• Textile Coloration and Finishing
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• v.27 no.2
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• pp.155-163
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• 2015

In dyeing cotton fabric with the Indigo Pulverata Levis, this research examined the effect of the sodium dithionite($Na_2S_2O_4$). For the separation of the Indigo-calcium hydroxide complex in the alkaline solution of the Indigo Pulverata Levis, the reduction with the $Na_2S_2O_4$ at $25^{\circ}C$ was more effective than the solution boiling. The concentration of Indigo in the cotton fabric increased with the increase of Indigo Pulverata Levis, but the concentration of indirubin did not increase particularly. The optimum temperature for the reduction was $60^{\circ}C$, and K/S value of dyed fabric decreased at over $60^{\circ}C$. The concentration of indigo and indirubin in the cotton fabric decreased as $Na_2S_2O_4$ concentration increased. In treating cotton fabric dyed with the Indigo Pulverata Levis by the $Na_2S_2O_4$, the concentration of indirubin decreased and the surface color of dyed cotton changed from purple blue to blue while the treatment temperature was getting higher.

• Bulletin of the Korean Chemical Society
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• v.14 no.4
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• pp.461-465
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• 1993

Reductive transformations of gem-bromonitro compounds and ${\alpha}$-nitro ketones were carried out conveniently with sodium dithionite by using dioctyl viologen as an electron-transfer catalyst in dichloromethane-water two-phase system:the bromine atom in gem-bromonitro compounds and the nitro group in ${\alpha}$-nitro ketones are replaced by hydrogen.

• Bulletin of the Korean Chemical Society
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• v.18 no.11
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• pp.1145-1146
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• 1997

• Textile Coloration and Finishing
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• v.20 no.3
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• pp.18-24
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• 2008

The purpose of this study is to develop the dyeing method with dry leaves of indigo plant. Coloring matter was extracted from dry leaves of indigo plant with hot sodium hydroxide solution. The extract was reduced with sodium dithionite, and it was used for dyeing cotton fabrics under various conditions. UV-visible absorption spectra of extract, reduction rate of extracts by reducing agent, and the surface color of dyed cotton, lightfastness were examined. For the initial 20 minutes, the absorbance of indigo solution rapidly decreased. However, several hours later, the decreasing rate retarded. By repeating the dyeing process, the shade looked deeper and deeper. At $30-40^{\circ}C$, the value of K/S reached the highest point. The concentration of indigo solution in dye bath seemed to playa critical role for the reaction of the reducing agent. It was observed that the surface color of cotton fabrics was getting bluish and its degree of value and chroma seemed slightly decreased as the K/S value was increasing. The lightfastness was clearly enhanced by increasing the K/S value.

• 보존과학연구
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• s.16
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• pp.41-58
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• 1995

Several comparisons of treatment methods for stabilizing corroded Chinese coins at Shin-an marine sites were investigated. In aqueous solution, the seexamination were performed to show whether chloride ions are gradually removed, patination changes are acceptable and archaeological details are identified. The six desalting methods showed that the orders of removal of chloride ions were ranked electrolysis (electolyte : 0.1M sodium sesqui.)> 5% sodium dithionite(1M NaOH)> 5%sodium dithionite(0.1M sesqui.)> 5% citric acid> 0.1M sodium sesquicarbonate>deionized water. As the examinations of moisture absorption to the relative humidity has compared for bronze disease, all of desalted coins for the R.H 53% and R.H 75%except to R.H 95% are showed serious bronze disease.

• Journal of the Korean Chemical Society
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• v.47 no.4
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• pp.339-344
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• 2003

Paraquat is an effective and widely used herbicide, but it is also very toxic to humans. It is well-known that urine paraquat concentration is one of the most important prognostic indicator for paraquat-poisoning. Quantitative analysis of paraquat, however, are not generally used in clinical laboratories. In this work, a new test strip to detect paraquat concentration using sodium dithionite in urine was developed. Using these second-derivative method, the test strip prepared in $0.5{\%}$ borate buffer (pH 8.0), 0.25 M $Na_2S_2O_4,\0.1~0.8{\%}$ PVP, and $1{\%}$ decanol showed not only better color reaction but also an excellent application possibility to be used in automatic analyzer.

• YAKHAK HOEJI
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• v.32 no.5
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• pp.295-303
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• 1988

For microbial production of acetaminophen, a popular analgesic-antipyretic from aniline, we screened various fungi and bacteria. And we succeeded to some extents in acetaminophen production by successful protoplast fusion between S. lividans and S. globisporus and also between S. rimosus and S. aureofaciens. However, more fertile results might be brought via performing the cloning of acetanilide p-hydroxylation genes of Streptomyces in yeast. This study was initiated to determine whether the acetanilide p-hydroxylase of Streptomyces is cytochrome P-450 species or non-heme iron protein species. The p-hydroxylationactivity on acetanilide in S. aureofaciens ATCC 10762 was found to be unstable on exposing to the air. However, 100,000xg supernatant of the cell free extracts which were prepared in $N_2$ atmosphere showed the p-hydroxylation activity. Characteristic absorption peak of cytochrome P-450 after reduction with dithionite and addition of CO was not observed in the region of 450nm. Moreover, metyrapone and 2, 6-dichloroindophenol did not affect this enzyme activity, but sodium azide, sodium cyanide, cupric sulfate, cadmium chloride, ${\alpha}$, ${\alpha}'-dipyridyl$, and o-phenanthroline reduced p-hydroxylase activity considerably. S. fradiae NRRL 2702 was shown to have strong p-hydroxylation activity in intact cells. This activity disappeared in its cell free extracts. In its 100,000xg supernatant, however, characteristic absorption peak of cytochrome P-450 after reduction with dithionite and addition of CO was observed at 446nm. Thus, the results herein presented suggest that acetanilide p-hydroxylase of Streptomyces aureofaciens is not related to cytochrome P-450 and may include non-heme iron protein for its activity. However, it is not clear whether acetanilide p-hydroxylase in S. fradiae belongs to the same category of S. aureofaciens.

• Textile Coloration and Finishing
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• v.32 no.4
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• pp.193-198
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• 2020

In this study, the validity of extracts from food waste as biocatalyst for indigo reduction was examined. Dried food wastes such as apple peel and corn waste were water-extracted and freeze-dried. The reducing power of extracts for indigo was evaluated by the oxidation-reduction potential(ORP) measurement of reduction bath and color strength(K/S value) of the fabrics dyed in the indigo reduction bath. Total sugar contents of the apple peel and corn waste extracts were 60.56% and 62.36%, respectively. Antioxidant activity was 64.78% for the extract of apple peel and 7.96% for the extract of corn waste. Indigo reduction took place quickly with both extracts, and maximum color strength was obtained up to 15.91 and 12.11 within 1-3 days, respectively. The oxidation-reduction potential of reduction bath was stabilized in the range of -500 ~ -620 mV according to the kinds of food waste and the extract concentration. At higher concentration of the extracts, reduction power was maintained for longer time and stronger color strength was obtained. Compared to sodium dithionite, the reducing power of the studied extracts was lower, but the reduction stability was superior to it. The studied extracts were effective biocatalyst as biodegradable and safe alternatives to sodium dithionite for indigo reduction.

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.2
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• pp.147-154
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• 1984

Two Fe-hydrous oxide A,B and one Al-hydroxide minerals were synthesized precipitating Fe $Cl_3$ and $AlCl_3$ with alkali solution(NaOH) at pH 6.0, 12.0 and 4.5 respectively, for precise understanding of physico-chemical and surface charge characteristics of soils in which these minerals are dominant. Identification of these final products, effect of free and amorphous materials on X-ray diffraction analysis, particle size distribution and surface change characterics of these minerals were performed. Fe-hydroxide A and B were identified as great deal of X-ray amorphous material and as goethite with large amount of X-ray amorphous material, respectively. Dehydration by oven at $105^{\circ}C$ of these minerals exhibited akaganeite peaks with low X-ray amorphous hump and pure goethite peaks for Fe-hydroxide A and B, respectively. Both minerals, however, turned into hematite upon firing at $550^{\circ}C$. On the other hand, Al-hydroxide identified as mixture of gibbsite and bayerite of around 7:3 ratio. Application of sodium dithionite and ammonium oxalate solutions for removal of free or amorphous Fe and Al from these minerals revealed that only peak intensities of Al-hydroxide system were enhanced upon Al-extraction by oxalate solution even though dithionite solution was much powerful to extract Fe from Fe-hydrous oxide systems. Original(wet) Fe-hydrous oxide A has the highest specific surface and surface charge development(negative and positive), and the greatest amount of less than $2{\mu}m$ sized particles. Specific surface and clay sized particles(less than $2{\mu}m$) of Fe-hydrous oxide A, however, were drastically reduced upon dehydration($P_2O_5$ and oven drying) compare to the rest minerals. The Z.P.C. of these synthetic minerals were 8.0-8.5, 7.5-8.0 and 5.5-6.0 for Fe-hydrous oxide A, B and Al-hydroxide, respectively.

• Textile Coloration and Finishing
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• v.15 no.1
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• pp.23-29
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• 2003

Dyeings of the most widely used to the synthetic fibers, namely polyamide and polyester, have been carried out using acid dyes and disperse dyes. The above mentioned dye types, and indeed all dyes onto substrates, rely on the reaction properties between the substrates and dye molecules. In terms of fastness properties, however, especially to washings, the satisfactory levels are not present in the results from acid and disperse dyeings. Thus, vat dyeings leaves a feasibility and are an alternative way to overcome the problem. Although attempts and works have been reported in early years, with little if any commercial achievement and success. In this context, to meet increased demands towards a high level of wash fastness from consumers and retailers, an attempt using vat dyes has been carried out in this work.