• Journal of Korean Society of Environmental Engineers
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• v.27 no.9
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• pp.946-951
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• 2005

In this wort plasma treatment was evaluated as an alternative clean desizing technology. Size materials such as PVA(polyvinyl alcohol), PACL(polyacrylic acid esters) and their mixture on PET(polyethylene terephthalate) fabrics were treated by $N_2$ and $O_2$ plasma. $O_2$ plasma was more efficient in size removal than $N_2$ plasma, and the removal of PVA was higher than that of PACL. SEM(scanning emission microscopy) pictures of the plasma treated samples directly proved the disappearance of sizing agents. After $O_2$ plasma treatment, the PET fabrics were subjected to conventional desizing process. Compared with untreated fabrics, the desizing effluent from the treated fabrics gave lower TOC, COD and $BOD_5$ values. This indicates plasma treatment not only serves to directly remove sizing agents but also offered several advantages by changing the chemical properties of sizing agents. Lastly, the effect of plasma desizing process on dyeing was examined using color difference and dyeing fastness tests. The CCM(computer color matching) results showed rotor difference between PET fabric desized by $O_2$ plasma treatment for 20 min and reference PET fabric desized by the conventional wet desizing process was around 1. This suggests the treated PET fabric can be directly subjected to dyeing process without any additional process. The plasma treated fabric also gave a good result of dyeing fastness so that grades of laundering, crocking, heat and light fastness were same or even better than the reference PET fabric did.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.12
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• pp.1337-1346
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• 2006

Soil humin is the insoluble fraction of humic materials and play an important roles in the irreversible sorption of hydrophobic organic contaminants onto soil particles. However, there have been limited knowledge about the sorption and chemical properties of humin due to the difficulties in its separation from the inorganic matrix(mainly clays and oxides). In this study, de-ashed soil humins($Hu_1-Hu_6$) were isolated from a soil residues(Crude Hu) after removing alkali-soluble organic fractions followed by consecutive dissolution of the mineral matrix with 2%-HF for 2 hr. The humin samples were characterized by elemental analysis and $^{13}C$ NMR spectroscopic method and their sorption-desorption behavior for 1-naphthol were investigated from aqueous solution. The results were compared one another and that with peat humin. $^{13}C$ NMR spectra features indicate that the soil humin molecules are mainly made up of aliphatic carbons(>80% in total carbon) including carbohydrate, methylene chain. Freundlich sorption parameter, n was increased from 0.538 to 0.697 and organic carbon-normalized sorption coefficient(log $K_{OC}$) values also increased from 2.43 to 2.74 as inorganic matrix of the soil humin removed by HF de-ashing. The results suggest that inorganic phase in humin plays an important, indirect role in 1-naphthol sorption and the effects on the sorption non-linearity and intensity are analyzed by comparison between the results of soil humin and peat humin. Sorption-desorption hysteresis were also observed in all the humin samples and hysteresis index(HI) at low solute concentration($C_e$=0.1 mg/L) are in order of Peat humin(2.67)>De-ashed humin(0.74)>Crude Hu(0.59).

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.10 no.1
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• pp.63-75
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• 2012

This paper gives some basic requirements and preferences of various geological environmental conditions for the final deep geological repository of spent nuclear fuel (SNF). This study also indicates how the requirements and preferences are to be considered prior to the selection of sites for a site investigation as well as the final disposal in Korea. The results of the study are based on the knowledge and experience from the IAEA and NEA/OECD as well as the advanced countries in SNF disposal project. This study discusses and suggests preliminary guideline of the disposal requirements including geological, mechanical, thermal, hydrogeological, chemical and transport properties of host rock with long term geological stabilities which influence the functions of a multi-barrier disposal system. To apply and determine whether requirements and preferences for a given parameter are satisfied at different stages during a site selection and suitability assessment of a final disposal site, the quantitative criteria in each area should be formulated with credibility through relevant research and development efforts for the deep geological environment during the site screening and selection processes as well as specific studies such as productions of safety cases and validation studies using a generic underground research laboratory (URL) in Korea.

• Applied Biological Chemistry
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• v.18 no.3
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• pp.123-144
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• 1975

This study has been carried out to investigate the translocation-illuviation status of iron and manganese, which are striking phenomena in paddy soils, in relation to its morphological characteristics, and to find out a method to identify illuvial layer of iron quantitatively. Determination of active iron and easily reducible manganese content in surface soils of lowland paddy (266 samples) in Korea were conducted. The examination has been made on relationship between morphological, physico-chemical properties of the representative paddy soils (9 series) and iron and manganese content of their horizons. The results are summarized as follows. 1. The poorer the drainage, the higher concentration of active iron and easily reducible manganese were found, and under same drainage condition, the more the sand, the lower the content of them. 2. Irrespective of soil texture and drainage, highly signignificant positive correlation was found between the contents of active iron ($\hat{Y}$) and clay plus silt in surface soils. $$\hat{Y}=0.3929+(0.05352\;X\;clay%)+(0.0001023\;X\;silt%){\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;I$$ No correlation, however, was found between clay content and easily reducible manganese concentration. 3. Significant positive correlation was obtained between active iron ($\hat{Y}$) and total iron (x) content in each profiles of all soil series. Obtained regression equation is as follows; $$\hat{Y}=0.361x-0.480(r=0.651^{**}){\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;{\ldots}\;II$$ On the other hand, easily reducible manganese concentration had a tendency to increase, not significantly, with increasing total manganese concentration. 4. Accumulation of iron and manganese generally can be found in paddy soils, but distinct accumulation was found under moderately well drained fine loamy and clay soils, while surface accumulation occurred under poor drainage without regard to soil texture. 5. Profile description or determination of active iron in each horizon were found to be insufficient to designate illuvial layer of iron. Therefore, identification of illuvial layer of iron based on the ratio of total iron and active iron, and concentration of active iron estimated by the content of clay plus silt (Equation 1 above) was thought to be reasonable. Also, manganese accumulation layer would be estimated by total manganese and easily reducible manganese content and their ratio.

• Journal of Applied Biological Chemistry
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• v.52 no.2
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• pp.58-64
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• 2009

Total polyphenol contents and antioxidative activity of water and ethanol extracts from Sea Buckthorn (Hippophae rhamnoides) leaves, branches (bough and twig) and roots were analyzed. The level of crude ash and crude protein in water extract of leaves, branches (bough and twig), and roots were shown to be a bit higher than ethanol extracts. Especially crude protein contents from water extract of leaves, bough, twig, and roots were 14.90, 18.60, 18.03, and 16.61% respectively. Total polyphenol content of ethanol extracts of all parts of Sea buckthorn was ranged from 106.33${\pm}$2.32 ${\mu}g/g$ to 147.78${\pm}$3.06 ${\mu}g/g$ showing higher amount than water extracts. To investigate antioxidative activity of Sea buckthorn, DPPH free radical scavenging activity, hydroxy radical scavenging activity, and SOD-like activity were analyzed. The results showed that the antioxidative activity of ethanol extracts was relatively higher than water extracts. The $IC_{50}$ values for DPPH free radical scavenging activity was ranged from 23.58${\pm}$0.84 ${\mu}g/mL$ to 59.35${\pm}$1.69 ${\mu}g/mL$. Compared to 68.85${\pm}$1.44% of SOD-like activity from L-ascorbic acid used as a control, the ethanol extract of Sea buckthorn branches showed relatively strong activity of 35.03${\pm}$2.33%. The highest hydroxy radical scavenging activity was shown as 66.12${\pm}$8.73% from ethanol extract of Sea buckthorn roots which was similar value to 72.47${\pm}$2.83% of L-ascorbic acid.

• Journal of Bio-Environment Control
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• v.24 no.3
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• pp.235-242
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• 2015

The objective of this study was to determine the effects of soluble potassium silicate by soil drenching application on watermelon growth, yield, and nutrient uptake. The potassium silicate rates were control (No potassium silicate), 1.63mM, 3.25mM, 6.50mM. The potassium silicate were treated 6 times (twice before fruit forming and 4 times after fruit forming per 7 day. Soil chemical properties, such as soil pH, EC, available phosphorus and silicate, exchangeable K, nitrate-N levels were increased after potassium silicate treatment, while the concentrations of soil organic matter, exchangeable Ca and Mg were similar to control. The growth characteristics of watermelon, such as stem diameter, fresh and dry weight of watermelon at harvest were thicker and heavier for increased potassium silicate treatment than the control, while number of node, and plant length were same for all treatments. With increased potassium silicate treatment, nutrient concentrations, such as P and K in the watermelon leaf at harvest were increased, N concentration in the leaf was decreased, and Ca and Mg concentrations in the leaf were same. Chlorophyll content was increased with increased potassium silicate application. The occurrence of powdery mildew was lower for the potassium silicate treatments than the control. Fresh watermelon weight for the potassium silicate treatments was 0.1 to 0.5kg per watermelon heavier than the control, sugar content was 0.5 to $0.6^{\circ}Brix$ higher than control, and merchantable watermelon was 2 to 4% increased compared to the control. These results suggest that potassium silicate application by soil drenching method in the greenhouse can improve watermelon nutrient uptake, merchantable watermelon and suppress the occurrence of powdery mildew.

• Magazine of the Korean Society of Agricultural Engineers
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• v.10 no.1
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• pp.1388-1393
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• 1968

Higher yield in rice paddies is greatly dependent on adequately balanced and timely supply of water. A majority of rice paddy in Korea is generally irrigated by rainfall, but in many cases it has to be supplemented by artificial irrigation for optimum rice culture. Although the water requirement of rice plant is far higher than that of other crops, submerged condition of rice paddy is not necessarily required. The moisture requirement of rice plant varies with its growing stages, and it is possible to increase the irrigation efficiency through reduction of water loss due to percolation in rice paddies. An experiment was conducted on the effectiveness of economical use of water by different irrigation period and different method of cultivation. The experimental plots were set up by means of randomized block design with three duplications; (a) Alltime submerged (b) Economically controlled, and (c) Extremely controlled. Three different irrigation periods were (a) Initial stage (b) Inter-stage, and (c) last stage. The topsoil of the three plots were excavated to the depth of 30cm and then compacted with clay of 6 cm thickness. Thereafter, they were piled up with the excavated top soils, leveled and cored with clay of 6cm thickeness arround footpath in order to prevent leakage. The results obtained frome the experiments are as follows; (1) There is no difference among the three experiment plots in terms of physical and chemical contditions, soil properties, and other characteristics. (2) Colulm length and ear length are not affected by different irrigation methdos. (3) There is no difference in the mature rate and grain weight of rice for the three plots. (4) The control plot which was irrigated every three days shows an increased yield over the all the time submerged plot by 17 persent. (5) The clay lined plot whose water holding capacity was held days long, needs only to be irrigated every 7 days. (6) The clay lined plot showes an increased yield over the untreated plot; over all the time submerged plot by 18 percent, extremely controlled plot by 18 percent, and economically controled plot by 33 percent.

• The Korean Journal of Pesticide Science
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• v.21 no.1
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• pp.97-105
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• 2017

This study was carried out to determine residual characteristics and to evaluate safety of bifenthrin, carbendazim and metconazole in minor crop, Angelica gigas Nakai. The test pesticides were sprayed onto the crop according to the combinations of spray days before harvest and frequency and then sampling was performed at the harvest day. Non-systemic pesticide bifenthrin was not detected in all samples, whereas systemic pesticides, carbendazim and metconazole, were detected from the crop in the range of from 0.14 to 0.49 and from 0.19 to 0.26, respectively. These results indicated that residual characteristics of the test pesticides in Angelica gigas Nakai were affected by their systemic properties. Also, residual concentration of carbendazim and metconazole in the crop was increased as more spraying frequency and spraying more closer to harvest day. And residual concentration of carbendazim in the crop on the last spraying day was 2.1 times higher than that of metconazole because nominal spraying dose of carbendazim was higher than that of metconazole by 1.9 times. The residue levels of the test pesticides in the crop were evaluated to be safe, considering their %ADIs were less than 0.9%.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.3
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• pp.302-307
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• 2002

To investigate difference of components changes in salt-fermented anchovy, Engaulis japonicus sauce during 18 months fermentation by tank size, various chemical properties were examined at 2$\~$3 months intervals. The contents of total and amino nitrogen, total ATP related compounds increased gradually during 18 months of fermentation, and showed higher content in salt-fermented anchor sauce produced by large tank scale (LTS) product than those of small tank scale (STS) product during fermentation. Hypoxanthine and uric acid were the most abundant in ATP related compounds, ranging from $81.1\%$ to $90.4\%$, The cross point of inosine (HxR) + hypoxanthine (Hx) and uric acid was faster in LTS with 10.3 months fermentation than in STS with 12.6 months fermentation. After 18month of fermentation, the LTS was rich in free amino acids, such as glutamic acid, alanine, aspartic acid, valine, Iysine in that order. On the other hand, the STS was rich in free amino acids, glutamic acid, aspartic acid, alanine, vsine, valine in that order. Absorbance at 453 nm were higher in STS than in STS, but was no difference the rate of increase during fermentation.

• Korean Journal of Soil Science and Fertilizer
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• v.11 no.4
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• pp.213-233
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• 1979

It is generally agreed that the country's population will grow up to the level of 52 million by the year of 2000 and that due the active growth of industry, urbanization and road constructions, sizable portion of existing arable lands will be utilized for other purposes than agriculture in near future. From 1966 to 1977, it was estimated that, the average annual conversion of arable lands to other uses, was 12,909 ha. If this trend persists, it is predicted that from 1978 to 1991 when the 6th Five Years Economic Development Plan will terminate, approximately 181,000 ha of arable lands will be converted for other uses again. On the other hand, it is certain that the increased population (39 million in 1981, 45 million in 1991, 52 million in 2001) and the changes in food pattern along with the enhancement of living standards will bring about the phenomenal increase in demands for not only the staple food but also the livestock products such as meat, milk and eggs, vegetables and fruits. These future increased demands for various foods, naturally mean the increased needs for the expansion of arable lands at the same time. It is predicted that, if more activities than present scale are not taken for the expansion of arable lands, the national food self sufficiency level will drop from 79% in 1977 down to 62% in 1991. To meet the increased food demands in future, there are several ways and means. These will include the increased land use intensity, elevation of unit area yield levels, minimization of conversion of arable lands to other uses and expansion of arable lands through the reclamations of idle hillside lands and tidal lands. Among these, the expansion of arable lands through reclamations of idle hillside lands and tidal lands are more positive measures to cope with the increased production of foods in future. The reclamation of hillside lands demands more attention because it needs more advanced technologies in agronomical and engineering aspects, larger scale fundings and integrated socioeconomic considerations. In agromical aspects, the thechniques for early improvement of chemical and physical properties of soils, proper soil conservation measures and rational cropping systems are of particular importance. As to the financial supports to encourage the farmings in hillside land, much bold fund inputs are essential for the construction of roads, installation of irrigation and drainage facilities, soil conservation mechanisms, which will ensure the stabilized farming with reasonable incomes in the newly reclaimed lands.