• Applied Chemistry for Engineering
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• v.33 no.1
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• pp.28-37
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• 2022

The lignite and bituminous coal are mainly used in thermal power plant. They exhaust green house gas (GHG) such as CO₂, and become deplete, thus require alternative energy resources. To solve the problem, the hydrochar production from biomass is suggested. In this study, both hydrothermal carbonization (HTC) and solvothermal carbonization (STC) were used to produce high quality hydrochar. To improve the reactivity of water solvent process in HTC, STC process was conducted using ethanol solution. The experiments were carried out by varying the solid-liquid ratio (1:4, 1:8, 1:12), reaction temperature (150~300 ℃) and retention time (15~120 min) using kenaf. The characteristic of hydrochar was analyzed by EA, FT-IR, TGA and SEM. The carbon content of hydrochar increased up to 48.11%, while the volatile matter decreased up to 39.34%. Additionally, the fuel characteristic of hydrochar was enhanced by reaction temperature. The results showed that the kenaf converted to a fuel by HTC and STC process, which can be used as an alternative energy source of coal.

• Korean Journal of Agricultural Science
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• v.38 no.1
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• pp.7-10
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• 2011

In order to develop the new Miscanthus varieties for biomass, characteristics of collected materials were surveyed. Also, they were treated with S-azide(Sodium-azide) and DES(dethyl sulfate) for promising lines and 0.2% Colchicine for polyploidy, respectively. CNU-J1 line induced with chemical, DES and S-azide treatment showed shorter than others in stem height and stem diameter. CNU-N1 line treated with 10 mM DES showed earlier than non-treated lines in flowering as 7days. Among selected lines, the CNU-J1 line was crossed with DB-1 selected as a superior line and their hybrid was expected to be high in biomass than others. Especially, CNU-W1 line treated with 2.5~5.0 mM DES showed heading in M1 generation.

• 한국약용작물학회:학술대회논문집
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• 2011.09a
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• pp.282-283
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• 2011

• 한국약용작물학회:학술대회논문집
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• 2011.04a
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• pp.384-385
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• 2011

• Journal of Nutrition and Health
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• v.16 no.3
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• pp.185-192
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• 1983

한국인과 한국산 가축의 selenium 영양상태를 파악하기 위하여 남한의 selenium 분포조사를 실시한 결과 전국 45개 지역 토양중 selenium 함량은 0.03 내지 0.24 ppm이였으며 중앙 동북 고산지대는 0.14-0.24 ppm으로 높았고 서해안 그리고 남해안은 0.03-0.06 ppm으로 비교적 낮았다. 전국 42개 지역에서 채취한 목초 (억새, 크로바 )는 0.036 ppm (0.02-0.13ppm )을 함유하고 있으며 콩, 보리, 쌀은 0.047, 0.033 그리고 0.033 ppm selenium을 각각 함유하고 있었다. 전국 23개 도시에 거주하는 204명의 사람에서 채취한 혈액에는 평균 $0.16\;{\pm}\;0.06{\mu}g/m1$ $(0.05-0.35{\mu}g/ml)$ selenium 함량을 갖었고 glutathione peroxidase 활성도는 평균 $13.0\;{\pm}\;1.7\;EU/mg$ homoglobin이었다. 남한에서 생산되는 곡류와 채소류에는 0.02 내지 0.04 ppm의 selenium을 함유하고 육류인 쇠고기, 돼지고기에는 $0.11\;{\pm}\;0.05$와 $0.14\;{\pm}\;0.03\;ppm$을 그리고 참치, 조기, 숭어, 마른멸치등에는 $0.50\;{\pm}\;0.02,\;0.42\;{\pm}\;0.09,\;0.20\;{\pm}\;0.02$ 그리고 $0.55\;{\pm}\;0.04\;ppm$ selenium을 각각 함유하고 있었다. 국민 1인당 하루 selenium 섭취량은 $42.3\;{\mu}g$이며 이중 71 %는 주로 곡류와 채소에서 충당하고 있다.

• Journal of The Korean Society of Grassland and Forage Science
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• v.15 no.4
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• pp.274-278
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• 1995

This experiment was conducted to know what does the cutting date have an effect on the chemical composition and nutritive yield of Miscanthus sinensis, in order to determine the optimum cutting date of the plant when it is utilized as roughage. Miscanthus sinensis growing natively in the summit of Sam Ak mountain(550m above sea level) was cut at 10 days intervals from 25 July to 15 October, 1988. Plant length and dry matter contents were generally increased with delayed cutting date. Crude protein contents of the plant cut on 5, 15, and 25 of September were 5.5, 5.2 and 5.1%, respectively. Cmde fiber contents was similar with cutting treatment and averaged 35.6%. Cmde protein yield was higher in September than in other cutting date. Yield of crude fiber were 8.3, 9.3 and 9.3t/ha on 5, 15 and 25 September, respectively. Ratio of Cmde protein yield to Crude fiber yield on 5 September tended to be higher than on 15 September and 25 September. These results suggest that the optimum cutting date of the Miscanthus sinensis for good quality forage seems early September.

• The Korean Journal of Ecology
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• v.18 no.4
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• pp.483-491
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• 1995

This study examined the relationship among catch-fire, burning, maximum temperature (MT), amount of combustion-heat (ACH), and combustive time (CT) in heating temperature treated with the same amount of each organ of Miscanthus. In the survey sites, about 19％ of the areaswere covered by Miscanthus types, and the dry weight of Miscanthus and debris on the ground were 1,164 and 178 g/㎡, respectively. At 350℃ and 400℃, the rise of temperature by Culm type (culms and ears) and Leaf type (leaves and debris) were 90℃ and 82℃, respectively. At 350℃, durning time (BT) of culms-200, ears-200, ears-200, leaves-200 and debris-200 was 0-10’30”, 0-07’40”, 0-04’20”and 0-02’40”, and that at 400℃ was 0-01’20”, 0-00’50” 0-00’35”and 0-00’30”, respectively. BT was shorter at higher temperatures, and BT of Leaf type was shorter than that of Culm type. The amount of samples consumed was as follows: Culm type (culms-200 and ears-200) was 14.6g and 12.6g more than Leaf type (leaves-200 and debris-200) at 350℃ and 400℃, respectively. The total amount of combustion-heat (TACH) of samples was 5,859.7 kcal. The amount of mean combustion-heat generated from sample at 350℃ and 400℃ differed little: 727.6 kcal (24.9％) at 350℃ and 737.3 kcal (26.0％) at 400℃.

• The Korean Journal of Ecology
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• v.23 no.5
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• pp.391-395
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• 2000

The vegetations of Hansan and Chubong islets in Tongyoungsi were investigated from April, 1997 to December, 1998 and a synthesis table was constructed. Based on the synthesis table, the vegetation was classfied into 6 communties: Pinus thunbergii community, Pinus densiflora community, Machilus thunbergii community, Chamaecyparis obtusa afforestation, Cryptomeria japonica afforestation, Miscanthus sinensis var. purpurascens community, and 3 subcommunities: Pinus thunbergii typical subcommunity, Quercus variabilis subcommunity, Carpinus coreana subcommunity. The vegetation of Pinus densiflora community around Jeseungdang area is well preserved. However the islet requirs the ecological restoration, and we suggest that the rare species such a Crypsinus hastatus, old trees of Machilus thunbergii and Pinus thunbergii, and the habitat for Machilus thunbergii and Camellia japonica must be preserved.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.7 no.1
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• pp.110-115
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• 2004

This experiment was conducted to investigate the effect of light intensities on the growth responses, carbohydrate contents and the characteristics of leaf gas exchange in Miscanthus sinensis and Pennisetum purpurascens. The plant height and leaf length were increased to about 30% in the sun. However, those were reduced severely in the shade, and leaf necrosis was also observed. The representative growth index and the dry weight of 2 species were 50% higher than shade and the rate was reduced according to the decrease of light intensities. Total carbohydrate contents showed very similar changes to that of dry weight. However, any notable influences were observed at above the light intensities of 250~500${\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ in the half shade. The size of spikes and the earliest spiking appeared in the sun and the spike color was decolorized as decreased in light intensities, irrespective of species. Photosynthetic rate of 2 species was 2 times higher in the sun than those in the shade, and it showed the typical photoresponses of sun plant. Stomatal conductances and intercelluar $CO_2$ concetration showed similar changes to that of photosynthetic rate. On the contrary, vapor pressure deficit was increased more in the shade than in the sun.

• Proceedings of the Korean Society of Disaster Information Conference
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• 2016.11a
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• pp.221-222
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• 2016

습지는 생태자원의 보고로 다양한 생물종의 서식지를 제공하며, 습지 생태계는 어느 생태계보다 생산성이 높다. 습지는 잦은 수위변동으로 인해 습지의 식물은 수위의 영향을 많이 받는다. 따라서, 식물종의 특징과 최적의 생육환경과의 관계를 규명하기 위해 수위에 따른 식물의 서식환경을 분석해야 한다. 본 연구에서는 자연생태계가 잘 발달되어 있는 남한강의 비내섬 습지에 대해 유황분석을 하였고 유황에 따른 유량을 모의하였다. 모의된 유량과 HEC-RAS 모형을 이용하여 유황별 홍수위를 산정하였으며, RAS Mapper를 이용하여 침수심과 침수구역을 모의하였다. 이를 통해 침수심에 영향을 많이 받는 식물의 서식환경을 분석하였다. 버드나무군락은 침수가 발생하지 않는 지역 및 0~0.8m의 침수심, 물억새군락은 침수가 발생하지 않는 지역 및 0~0.4m의 침수심, 쑥-망초군락과 달뿌리풀군락은 0~0.4m의 침수심, 그리고 환삼덩굴군락은 0~0.8m의 침수심이 발생하는 지역에서 서식하는 것으로 분석되었다. 본 연구의 결과는 유황에 따른 침수심에 대한 식생서식환경을 분석한 것으로 식생을 고려한 인공습지 조성이나 하천설계에 있어 기초적인 자료가 될 것으로 기대된다.