• Korean Journal of Environment and Ecology
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• v.15 no.2
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• pp.118-124
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• 2001

본 연구의 목적은 도식에 식재된 두 침엽수조인 소나무와 잣나무 단목의 연간 $CO_2$, $SO_2$, $NO_2$ 흡수 및 $O_2$ 생산을 계량화하는 것이다. 자연환경 조건하에서 운반형 적외선가스분석기로 연간 $CO_2$교환율을 측정하여 $CO_2$흡수 및 $O_2$ 생산량을 그리고 $CO_2$와 SO$_2$EH는 $NO_2$간 흡수속도비를 적용하여 $SO_2$ 및 $NO_2$흡수량을 각각 산정하였다. 흉고직경을 독립변수로 단목의 생장에 다른 연간 $CO_2$흡수 및 대기 정화량을 추정하는 활용 용이한 방정식을 유도하였다. 연구대상 수목 중, 흉고직경 20cm인 잣나무는 연간 양 35kg의 $CO_2$, 11g의 $SO_2$, 19g의 $NO_2$를 각각 흡수하였고 25kg의 $O_2$를 생산하였다. 동일 직경의 소나무는 유도한 방정식을 적용하면, 연간 약 30kg의 $CO_2$, 9g의$ SO_2$, 15g의 $NO_2$를 각각 흡수하였고 22kg의 $O_2$를 생산하였다. 생상기간 중 단위엽면적당 $CO_2$흡수량은 잣나무가 소나무보다 적었으나, 단목의 연간 $CO_2$흡수 및 대기정화량은 총엽면적의 차이로 잣나무가 동일 직경의 소나무보다 많았다. 본 연구결과는 도시 침엽수의 연간 대기정화 가치를 용이하게 계량화학고 도시공간내 수목식재의 환경적 중요성을 홍보하는데 활용될 수 있다.

• KSBB Journal
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• v.10 no.2
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• pp.166-169
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• 1995

Spores of Trichoderma harzianum TCC 52445 for control of Rhlzocronia stem canker on potato were immobilized in various natural matrix, and germination rate and some rheological properties of the spore-matrix complex were Investigated. Germination rate of gelatin gel-spore complex and potato starch gel-spore complex were 2.8% and 2.9%, respectively, but hardness and cohesiveness of the gelstin gel-spoke complex were better than those of potato starch-spore complex. The hardness and cohesiveness were increased when the spores were immobilized in hybrid gelatin gel made by mixing several different types of natural matrix, but decreased their germination rate. Addition of corn steep liquor (1%) as spore nutrient in gelatin gel-spore complex was helpful for increasing the germination rate.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.31 no.1
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• pp.16-23
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• 2021

Lithium carbonate recovered from the waste solution generated during the lithium secondary battery manufacturing process contains heavy metals such as cobalt, nickel, and manganese. In this study, the recrystallization of lithium carbonate was performed to remove heavy metals contained in the powder and to increase the purity of lithium carbonate. First, the leaching efficiency of lithium carbonate according to pH in the aqueous hydrochloric acid solution was examined, and the effect on the recrystallization of lithium carbonate according to the equivalent and concentration of sodium carbonate was confirmed. As the equivalent and concentration of sodium carbonate increased, the recovery rate of lithium carbonate improved. And the SEM image showed that the crystal shape was changed depending on the reaction conditions with sodium carbonate. Finally, the high purity lithium carbonate of 99.9% or more was recovered by washing with water.

• Journal of the Korean Geotechnical Society
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• v.20 no.1
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• pp.29-36
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• 2004

Batch and column tests were performed to develop the design factors for permeable reactive barriers(PRBs) against the contaminated groundwater with ammonium from unsanitary landfill. Clinoptilolite, one of natural zeolites having excellent cation exchange capacity(CEC), was chosen as the reactive material. In batch test, the reactivity of clinoptilolite to ammonium was examined by varying the initial concentration of ammonium and the particle size of clinoptilolites. One gram of clinoptilolite showed removal efficiency about 80% against the ammonium except in very high initial concentration of 80 ppm, but the effect of particle size of clinoptilolite was not noticeable. Permeability test was performed for the specimens made of clinoptilolite and Jumunjin sand with 20 : 80 weight ratio. Flexible wall permeameter was employed far permeability test. The specimen containing the washed 0.42-0.85mm clinoptilolite showed the highest permeability of about $10^{-3}$/s. In column test, the reactivity of mixed materials against ammonium in flowing condition was examined with the landfill leachate. With the test results, clinoptilolite was found to be a suitable material for PRBs against the contaminated groundwater with ammonium.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.173-173
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• 2010

We proposed viewing angle switchable liquid crystal display(LCD) associated with fringe-field switching (FFS) mode with high aperture ratio characteristic. In the device, single pixel is separated into two regions, named as main pixel for displaying images and sub pixel for viewing angle control. In sub pixel region, add the common electrode on the top substrate and the initial alignment of liquid crystal is Hybrid Alignment Nematic (HAN) state. In conclusion, we suggested that the device has high aperture ratio characteristic because the LC directors are rotated in which viewing angle control region are generated fringe electric field.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.04a
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• pp.107-107
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• 2003

고품질 쌀 생산을 위하여 우리나라의 농가 및 미곡종합처리장의 벼 수확후 품질관리 현황 실태를 조사하여 일본, 미국, 중국 둥의 현황과 비교하였다. 중국의 경우 벼 수확은 대부분 인력에 의존하고 있으며, 일본은 산물형 콤바인 그리고 미국은 대형산물 콤바인에 의한 적기수확을 하고 있다. 우리나라의 경우에는 콤바인이 부족하고 벼 수확시기는 콤바인 운영자의 일정에 따라 결정되고 있으며 습논, 소면적 재배 논은 수확이 늦어져 적기 수확이 못되고 있는 실정이다. 한편 일본은 라이스센터, 컨트리엘레베타, 드라이스토아 등의 지원으로 적기 수확이 가능하고 건조기 건조율도 90%이상 2단계 상온 통풍체계로 수분함량 14.5~15.5%를 유지하고 있다. 우리나라를 제외한 일본, 중국, 미국의 저장시설은 대부분 대형저장 사이로에서 품종별, 산지별, 등급별로 구분한 저온저장 시스템을 갖추어 품질을 유지하고 있었다. 또한 도정시설도 고품질 도정시설을 완비하고 있으며 제현이나 정미과정에 색채선별기, 금속검출기, 활성화 장치 및 입형분리기 등을 통하여 불완전미가 제거하는 등 수확후 관리에 철저를 기하고 있다. 쌀의 등급화 및 유통과정를 보면 일본, 중국, 미국 등은 대부분이 품종, 산지 및 등급별로 브랜드화 하여 차별화 된 가격으로 판매되고 있으며 포장지에 쌀에 대한 정보를 최대한 표시하여 소비자가 선택하는데 도움이 되게 하여 유통되고 있다.

• Korean Journal of Ecology and Environment
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• v.39 no.4 s.118
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• pp.489-497
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• 2006

The feasibility of the Natural and Ecological Wastewater treatment System (NEWS) was examined for rural wastewater treatment in Korea. The intermittent trickling biofilter with high hydrophilic filter media was used for pretreatment for suspended solids and organic pollutants. The subsequent constructed wetland with porous granule materials was used for promoting nutrient removal. The results show that the removal efficiencies of the system were high with respect to the water quality parameters except COD. Even if the effluent from the biofilter did not meet the guidelines for wastewater treatment plant effluent in Korea in terms of $BOD_5$ and TN, the final effluent of the system meets the guidelines us to good performance of the constructed wetland. The regression analysis between pollutant loading rate and removal rate indicated that the system could have stable removal for SS, $BOD_5$, TN, and TP in the given influent ranges. The analysis in the winter period indicated that the wetland covered with transparent polycarbonate glass had the statble performance during the winter period dus to increase of temperature inside the wetland without any heating system. With the stable performance, effective poilutant removal, low maintenance, and cost-effectiveness, the NEWS could be considered as an alternative treatment system for decentralized regions and rural communities in Korea.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.1B
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• pp.101-105
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• 2010

Sunflower (Sunking4505) and Rape (Sunmang) are oil-seeds containing high oleic acid, and these are used for the production materials of bio-diesel and applying for phytoremediation. The effect of cadmium on germination rate and the growth of the plants is evaluated. Object seeds were placed in Cd (0, 1.5, 4, 12, 30, 60, 100, 150, 300, 500 mg/L) solutions for seven days, and germination rate, root length, shoot length, seedling length, and dry weight were observed. $IC_{50}$, seedling vigor index, and tolerance indices were computed, and data were statistically analyzed by Analysis of Variance (ANOVA). Germination rate as well as root, shoot, and seedling length decreased as the cadmium concentration increased except dry weight. The $IC_{50}$ of sunflower and rape are 112 and 10 mg-Cd/L, respectively. Only one of the sunflower seeds is germinated at 500 mg-Cd/L whereas rape seeds are not germinated more than 150 mg-Cd/L solution. Root has higher cadmium sensitivity than shoot, and sunflower has higher germination rate, growth, and seedling vigor index than rape. In case of tolerance indices, sunflower has lower value than rape at relatively low concentration, but has higher value at high concentration.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.2
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• pp.322-327
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• 1994

For the improvement of L-lysine productivity, development of the continuous fermentation system by a bioreactor assembly was attempted. Primarily, optimal conditions on the whole cell immobilization of Corynebacterium glutamicum ATCC21514 were studied and 76.2% of immobilization ratio was obtained when the cells were entrapped with 4% k-carrageenan showing 4.0kg gel strength. A bioreactor system was set up using the immobilized cells was applied for the continuous production of L-lysine. The results obtained under the optimum conditions were compared with those of the batchwise fermentation. Experimental results obtained from 14 day continuous fermentation showed 36.7% of sugar conversion to L-lysine while the productivity of L-lysine was disclosed as 4.96mg/ml mg-dry cell weight /hr which is 2.5times and 4.1 times higher than those of the batchwise fermentation by the intact cells and by the immobilized cells, respectively.

• Korean journal of applied entomology
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• v.30 no.1
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• pp.54-57
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• 1991

The width of head capsule of the beet armyworm, Spodoptera exigua (Hubner), was measured on the 5th generation larvae reared with artificial diet. The mean widths of head capsule of each instar were: 1st, 0.246 mm; 2nd, 0.35 mm; 3rd, 0.546 mm; 4th, 0.809 mm; 5th, 1.242 mm; and 6th, 2.185 mm. The coefficient of variation (%) of each instar were: 1st, 8.6; 2nd, 9.5; 3rd, 15.1; 4th, 11.2; 5th, 12.0; and 6th, 12.9. The growth ratio of each instar were: 2nd, 1.43; 3rd, 1.55; 4th, 1.48; 5th, 1.54; and 6th, 1.76. The fitness(%) to Dyar's law of the measurement of head capsule width were: 1st, 94.7; 2nd, 98.3; 3rd, 98.7; 4th, 94.8; 5th, 94.6; and 6th, 92.2. When the logarithm of the width is plotted against the number of instars, the calculated regression line is highly significient (Log Y = -0.819 + 0.1872X, $r^2$ = $0.9977*{**}$) and Dyar's constant was 1.54.