• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.107.1-107.1
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• 2011

최근 석유, 가스, 석탄을 비롯한 화석연료의 다량 사용으로 기후변화, 대기오염 등의 환경문제 및 자원 고갈의 우려 때문에 바이오매스는 중요한 화석연료 대체 에너지 자원으로써 큰 관심을 받고 있다. 바이오매스 자원을 에너지로 전환하는 방법 중 하나인 급속 열분해 공정은 산소가 없는 상태에서 바이오매스를 열적으로 분해하여 액상 상태의 생성물을 회수하는 공정으로, 증기상의 열분해 가스를 응축하여 회수하게 된다. 바이오매스의 급속 열분해에 관한 연구는 주로 바이오매스의 종류와 열분해 조건에 따라 회수되는 바이오 원유의 수율 및 물리 화학적 특성에 관한 연구가 수행되고 있으나, 열분해 가스의 응축에 관한 연구는 응축에 수반되는 복잡한 물리적 현상 때문에 미진하다. 따라서 본 연구에서는 바이오매스의 급속 열분해를 통해 생성되는 증기상의 열분해 가스의 응축 현상을 모사 할 수 있는 모델링 기법에 대해 연구하였다. 급속 열분해 공정을 통해 생성되는 바이오 원유는 수백개의 화합물로 구성되어 있으며, 동일한 바이오매스를 사용한 경우라도 공정조건에 따라 바이오 원유에 포함된 화합물은 달라진다. 따라서 본 연구에서는 바이오 원유의 주요 화합물인 water, propanal, butanal, pentanal, phenol, guaiacol, coniferyl alcohol, formic acid, acetic acid, propanoic acid, butanoid acid를 대상으로 열분해 가스의 응축을 모사하였다. 본 연구에서는 응축 모델링 기법의 검증을 위해 실험결과와 비교하여 정확성을 검증하였으며, 본 연구의 결과를 활용하여 응축 조건 변화에 따른 급속 열분해 가스의 응축률을 예측하고, 이를 이용한 응축 열교환기 설계에 유용하게 사용될 수 있을 것으로 판단된다.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.342-347
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• 2004

The deformation behavior of a $Zr_{55}Al_{10}Ni_5Cu_{30}$ bulk metallic glass under tensile loading at different range of strain rates and temperatures between 680 K and 740 K were investigated. The variation in the deformation behavior of $Zr_{55}Al_{10}Ni_5Cu_{30}$ bulk metallic glass which resulted from the crystallization induced during testing was reported. The$Zr_{55}Al_{10}Ni_5Cu_{30}$ bulk metallic glass has showed either homogeneous or inhomogeneous deformation depending on test condition. It exhibited a maximum elongation of about 560 % at the condition of $407^{\circ}C{\times}\;10^{-4}/s$. The flow behavior exhibited three different types and the flow stress became lower at higher temperatures and lower strain rates. The increase of the time elapsed during heating resulted in the partial crystallization of bulk metallic glass phase and eventually strain hardening and brittle fracture.

• The Korean Journal of Pesticide Science
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• v.20 no.3
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• pp.228-235
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• 2016

To investigate runoff losses of azoxystrobin from the field by rainfall, the influence of slope degree and length on runoff rate of azoxystrobin from the pepper field were measured. The SC type formulation was applied at the pepper field lysimeter in 2004 and 2005. The azoxystrobin washed down from plant were from 21% to 68% of what the applied. Concentrations of azoxystrobin in the first runoffs were less than $50{\mu}gL^{-1}$. Runoff losses were from 0.26% to 0.59% for 10% slope-plots, from 0.66% to 0.96% for 20% slope-plots, and from 0.84% to 1.78% for 30% slope-plots. Then they decreased with increasing slope-length. Runoff loss of azoxystrobin was closely related to volume of runoff, it was reduced by the ridge and the mulching effect.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.1
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• pp.44-50
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• 2010

This study was carried out to analyze physico-chemical properties and to determine stability of the 19 commercially available horticultural substrates in Korea by European standard methods (EN methods). The average pH, EC, T-N, $P_2O_5$ were 5.44, 0.62$dS{\cdot}m^{-1}$, 0.98% and 10.54$mg{\cdot}L^{-1}$, respectively. Dry bulk density and particle density were in the range of 124.47~243.16$kg/m^3$ and 2073.94~2249.99$kg/m^3$, respectively. Seventeen out of 19 horticultural substrates used in this study were 'very stable'. The other2 substrates were classified as 'stable'. Korea's own criteria of stability for the organic materials such as growing substrates and compost need to be developed so that farmers can use the optimum organic materials without anxiety.

• Current Research on Agriculture and Life Sciences
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• v.14
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• pp.49-60
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• 1996

In order to evaluate soil factors affecting the growth of Italian poplar, 23 areas planted with Italian poplar were surveyed. These 23 areas were classified into 3 categories, river-side, fallow-land and hill-side. The growth performance and soil factors for each area were investigated. The growth of Italian poplar at river-side was shown to be superior to that of fallow-land and fill-side. The rates of growth for fallow-land and hill-side are decreased by 8% and 21% compared to those of river-side, respectively. This suggests that plantation of Italian poplar at hill-side would not be profitable. Soil conditions of high productive area appeared liquid phase 20%, porosity 45%, water holding capacity 35 - 40%, soil hardness $1kg/cm^3$. pH 6 and rich in organic matter and total nitrogen. The results of factor analysis for soil factors affecting to Italian poplar growth that showed eigenvalue over 1 and communality value over 70% explained factor 1 : liquid phase, porosity and water holding capacity, factor 2 : pH and calcium, and factor 3 : soil hardness. This suggests that physical characteristics of soil is more important than chemical characteristics for Italian poplar growth. Multiregerssion analysis was conducted between diameter growth and soil hardness, liquid phase and calcium. The t-values for each independent variables showed significance at 1 - 10% level, but water holding capacity and pH are not significant. It is supposed that sites suitable to Italian poplar were alluvial plain of sandy loam or part of banking soil, well-ventilating soil, lower soil hardness, apposite soil moisture absorbing with about 100cm of ground water level, plentiful organic matters and total nitrogen and little acidity soil.

• Research in Plant Disease
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• v.18 no.3
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• pp.194-200
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• 2012

The objective of this research was to select effective fungicides for the control of Fusarium head bight (FHB) of wheat. We tested fourteen commercial fungicides against FHB in the laboratory and under field. Fludioxonil FS, Fludioxonil SC, and Benomyl + Thiram WP highly inhibited the mycelial growth of Fusarium graminearum on the medium while Oxine-copper WP, Thiophanate-methyl WP, and Copper hydroxide WP were not effective against FHB. To verify the disease control in field condition, we selected four fungicides such as Fludioxonil SC, Captan WP, Difenoconazole + propiconazole EC, and Metconazole SC. Their control efficacy on FHB disease severity of wheat was examined after the fungicide treatment twice (30th April and 10th May, 2012) in the two field locations (Iksan and Gimje). With no treatment, FHB severity was 45% and 33.7% in Gimje and Iksan, respectively. FHB disease incidence after fungicide treatment was between 0.3% and 2.2% in Gimje, showing over 95% FHB disease control. FHB disease incidence of fungicide-treated sector in Iksan showed slightly higher than Gimje but the control value of fungicides exhibited 87-90%. No side effect of the chemicals was observed in fungicide treatment. These results showed that four fungicides were effective in the FHB disease control in wheat.

• KSBB Journal
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• v.25 no.2
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• pp.155-166
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• 2010

Studies on the production of cell-wall bound innerpolysaccharides (IPS) (soluble ${\beta}$-D-glucan) have been performed by use of suspended myelial cultures of Inonotus obliquus. This product has promising potentials as an effective antidiabetic as well as an immunostimulating agents. As a first step to enhanced production of IPS, Intensive strain improvement programs were carried out by obtaining a large amounts of protoplasts for the isolation of single cell colonies. Rapid and large screening of high-yielding producers was possible because about fivefold higher amount of protoplasts ($2.3{\times}10^6$ protoplasts/mL) could be recovered with relatively high regeneration rates of $10^{-2}{\sim}10^{-3}$ by applying a modified filtration method, as compared to the previously used trapping method. A basic protocol necessary for UV-mutation of the protoplasts was also developed, resulting in several overproducing variants with good fermentation properties. Since the amount of IPS extracted from the mycelial cell walls of I. obliquus turned out to be almost constant per g DCW, increase in cell mass was considered the most important factor for the enhancement in IPS production. Therefore, attempts were made to screen mutant cells showing rapid mycelial growth rate in the final suspended cultures. Notably, the mutant strains showing an active cellgrowth in the preceding solid growth cultures were observed to produce higher amount of IPS in the suspended fermentations as well. A striking mutant, OBLQ756-15-5 strain, obtained from the survivors of a harsh UV-treated condition (97% death rate) was found to stably produce as high cell mass as 22 g DCW/L in the final fermentations. Currently, this strain is being tested for development of a scaled-up fermentation process for mass production of IPS.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.4
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• pp.370-374
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• 2007

This study was carried out to investigate the soil chemical and physical properties by annul variation and yield properties according to cropping rotation system of paddy field which was cultivated rice and soybean of each 1 year by turns, each 2 year by turns, 1 year of rice and 3 years of soybean and 4 years of soybean continuously. This study was conducted for 3 years from 2002 to 2004 in National Institute of Crop Science(NISC), Korea. Study was controlled by Shinpaldal 2 of midmatured species, sow a field with soybean by $60{\times}15cm$ in 27 May. Chemical fertilizer was spread in the field by N 3.0 kg, $P_2O_5 $ 3.0 kg, $K_2O$ 3.4 kg per 10a. This experiment was carried for increase the degree of self sufficiency of soybean from detect the better cropping system in paddy field. The results of the study were as follows; Soil prosity was increased 17.4% in each one year rotation and 21.8% in the sector of cultivated soybean for four years. Results was indicated that $5{\sim}9cm$ of stem length, $0.5{\sim}1.0ea$ of branch number and $3.5{\sim}7.0$ of SPAD value was decreased in the sector of cultivated soybean for $3{\sim}4$ years compared to $1{\sim}2$ year cultivated sector. The soybean yield was reduced 12.9%(222 kg/10a) in the 2 year cultivated sector and 21%(201 kg/10a) in the 3 year cultivated sector compare with paddy-upland switching cultivation(255 kg/10a). Root nodule weight and number was tend to decrease according to the increasing duration of cultivated soybean.

• Applied Chemistry for Engineering
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• v.26 no.4
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• pp.477-482
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• 2015

This study examined the adsorption characteristics of heavy metal ions ($Cr^{6+}$, $As^{3+}$) in an aqueous solution using recycled aggregate (RA) and recycled aggregate (RA)/steel slag (SS) composites. The RA and SS are favorable for the absorbent because it contains about 91% and 86.9%, respectively, which are some of the major adsorbent ingredients (CaO, $SiO_2$, $Al_2O_3$ and $Fe_2O_3$) for heavy metal. Kinetic equilibrium of $Cr^{6+}$ and $As^{3+}$ in RA and RA/SS composites reached within 180 min and 360 min, respectively. The kinetic data presented that the slow course of adsorption follows the Pseudo first and second order models. The equilibrium data were well fitted by the Freundlich model and showed the affinity order of $As^{3+}$ > $Cr^{6+}$. The results of $As^{3+}$ also showed that the adsorption capacity slightly increased with increasing pH from 6 to 10. Meanwhile, the adsorption capacity of $Cr^{6+}$ was slightly decreased. From these results, it was concluded that the RA and RA/SS composites can be successfully used for removing the heavy metals ($Cr^{6+}$ and $As^{3+}$) from aqueous solutions.

• Journal of Animal Environmental Science
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• v.10 no.3
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• pp.169-174
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• 2004

The present study investigated the possibility of applying the fermented swine liquid manure handled with TAO system to hydroponic cultivation. The fermented swine liquid manure (FLM) used for the study was in low concentration of phosphoric acid (P). Hence, when doing hydroponic cultivation, the concentration of P and K was supplemented. The concentrations of N, P, and K in compensated FLMs were as fellows; (a) N 58mg/1, P 0.5mg/1 and K 31 mg/1 for FLM-1, (b) N 58mg/1, P 31 mg/l and K 39mg/1 for FLM-2, and (c) N 58mg/1, P 31 mg/1 and K 61 mg/1 for FLM-3, respectively. For hydroponic cultivation, it was possible to use diluted solution by 100 times through experiment of germination index. According to the experiment using lettuce, the compensated FLMs with P and K were superior in leaf width, yield and dry weight to FLM without any treatment. Therefore, it is necessary to supplement some nutrition before applying. In conclusion, it is highly estimated that the fermented swine liquid manure can be ap-plied to hydroponic cultivation. It is also necessary to conduct further researches related to nutritional compensation depending on the vegetables.