• Textile Coloration and Finishing
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• v.13 no.5
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• pp.24-24
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• 2001

Kinetics and mechanism for alkaline hydrolysis of C. I. Disperse Blue 79(B-79) which is 4-N, N-diacetoxyethyl-2-acylamino-5-ethoxy -2′-bromo-4′,6′-dinitroazobenzene were investigated. The color strength of B-79 in acetone/water solutions of various NaOH concentrations decreased continuously. The hydrolysis rate of B-79 increased with increasing alkali concentration and appeared following first order reaction. The observed rate constants for various concentrations of B-79 showed similar values, and B-79 was hydrolyzed by first order reaction for dye concentration. Therefore, it was confirmed that the overall reaction follow second order kinetics and proceed via S/sub n/2 reaction. From the study on kinetics and spectrometric analysis, it was proposed that the rate determining step of the hydrolysis reaction of B-79 is the nucleophilic substitution reaction - that is the reaction of the rapid attack of $OH^{-}$ on the carbon atom, which is in acceptor ring, adjacent to azo group to break the C-N bond. And it was also found that the final hydrolysis products of B-79 include both the acceptor ring in the form of sodium salt and the donor ring possessing 4-N,N-dihydroxyethyl group converted from 4-N,N-diacetoxyethyl group.

• Textile Coloration and Finishing
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• v.13 no.5
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• pp.312-319
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• 2001

Kinetics and mechanism for alkaline hydrolysis of C. I. Disperse Blue 79(B-79) which is 4-N, N- diacetoxyethyl -2- acylamino-5-ethos y -2'-bromo-4',6'-dinitroazobenzene were investigated. The color strength of B-79 in acetone/water solutions of various NaOH concentrations decreased continuously. The hydrolysis rate of B-79 increased with increasing alkali concentration and appeared following first order reaction. The observed rate constants for various concentrations of B-79 showed similar values, and B-79 was hydrolyzed by first order reaction for dye concentration. Therefore, it was confirmed that the overall reaction follow second order kinetics and proceed via $S_N2$ reaction. From the study on kinetics and spectrometric analysis, it was proposed that the rate determining step of the hydrolysis reaction of B-79 is the nucleophilic substitution reaction - that is the reaction of the rapid attack of OH- on the carbon atom, which is in acceptor ring, adjacent to auto group to break the C-N bond. And it was also found that the final hydrolysis products of B-79 include both the acceptor ring in the form of sodium salt and the donor ring possessing 4-N,N-dihydroxyethyl group converted from 4-N, N-diacetoxyethyl group.

• Journal of Sericultural and Entomological Science
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• v.26 no.2
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• pp.1-6
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• 1984

The present study was made to establish the purification method of mature microsporidian spores by iso-density equilibrium technique using percoll and the serological discrimination by an indirect fluorescent antibody technique. The purification of new microsporidian spores took effect in the three steps purification method(precentrifugation-percoll iso-density equilibrium centrifugation-rising). There were clear differences in the size of spores between the new microsporidia and N. bombycis. The spores of N. bombycis is short elliptical of 2.07 in a ratio of length to width in diameter while that of new microsporidia is characterized with long elliptical shape which shows a ratio of 2.76 in length to width in diameter. The specific antigens of new microsporidia K79 spores was showed in the spores wall by the indirect fluorescent antibody reaction, and it was affected by the antibody against N. bombycis which antiserum was diluted in 1:20. It means that the new microsporidia K79 is serologically not identical to N. bombycis.

• Proceedings of the Materials Research Society of Korea Conference
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• 2002.11a
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• pp.79-79
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• 2002

• Journal of Sericultural and Entomological Science
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• v.27 no.1
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• pp.1-11
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• 1985

In order to clarify the taxanomic position of a new microsporidia K79 which was isolated from the silkworm larvae, Bombyx mori L. in Korea in 1979, the following several experiments such as estimation of pathogenicity in different instar, histopathological examination under light and electronic microscope and examination of fine structure of the sporse were carried out and their result obtained are as follows. In the test of pathogenicity by oral inoculation, the new microsporidia K79 was lower than Nosema bombycis and the susceptibility of the new microsporidia to silkworm was getting lower as the silkworm larvae grew. The lesion of Silkworms' tissue which was infected with the new microsporidia K79 was found in the epithelial cells of trachea, fat body and silk gland cells. The developmental process of the new microsporidia K79 in vivo could be divided into the following five stages: sporoplasm, schizont, sporont, sporoblast, and spore. The process was just the same as the of N. bombycis, but its development was slower than that of N. bombycis. Several differences in the fine structure of the spore under electron microscope, which could be important keys for the classification of microsporidia, were obtained. Anchoring disk and polaroplast lamella of the new microsporidian spore were disclosed to be different from those of N. bombycis. An average number of polar filament coils of the new microporidian spore was 16 at an angle of 75$^{\circ}$. On the basis of various keys for the classification of microsporidia, the results obtained from various experiments proved that the newly isolated microsporidia should be classified into the Genus, "Nosema", nut is further classification for species should be conducted in the future. Therefore, it may be reasonable that the new microsporidia is temperally classified as Nosema sp. K79 considering the fact that it was discovered in Korea in 1979.a in 1979.

• The Korean Journal of Ecology
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• v.28 no.5
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• pp.295-303
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• 2005

The sexual dimorphism and intra sexual dimorphism in males of Rhinogobius brunneus were investigated at Jiam stream, a tributary of the Bukhan river from May, 2005. The frequency distributions in standard length were similar for the females and maleLs, but maleSs were smaller than the females and maleLs. The ratio of MaleL (N=79) to males (N=79) was 1 : 0.46. The comparison between female (N=79) and maleL (N=79) gave significant differences (P<0.05) in 18 morphometric characteristics (SNL, AHD, PHD, ML, DL, MW, AHW, IFW, PHW, ED, HL, FDFL, SDFB, CFL, AFB, VFL, PFL, PFB) and 12 characteristics (SNL, AHD, ML, DL, MW, AHW, IFW, PHW, HL, FDFI, CFL, PFB) (P<0.001). Eight morphometric characteristics (SNL, ML, DL, MW, HL, CFL, VFL, PFL) in female (N=36) and males (N=36) had significant differences (P<0.05) and three characteristics (ML, DL, HL) had very significant differences (P<0.001). Eleven characteristics (SNL, AHD, PHD, ML, DL, MW, AHW, IFW, PHW, HL, FDFL) were significantly different in maleL (N=36) and males (N=36) (P<0.05) and six (ML, DL, MW, AHW, HL, FDFL) were very significantly different (P<0.001).

• KIEE International Transactions on Electrophysics and Applications
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• v.5C no.2
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• pp.54-57
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• 2005

Photoreflectance (PR) has been measured to investigate the characterization of the Si$_{3}$N$_{4}$Al$_{0.21}$ Ga$_{0.79}$As/GaAs and Al$_{0.21}$Ga$_{0.79}$As/GaAs heterostructures. In the PR spectrum, the caplayer thickness was 170 nm and Si$_{3}$N$_{4}$ was utilized as the capping material. The C peak is confirmed as the carbon defect with residual impurity originating from the growth process. After annealing, in the presence of the Si$_{2}$N$_{4}$ cap layer, band gap energy was low shifted. This result indicates that the Si$_{3}$N$_{4}$ cap layer controlled evaporation of the As atom.

• Proceedings of the Materials Research Society of Korea Conference
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• 1999.11a
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• pp.79-79
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• 1999

• Proceedings of the KTCVS Conference
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• 1995.10a
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• pp.79-79
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• 1995

• Proceedings of the Korea Society of Costume Conference
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• 2002.10a
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• pp.79-79
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• 2002