• Bulletin of the Korean Chemical Society
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• v.32 no.10
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• pp.3610-3613
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• 2011

CdS nanoparticles (NPs) were synthesized in an aqueous phase in order to investigate their spectral behaviors as efficient fluorescence resonance energy transfer (FRET) donors for various organic dye acceptors. Our prepared CdS NPs exhibiting strong and broad emission spectra between 480-520 nm were able to transfer energy in a wide wavelength region from green to red fluorescence dyes. Rhodamine 6G (Rh6G), rhodamine B (RhB), and sulforhodamine 101 acid (Texas red) were tested as acceptors of the energy transfer from the CdS NPs. The three dyes and synthesized CdS NPs exhibited good FRET behaviors as acceptors and donors, respectively. Energy transfers from the CdS NPs and organic Cy3 dye were compared to the same acceptor Texas red dye at different concentrations. Our prepared CdS NPs appeared to exhibit better FRET behaviors comparable to those of the Cy3 dye. These CdS NPs in an aqueous solution may be efficient FRET donors for various organic dyes in a wide wavelength range between green and red colors.

• KSBB Journal
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• v.14 no.5
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• pp.517-522
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• 1999

A green tea used in this experiment was cultivated at Bosung (Chonnam) and purchased from a domestic market. The extract at 5$0^{\circ}C$ water from the powder of green tea partitioned with chloroform and ethyl acetate. The resulting solution was further purified with a chromatographic column (4.6$\times$250 mm, 15${\mu}{\textrm}{m}$, Lichrospher 100RP-18). Finally separation was achieved on a $\mu$-Bondapak $C_18$(3.9$\times$300mm, 10${\mu}{\textrm}{m}$) column. The elution order of the catechin compounds contained in the green tea was EGC(Epigallocatechin, C(catechin), EC(Epicatechin), EGCG(Epigallocatechin Gallate) and ECG(Epicatechin Gallate). From the experimental results the mobile phase for isolating EGCG from the extract consisted of 0.1% acetic acid in water/acetonitrile, 87/13%(v/v). The flow rate of mobile phase was 1.0 $m\ell$/min, and UV wavelength was fixed at 280 nm. 121.3 mg of EGCG, higher than 98% of purity, was obtained from 5 g of dry green tea.

• Applied Microscopy
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• v.30 no.2
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• pp.165-172
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• 2000

To investigate the defensive effect of green tea against the lead toxicity, Sprague-Dewley rats (150 gm) were divided into 5 groups; the control group, the group treated with lead for 4 weeks (Group A-1), the group treated with lead and green tea for 4 weeks (Group A-2), the group treated with lead for 8 weeks (Group B-1), and the group treated with lead and green tea for 8 weeks (Group B-2). The lead acetate (500 ppm) was injected two times for one week into the abdomen and green tea solution (3 g/100 ml distilled water) offered freely. In the liver cell, The cristae of mitochondria were enlarged, the rough endoplasmic reticulum (rER) extended and many lysosome observed on the Group A- 1. The cristae of mitochondria were enlarged and many lysosome observed, but nucleus was normal on the Croup A-2. All of observed parts on the Group B-1 deeply wounded by lead than the group A-1. In the Group B-2, the mitochondria and rER were increased in number than the Group B-1 and the nucleus was observed normally.

• The Korean Journal of Mycology
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• v.18 no.2
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• pp.89-96
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• 1990

This study was conducted to find out the effects of Thiabendazole on controlling green mold causing serious damage to oyster mushroom, Pleurotus spp. during the cultivation. In vitro, the strains of oyster mushroom such as ASI 2018, 2072 and 2016 were inhibited by 500 ppm of the fungicide, but the strain of ASI 2001 and ASI 2070 was inhibited by 100 and 500 ppm on oatmeal agar, respectively. The mycelial growth of the oyster mushroom started to be inhibition by soak treatment at a 0.2g/1000 ml aqueous solution of the fungicide. When the oyster mushroom and green mold inoculated both or separately on the substrates of soak treatment, the green mold did not grow at all, but the oyster mushroom grown well. The maximum control effect of the green mold showed when $2g/m^2\;and\;5g/m^2$ of the fungicide was sprayed on the surface of substrates before pasteurization. The highest yield of the sporophores of oyster mushroom was obtained from $5g/m^2$ treatment.

• Korean Journal of Food Science and Technology
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• v.31 no.4
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• pp.1024-1028
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• 1999

Green tea infusions were prepared by extracting them with aqueous solution of different pHs and their physicochemical properties were analyzed. Yellowness, chroma and total color difference values were increased as pH increased. The content of total amino acids in the green tea infusion was not influenced by pH values. Total catechin contents of the green tea infusion extracted at pH 4.0, 5.0, 6.0 and 7.0 were 32.28, 31.84, 31.14 and 14.70 mg/g, respectively. Among the four catechins investigated, epigallocatechingallate and epigallocatechin are more unstable as the pH was changed from 6.0 to 7.0. As pH increased, the extraction of caffeine was also increased. In conclusion, extraction at low pH is preferred for the preparation of green tea infusion.

• Preventive Nutrition and Food Science
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• v.12 no.1
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• pp.35-39
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• 2007

This study was conducted to investigate the effects of soil selenium (Se) supplementation level on Se contents of green tea and milk vetch. Four different concentrations of sodium selenite ($Na_2SeO_3$) solutions (0.0, 3.3, 33.0 and 165.0${\mu}g/mL$) were prepared and one liter of each solution was well mixed with 10 kg of compost (cowpea soil) to give four different levels of Se-containing soil: $T_1$, 0; $T_2$, 33; $T_3$, 330; $T_4$, and 1,650${\mu}g$/100 g soil. Green tea plants and milk vetch were individually cultivated in those soils for 60 days. Se contents of freeze-dried green tea leaves were 6.87, 10.40, 12.04, and 20.19 ${\mu}g/g$, respectively; all of which were significantly different (p<0.05) from the others except for $T_2$ and $T_3$. The results showed that Se-contents of green tea leaves were increased 1.5$\sim$2.9 times as the Se level in the soil increased. Regression equation between Se contents in green tea (Y) and soil Se supplementation level (X) was: Y=0.007X＋8.857. However, Se contents in the milk vetch were increased significantly (p<0.05) more with the same treatments $T_3$ (74 ${\mu}g/g$) and $T_4$ (187$\mu$g/g) in comparison to those at $T_1$ (5.0 ${\mu}g/g$) and $T_2$ (12.0$\mu$g/g). The increases ranged from approximately between 2.4 to 37.4 times that of the control group. Regression equation between Se contents in milk vetch (Y) and soil Se supplementation level (X) was: Y=0.1063X＋15.989. The large difference of Se contents between green tea leaves and milk vetch would be attributed by the difference of protein contents between the 30% or higher protein-content of legumes and 15$\sim$20% protein of shrubs. The present study clearly indicates that green tea leaves and milk vetch can be enriched in selenium by supplementing the soil with Se. Therefore, Se-enriched green tea or milk vetch powder could be utilized as functional foods in Se-fortified green tea drinks or salads, or as food additives to enhance the daily intake of Se.

• Journal of the Korean Institute of Landscape Architecture
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• v.49 no.2
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• pp.101-112
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• 2021

In Korea, efforts have been made continuously to improve the environment of traditional markets concerning the issues of urban regeneration. In particular, many old cities and traditional markets face a lack of parking spaces. As a solution to this, attempts are being made to prepare underground parking spaces by designing urban planning facilities in three-dimensional ways and utilizing the upper part as a more meaningful space. This study is about the master plan to use the upper green area while creating an underground parking lot at 571 Sinmae-dong, Suseong-gu, Daegu. This green area was defined as a space with dual values, 'defensive green space' that needs to be ecologically protected, and 'active cultural space' where walking flows to the market and various events are concentrated. Three specific design strategies to balance these values were presented. First, to prevent indiscriminate occupation and damage by people and maintain a healthy green environment, securing the maximum amount of undivided green space in the site was suggested. Second, a space layout and a topography and planting patterns that can overcome the morphological characteristics of narrow and long-shaped sites enable the experience of abundant green spaces. Third, providing space to strengthen the connections with nearby urban facilities such as Sinmae Market and Gosan Library can also intensively accommodate cultural activities in various cities. This study has academic significance in providing implications for urban regeneration projects with similar contexts in the future.

• Journal of the Korean Chemical Society
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• v.52 no.2
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• pp.133-139
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• 2008

A new sensitive and selective spectrophotometric method for determination of trace amounts of cadmium using a polyvinyl chloride membrane containing bis-(2-ethylhexyl)phthalate as a solid phase extraction medium was investigated. Bis-(2-ethylhexyl)phthalate has used as a plasticizer. Cd(II) in an aqueous solution was trapped on the membrane in the form of colorful Cd (II)-I- - MG complexes (which MG is malachite green) and the cadmium complex was concentrated in the membrane. The absorbance of the green membrane was measured at 629 nm using a spectrophotometer, and then, the concentration of the cadmium was calculated using a calibration curve, which expressed the relationship between the Cd(II) concentration and the membrane absorbance after coloring for 25 min. The calibration curve was linear in the range of 10-760 μgL-1 cadmium in the test solution. The detection limit based on the 3Sbl criterion was 1.8199 μgL-1 and the relative standard deviations (RSD) were less than 4 % (n=5). The proposed method has been successfully applied to the determination of trace amounts of cadmium in the Tadjan River water sample (Sari-Iran), and the mean value of 28.7 μgL-1 was obtained.

• Membrane Journal
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• v.21 no.2
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• pp.141-147
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• 2011

The cation exchange membrane using TPA (tungstophosphoric acid) and the block co-polymer of polysulfone and polyphenylenesulfidesulfone was prepared for a separator of all-vanadium redox flow battery. The membrane resistance of the prepared cation exchange membrane in 1mol/L $H_2SO_4$ aqueous solution was measured. The membrane resistance of the prepared Psf-PPSS and Psf-TPA-PPSS cation exchange membrane was about $0.94{\Omega}{\cdot}cm^2$. Electrochemical property of all-vanadium redox flow battery using the prepared cation exchange membrane was measured. The measured charge-discharge cell resistance of V-RFB at 4 A decreased in the order; Nafion117 < Psf-TPA-PPSS < Psf-PPSS. The durability of membrane was earried out by soaking it in $VO_2{^+}$ solution and evaluated by measuring the charge-discharge cell resistance of V-RFB with an increase of soaking time. The prepared Psf-PPSS cation exchange membrane had high durability and Psf-TPA-PPSS cation exchange membrane had almost same durability compared with Nafion117.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.11 s.158
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• pp.1581-1588
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• 2006

The effects of removal of lignin or hemicellulose on the cottonizing and pulping characteristics of kenaf fiber were studied by comparing the conditions of non-cellulosic material contents, fiber lengths and dyeability. And the effects of lignin or hemicellulose on dyeability of the kenaf fiber using CI Direct Green 26 and CI Direct Red 81 were investigated. The results were as follows. The lignin contents decreased and the kenaf fiber became shorter and finer as the reaction time with sodium chlorite increased. The hemicellulose could be removed by treating sodium hydroxide solution to the fiber from which the lignin partly removed. The 80% of hemicellulose could be removed by 5% of sodium hydroxide solution in 5 minutes. But if lignin were not removed at all, hemicellulose could not be removed. The fiber lengths proper for apparel were obtained after treating sodium chlorite for 10-20 minutes and those for pulping were obtained after treating sodium chlorite for 40 minutes. The kenaf fibers from which lignin and hemicellulose partly removed were dyed with CI Direct Green 26 and CI Direct Red 81. Their dyeability increased as the removal rates of lignin increased. The ${\Delta}E$ values of kenaf fiber dyed with CI Direct Green 26 were lower than CI Direct Red 81.