• The Korean Journal of Ecology
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• v.8 no.3
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• pp.163-169
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• 1985

The composition rates of litters were studied at Camellia japonica forests in Koje-Do and Haenam, and at Quercus acuta, Quercus acutissima, Cryptomeria japonica, and Chamaecyparis abtusa forests in Haenam. Total amounts of nitrogen, phosphorus, potassium, calcium, and sodium in litter samples were measured and the relation between these amounts and decomposition rate was studied. Annual litter production were rarely different at each forest in Haenam. The amount of accumulated organic matter was about 4 times greater at C. japonica forest in Koje-Do than at the C. japonica forest in Haenam. These amounts were 5, 282.1 $\pm$ 1, 026.03g/m2 in Koje-Do and 1, 420.7 $\pm$ 384.77g/$m^2$ in haenam. The decomposition rate were rarely differnet at each forest in Haenam, but the rates showed great difference at C. japonica foreests in Koje-Do and Haenam. The rates were 0.093 and 0.313 at C. japonica forests in Koje-Do and in Haenam respectively. The sodium contents were 0.472% and 0.229% on L layer and on Css layer of C. japonica forest in Koje-Do, while they were 0.034% and 0.043% on L layer, and on Css layer of C. jpaonica forest in Haenam. It is sugested that much difference in the salt contents in the forest floor was present from the results of sodium content measured at each site, and that the decomposition rate was affected by the much concentration of salt in Koje-Do.

• Natural Product Sciences
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• v.17 no.4
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• pp.315-320
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• 2011

Routinely applicable HPLC assay procedures for the ganglioside content in various deer antler preparations were established through the creation of a UV-absorbing chromophoric substance - trans-${\alpha},{\beta}$-unsaturated-hexadecene-aldehyde - from the sphingosine moiety in ganglioside molecules by two step chemical reactions. In order to guarantee the assay's accuracy and sensitivity, the HPLC-assay procedure adopted internal reference procedures by mixing cis-${\alpha},{\beta}$-unsaturated-hexadecene aldehyde[V] or cis-3-heptadecene- 1,2-diol[IV] to assay samples. The internal reference compound [IV] or [V] was synthesized in our laboratory starting from mannitol-diacetonide through three or four step organic reactions. This new HPLC-assay procedure was successfully applied to deer antler extracts with good dose-dependent calibration curves at the picomole level of gangliosides.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.174.1-174.1
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• 2011

Biogas production and utilisation is an emerging alternative energy technology. Biogas is produced from the biological breakdown of organic matter through anaerobic digestion. Biogas can be utilized for various energy services such as heating, electricity generation and vehicle fuel. Especially, to be utilized as vehicle fuel, raw biogas needs to be upgraded, that is, mainly the removal of carbon dioxide to increase the methane content, up to more than 95% in some cases, similar to the composition of fossil-based natural gas. Biogas fuelled vehicles can reduce $CO_2$ emission by between 75% and 200% compared with fossil fuels. Biomethane development is largely driven by national initiative and predominately by concerns for national air pollution and waste management. Recently, biogas projects for vehicle fuels by some companies are ongoing and Korea government also announced investment to develop biogas as a transport fuel. Therefore, the aim of this study is to examine the feasibility of biomethane as a transport fuel in Korea. In this study, we investigated quality characteristics, quality standard and upgrading technology to use vehicle fuel of transport sector in Korea.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.05a
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• pp.46-51
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• 2000

Environmental quality regulations are used to establish the maximum permissible concentrations of heavy metals before a site can be deemed to be polluted or contaminated. This paper compares the results obtained by 0.IN HCl extraction and acid extraction method(HNO$_3$+HClO$_4$.HCl). The leaching efficiency of 0.1N HCl extraction is directly proportional to the final pH of leachate, due to the different solubilities of the heavy metals at different pH values, The severe differences between 0.1N HCl-extractable and total metal contents result mainly from the buffering effect of carbonates, present in sediment. samples. Application of sequential extraction experiments to some sediments collected from gully pot in Seoul illustrates a much stronger scavenging effect by Fe and Mn-hydroxides, carbonates and organic phases. As deduced from both sequential extraction and leaching experiments, the relative mobility of heavy metals is found to be: Mn>Zn>>Co>Cd>>Cu>Pb>Cr>Fe, in spite of large differences in heavy metal content and localization. Changes in the physicochemical environments (such as acidification) caused by a traffic accident may result in the severe environmental pollution of heavy metals of surrounding area( surface water and rivers).

• Economic and Environmental Geology
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• v.28 no.2
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• pp.147-154
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• 1995

Coal fly ashes collected from the Samcheonpo and the Seocheon Power Plants were analyzed for major and minor components and heavy metals such as As, Cd, Co, Cr, Cu, Ga, Hg, Mo, Ni, Pb, Sb, V and Zn in order to suggest basic data to apply coal fly ash as fertilizer or soil ameliorator. The specific gravity of the samples was less than 2.0, and amounts of organic matter range from 5.0% to 12.3%. The identified minerals by XRD were mainly quartz, mullite and pyrite in anthracite coal, and mainly quartz and mullite in bituminous coal. Generally, the contents of heavy metal elements analyzed were lower less than those of soil, though higher in some samples. Element couples of some elements( e.g., As-Mo, Zn ; Mo-As, Sb, V, Zn ; Sb-Zn ) show positive correlations with each other, but the high correlations of toxic elements such as As, Pb, Cd and Hg indicate to give attention to apply coal fly ash as fertilizer or soil ameliorator.

• 레미콘
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• no.10 s.69
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• pp.2-11
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• 2001

This paper describes the feasiblity of recycling sewage dredged soils as fine affrefate. This paper describes the feasibility of recycling sewage dredged soils as fine aggregate. The specific gravity of the dredged soils was smaller than that of sand due to the effect of dredged sludge. However, the grain size distribution of the dredged soils is relative well graded, and the results of the heavy metal concentration from the leaching test of the dredged soils was significantly lower than the requirements of the allowable criteria. Therefore, the effect of recycling of dredged soils on environment the as fine aggregate was negligible. Also, the specific gravity of the dredged and washed soils was similar to that of sand, and the dredged and washed soils for the most part showed lower heavy metal leaching characteristics than those of dredged soils, Also, the results of the study for evaluation the recycling feasibility of dredged and washed soils as fine affrefate. The organic impurity content of the dredged and washed soils was lower than the requirements of the Korean industrial Standards, and the mortar compressive strength using the washdredged soils also met those of the Korean industrial Standards. And, the strengths of the dredged and washed soils were over 95% of those of the NaOH-treated samples. Therefore, it is expected that the dredged soils will be able to be an alternative for fine aggregate.

• Magazine of the Korean Society of Agricultural Engineers
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• v.45 no.5
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• pp.77-84
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• 2003

Recent advances in remote sensing techniques provide the potential for monitoring soil color as well as soil moisture conditions at the spatial and temporal scales required for detailed local modeling efforts. Soil moisture as well as soil color is a key feature used in the identification and classification of soils. Soil spectral reflectance has a direct relationship with soil color, as well as to other parameters such as soil moisture, soil texture. and organic matter. We evaluate the influence of seven soil properties, soil color and soil moisture, on soil spectral reflectance. This paper presents the results obtained from the ground-truth spectral reflectance measurements in the 300-1100 nm wavelength range for various land surfaces. The results suggest that the reflectance properties of soils are related to soil color, soil texture, and soil moisture. Increasing soil moisture content generally decreases soil reflectance which leads to parallel curves of soil reflectance spectra across the entire shortwave spectrum. We discuss the relationships between the soil reflectance and the Munsell Soil Color Charts which contain standard color chips with colors specified by designations for hue, value, and chroma.

• Analytical Science and Technology
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• v.5 no.1
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• pp.25-31
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• 1992

A benzene synthesizer was manufactured and has been used for the treatment of the various samples such as wood, charcoal, shell and soil for radiocarbon dating using liquid scintillation counter. The experimental conditions were optimized in each successive step of the synthesis of carbon dioxide, acetylene and the final product of benzene. Fifteen hours operation of the benzene synthesizer leads to product yields consistently in excess of 85% based on the content of calcium carbonate for the organic samples. Purity of the synthesized benzene was measured to be more than 99.9% by GC/MS.

• Journal of Environmental Impact Assessment
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• v.10 no.2
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• pp.85-98
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• 2001

This study was conducted to investigate the geochemical factors governing the distribution of heavy metals(Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in the marine surface sediment samples collected from the Samcheonpo coal-fired power plant. Variations of absolute metal concentrations were related to those in textural and/or carbonate and organic matter content. Most elements, except for Pb, showed generally lower contents compared with the average shale concentration, and the effect of anthropogenic input appeared to be minimal in the sediments. Computations of LF%(labile fraction) and EF(enrichment factor) based on all trace metal data indicated the presence of mineralogical control for Co, Cr, Cu, Ni, and Zn, and anthropogenic contamination for Pb, which needs to be considered in the design of long term monitoring programmes.

• Journal of the Korean Society of Food Culture
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• v.35 no.5
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• pp.450-458
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• 2020

This study examined the optimal temperature and time conditions to maintain high quality Dongchimi during the fermentation and storage period. Dongchimi was fermented at low (5℃), medium (10 and 15℃), and high (20℃) temperatures until the acidity reached 0.2, 0.3, and 0.4%. respectively. From the consumer's preference test enrolling five consumers, Dongchimi fermented at 15℃ until an acidity of 0.3% (for approximately six days) was evaluated to be the optimal status because of its high score of overall acceptance, taste, and odor of consumers. To determine the optimal storage temperature of fermentation, Dongchimi was stored at three different temperatures (-1, 2, 5℃) for four weeks after fermenting at 15℃ for six days. During the storage period, most of the physicochemical properties (pH, acidity, reducing sugar content, and organic acid) and microbiological properties changed significantly in the 2 and 5℃ groups, resulting in a significant change in descriptive sensory analysis of Dongchimi. These results indicate that fermentation at 15℃ and storage at -1℃ for Dongchimi enables it to maintain the best quality for a long time.