dye was prepared by the reaction of 2-methyl-3-sulfopropyl-4, 5-naphthothiazolium(inner salt) with triethyl orthoformate in the presence of triethylamine. The product was identified by using various analytical tools such as Elemental analyzer, IR spectrophotometer, UV-Vis spectrophotometer, $^1H-NMR$ spectrometer, TGA and DSC. Therefore, it was concluded that naphthothiazolo carbocyanine dye can be used as red-sensitizing dye for the spectral sensitization of photographic emulsion.

• Journal of the Korean Applied Science and Technology
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• v.16 no.3
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• pp.199-203
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• 1999

The symmetric benzoxazolo carbocyanine is of industrial importance as green-sensitizing dye in the spectral sensitization of emulsion microcrystals in positive paper and negative film-making. The stability on the solvents of benzoxazolo carbocyanine dye was measured by UV-Vis spectrophotometer, and then all of solvents were stabilized sensitizer. The maximum absorption peak range in methanol, acetonitrile, acetone, DMF, dichloromethane, chloroform solvents was $501nm{\sim}511nm$. But it was identified that only methanol can be used to photographic emulsion. The photographic characteristics have contrast of 2.8, speed of 50-55$(lux{\cdot}sec)^{-1}$, fog of 0.07-0.08, respectively.

• Journal of the Korean Chemical Society
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• v.19 no.4
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• pp.269-279
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• 1975

Photosensitive properties of naphthoquinone-1,2-diazide-5-sulfonyl esters (PGND, BEND and PVAND) of polyglyceryl phthalate(PG), bisphenol A-epichlorohydrin condensate(BE) and polyvinyl alcohol(PVA) were investigated by the change of solubility before and after exposing to light. Various samples coated on glass or quartz plates were exposed to light under various conditions and steeped in aqueous alkali solution, and then the yield of residual film(W/W0) was determined. The yield of residual film, which was closely related to the sensitivity of the film, was affected by the degree of polymerization of the backbone resin, sensitizers and their concentration. In polymer homologs, the sensitivity was dependent on the degree of polymerization(the higher, the better). And also, it was most effective when 5 % of sensitizers to esters was used. The minimum exposed time was 0.6 min. for PGND-1, 1.0 min. for BEND-1, and 3.0 min. for PVAND-1. Most effective sensitizers for PGND, BEND and PVAND among those used here were benzanthrone, 5-nitroacenaphthene and picramide, respectively. The spectral sensitivities of PGND, BEND and PVAND were examined by comparing their spectrograms with UV-spectra in a solid state. Also, the sensitization and spectral sensitivity of the above polymers were studied. All the polymers containing the sensitizers showed optical sensitization. From the fact that in either case of sensitized or unsensitized sample, the ranges of absorption-maximum wave length were almost consistent with sensitivity maximum wave length, it was proved that the light absorbed by a sample served efficiently for photochemical reactions. Benzanthrone was found to be an excellent sensitizer for PGND.

• The Journal of Information Technology
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• v.7 no.2
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• pp.1-5
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• 2004

The symmetric 9-phenyl-5,5'-diphenyl-3,3'-bis-(3-sulfopropyl)-benzoxazolo carbocyanine triethyl ammonium salt is of industrial importance as green-sensitizing dye in the spectral sensitization of emulsion microcrystals in negative film and positive paper-making. The stability on the solvents of benzoxazolo carbocyanine dye was measured by UV-Vis spectrophotometer, and then dye was stabilized in various solvents. The maximum absorption peak range in various solvents was 507nm~515nm. It was identified that the solvents can be used to photographic emulsion.

• Journal of the Korean Applied Science and Technology
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• v.13 no.3
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• pp.73-81
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• 1996

In this study, sensitizing dye was prepared by the reaction of 2-methyl-3-sulfopropyl-4,5-naphthothiazolium(inner salt) with triethyl orthobenzoate in the presence of triethylamine. The product was identified by using various analytical tools such as elemental analyzer, IR spectrophotometer, UV-Vis spectrophotometer, $^1H-NMR$ spectrometer, TGA and DSC. Therefore, it was concluded that 9-phenyl-3,3'-bis(3-sulfopropyl)-4,5,4',5'-naphthothiazolo carbocyanine triethyl ammonium salt can be used as red-sensitizing dye for the spectral sensitization of photographic emulsion.

• Journal of the Korean Applied Science and Technology
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• v.12 no.2
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• pp.5-11
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• 1995

In the study, sensitizing dye was prepared by the reaction of 2-methyl-3-sulfopropyl-5-phenyl-benzoxazolium(inner salt) with ortho-ester in the presence of triethylamine. The product was identified by using various analytical tools such as Elemental analyzer, IR spectrophotometer, UV-Vis spectrophotometer, $^{1}H$-NMR spectrometer, TGA and DSC. Therefore, it was concluded that benzoxazolo carbocyanine dye can be used as green-sensitizing dye for the spectral sensitization of photographic emulsion.

• Journal of the Korean Chemical Society
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• v.37 no.2
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• pp.213-219
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• 1993

The electrochemical spectral sensitization of $SnO_2$ electrodes with rhodamine B was studied. Photocurrent was measured in the presence of a variety of supersensitizers including ascorbic acid and KI. In the presence of ascorbic acid, the increase in the concentration of ascorbic acid, pH of the solution, or the potential applied to $SnO_2$ up to 0.6 V vs. SCE enhanced the photocurrent. However, ascorbic acid produced considerably high dark current due to its low reduction potential. On the other hand, KI produced low but stable photocurrent. The results, together with the solvent effect on the photocurrent, were taken into account to elucidate the mechanism of photosensitization in the presence of ascorbic acid or KI.

• Journal of the Korean Chemical Society
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• v.36 no.1
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• pp.75-80
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• 1992

The electrochemical spectral sensitization of a $SnO_2$ electrode with eosin B, a Xanthene dye, has been studied in acetonitrile. Measurements of the photocurrent have been carried out in the presence of supersensitizers such as thiourea, 1-allyl-2-thiourea, NaSCN, and NaI. The magnitude of the supersensitized photocurrent was greater than that of the sensitized photocurrent for all of the supersensitizers studied. However, the long time span of irradiation causes a significant decrease of the supersensitized photocurrent as well as the absorbance. These results, together with infrared spectra and fluorescence spectra, are taken into account to elucidate the mechanism of photoreaction between eosin B and supersensitizers in acetonitrile.

• Bulletin of the Korean Chemical Society
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• v.30 no.7
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• pp.1553-1558
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• 2009

A series of Eu(III) complexes with various neutral ligands (2,2’:6’,2"-terpyridine (T), diglyme (D), 1N-(2-dimethylamino) ethyl)-1N, 2N, 2N-trimethylethane-1,2-diamine (PT), di-(2-picolyl)-amine derivative (HT), and multidentate terpyridine derivative (DT)) were synthesized to investigate the effect of coordination environment on the sensitized luminescence of Eu(III) complexes. The nine coordination sites of the $Eu^{3+}$ ion are occupied by three bidentate carboxylate moieties and one neutral ligand. The highest emission intensity is obtained for $Eu^{3+}$- $[NA]_3$ (PT), due to the difference in energy transfer efficiency and symmetry of the first coordination sphere of $Eu^{3+}$ ion. But, the lowest emission intensity is obtained for $Eu^{3+}$-$[NA]_3$(T). Terpyridine may not play an important role antenna for photosensitizing $Eu^{3+}$ ion. It could be attributed to the weak spectral overlap integral J value between its phosphorescence band and $Eu^{3+}$ion absorption band. Therefore, different coordination environment of $Ln^{3+}$ ion play an important role in providing sensitization of lanthanide ion emission.