• 한국자원식물학회지
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• 제13권2호
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• pp.95-103
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• 2000

토성 및 토양수분에 따른 시호근의 생육특성과 saikosaponin함량 및 항산화효소 활성 변화를 조사해 본 결과, 수분과다 토양에서 는 삼도시 호는 장수시호보다 생육 억제정도가 매우 높았고, 건물중은 과습, 적습, 과건 재배 순으로 높았고, 수분조건에 따른 토성별로는 과건은 식양토, 사양토, 사토 순으로, 적습과 과습시는 사토, 사양토, 식양토 순으로 높았다. 토양수분조건별 saikosapon a, d, c함량은 과건, 적습, 과습 순으로 높았고, 토성간에는 사토, 사양토, 식양토 순으로 높았다. POD 활성은 지상부는 장수시호가 삼도에 비하여 매우 높았고, 토양 수분함량간에는 장수는 과건, 과습, 적습 조건 순으로 높았으나, 삼도시 호는 과건, 적습, 과습 순으로 높았다. SOD활성은 지상부와 지하부 공히 장수시호가 높은 경향이나, 수분조건별로는 과건, 과습, 적습순으로 높았으며, 건조상태의 경우 두 품종 모두 사토에서 높았다. 시호에서 뿌리의 Saikosaponin함량과 POD 및 SOD 함량과는 정의상관을 나타내는 경향이었고 줄기 및 뿌리길이와 POD함량과는 부의 상관을 나타내었다.

• Journal of Microbiology and Biotechnology
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• 제20권7호
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• pp.1114-1120
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• 2010

A chitosan-degrading fungus, BSF114, was isolated from soil. The culture preparation showed strong chitosanolytic enzyme activity at an optimum pH of 4.0 and optimum temperature of $60^{\circ}C$ after 36-40 h fermentation. The rapid decrease in the viscosity of the chitosan solution early in the reaction suggested an endo-type cleavage of the polymeric chitosan chains. To identify the isolated fungus, molecular biological and morphological methods were used. The fungal internal transcribed spacer (ITS) region 1 was amplified, sequenced, and then compared with related sequences in the GenBank database using BLAST. The phylogenetic relationships were then analyzed, and the results showed that the fungus belongs to Aspergillus fumigatus. Morphological observations were also used to confirm the above conclusion. The chitooligosaccharides (COS) obtained through hydrolyzing the colloidal chitosan showed that A. fumigatus BSF114 is suitable for degrading chitosan and producing chitooligosaccharides on a large scale. High concentrations of the COS (1,000 and 500 ${\mu}g/ml$) significantly proliferated mice marrow cells.

• 한국대기환경학회지
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• 제6권2호
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• pp.183-191
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• 1990

To check the possible transportation of gaseous air pollutants with the particles of yellow sand in the movement of air masses during the Yellow Sand Phenomenon, the concentrations of such air pollutants as TSP, $SO_2, CO, NO_x, O_3 and N-CH_4$, and wind wpeed were measured during the Yellow Sand Phenomenon (April 8 $\sim 10, 1990) and they were compared with those during the normal times in Korea. Meanwhile dust color of the samples during the Yellow Sand Phenomenon was the color of sand, that during the normal times was dark-brown. The concentrations of dusts; water soluble components, and metallic components of soil-originated elements during the Yellow Sand Phenomenon were higher than those during the normal times. While the metallic components in the dusts during the Yellow Sand Phenomenon were from soil-originated elements, those during the normal times were of both soiloriginated and sea-originated elements. The change of hourly concentrations of air pollutants showed bi-modal distribution during the two periods. Generally, the concentration levels of air pollutants during the Yellow Sand Period were higher than those during the normal times. Although similarity was observed in the primary sources, differences were observed in the dynamics of the secondary sources due to chemical reactions of the air pollutants during the two periods.

• 생물환경조절학회지
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• 제8권1호
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• pp.1-8
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• 1999

This study was carried out to estimate the warmed water irrigation and the warmed soil efficiency on protected cultivation of cucumber in winter season. The water of 28$^{\circ}C$ was continuously supplied for soil warming and that is $25^{\circ}C$ for warmed water irrigation. Cucumber growth was analyzed when tile soil kept up the optimum temperature in the root zone. The cucumber growth are compared with the warmed soil plots. isolated warmed soil plots and non-warmed soil plots. The cucumber growth in warmed soil plots and isolated warmed soil plots were 20~50% higher than non-warmed soil plots compare to that by the warmed irrigation. In the non-warmed soil plots, the stem diameter and the number of leaves in the warmed water irrigation plots are 10% higher than those in the normal water irrigation plots. The yields in isolated warmed soil plots were 37~38% higher than non-warmed soil plots and those in warmed soil plots were 85~96% higher than non-warmed soil plots. The fruit length, weight and diameter in warmed soil plots were 15% higher than those in the non-warmed plots.

• Geomechanics and Engineering
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• 제20권3호
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• pp.207-220
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• 2020

Clay soils have a big potential to become contaminated with the oil derivatives because they cover a vast area of the earth. The oil derivatives diffusion in the soil lead to soil contamination and changes the physical and mechanical properties of the soil specially clay soils. Soil stabilization by using new material is very important for geotechnical engineers in order to improve the engineering properties of the soil. The main subjects of this research are a- to investigate the effect of the cement and epoxy resin mixtures on the stabilization and on the mechanical parameters as well as the microstructural properties of clay soils contaminated with gasoline and kerosene, b- study on the phenomenon of clay concrete development. Practical engineering indexes such as Unconfined Compressive Strength (UCS), elastic modulus, toughness, elastic and plastic strains are all obtained during the course of experiments and are used to determine the optimum amount of additives (cement and epoxy resin) to reach a practical stabilization method. Microstructural tests were also conducted on the specimens to study the changes in the nature and texture of the soil. Results obtained indicated that by adding epoxy resin to the contaminated soil specimens, the strength and deformational properties are increased from 100 to 1500 times as that of original soils. Further, the UCS of some stabilized specimens reached 40 MPa which exceeded the strength of normal concrete. It is interesting to note that, in contrast to the normal concrete, the strength and deformational properties of such stabilized specimens (including UCS, toughness and strain at failure) are simultaneously increased which further indicate on suitability and applicability of the current stabilization method. It was also observed that increasing cement additive to the soil has negligible effect on the contaminated soils stabilized by epoxy resin. In addition, the epoxy resin showed a very good and satisfactory workability for the weakest and the most sensitive soils contaminated with oil derivatives.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2004년도 춘계학술발표회
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• pp.667-671
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• 2004

The purpose of this paper is to study on the construction of environmentally friendly roadbed by reinforcing type soil solidification agent. The soil amendment agent used in this study is friendly to the environment, and has a function of soil-cement-agent solidification. The soil amendment agent was admixed with reinforced fiber material for enhancement of strength and durability of roadbed. The project of trial field test of roadbed construction with special reinforcing soil treatment agent was performed in Gyunggido on December 2003. A series of field and laboratory experiments including unconfined compressive strength, permeability were carried out to investigate the physical and mechanical characteristics of solidified roadbed treated by this reinforced solidifying agent. The results of this research showed that the roadbed using normal and poor soil could be efficiently constructed by treatment of this reinforcing type solidification agent admixed with fiber material.

• 한국환경농학회지
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• 제17권3호
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• pp.200-204
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• 1998

상하수처리과정에서 다량 발생하는 슬러지를 소성처리에 의해 생산한 인공토양의 자연에 안전한 환원가능성을 검토하기 위하여 인공토양의 이화학적 특성을 분석하여 밭토양과 비교하였다. 사용한 하수슬러지는 경기도지역의 하수종말처리장에서 그리고 상수슬러지는 경남지역에서 각각 수거하여 인공토양을 생산하였으며, 생산한 인공토양의 분석결과를 요약하면 다음과 같다. (1) 인공토양의 입도분석에 의하면 모두 모래로 분류되었으며, pH는 첨가제인 석회의 영향으로 높아서 알카리성을 띠었고, 투수성은 매우 우수하였다. 이러한 특성들은 인공토양을 적절히 혼합사용할 경우에 산성토양의 중화나 배수불량지역의 투수성개선등의 토양개량효과를 기대할 수 있을 것이다. (2) 저온소성시킨 인공토양은 유기물성분, 질소성분, CEC등이 밭토양에 비하여 높았으며 인성분은 약간 높은 정도이었다. 입장의 크기는 굵은 모래정도이었으며 비중은 밭토양에 비하여 낮은 편이었다. 저온소성한 인공토양은 조경분야의 토양개량재나 매립장의 복토재등으로 사용을 검토중이다. (3) 고온소성시킨 인공토양은 소성과정에서 유기물과 질소성분등이 연소되어 유기물성분, CEC, 비중, 질소성분이 밭토양에 비하여 모두 낮았다. 입자의 크기는 조절이 가능한데 본 연구에서 생산한 크기는 난석(蘭石)정도의 굵기이었다. 고온소성한 인공토양은 난석(蘭石)이나 오염물질의 흡착재등으로 사용을 검토중이다. (4) 중금속성분의 분석결과에 의하면 저온소성한 인공토양에서 구리성분이 토양환경기준을 약간 상회하나 나머지는 모두 엄격한 농경지에 대한 기준치보다 낮았다. 따라서 인공토양만을 사용하여 농경지를 조성하여도 중금속에 의한 오염가능성이 작은데, 기존의 토양에 토양개량재로서 일부 혼합하였을 경우에는 기존토양의 낮은 중금속농도에 의하여 희석되어 중금속에 의한 환경오염 우려는 거의 없을 것으로 판단된다. (5) 본 연구방법에 의한 슬러지의 인공토양생산방법을 본격적으로 적용하기 위해서는 경제성 개선, 다양한 성분의 슬러지에서도 신뢰할 만한 안정성 확보, 그리고 작물실험을 통한 안정성 검증등의 추가연구가 계속되어야 할것으로 생각된다.

• 한국토양동물학회:학술대회논문집
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• 한국토양동물학회 1997년도 총회 및 춘계학술대회
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• pp.2-4
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• 1997

This report includes 4 Part. I the characteristic of chinese Arachnological research; II, Systematic studies on Araneae we made in resent years; III. The survey of ecological study of Chinese Arachnology ; IV. Biocemical study of the venom and silk proteins of spiders.

• 한국환경농학회지
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• 제15권3호
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• pp.341-347
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• 1996

인공산성비 다음에 처리된 일반비가 배추, 무, 콩의 생육 및 토양 화학성에 미치는 영향을 구명하기 위하여 인공산성비(pH 2.7)를 5mm, 10mm를 살포한 후 일반비를 각각 0, 5, 10mm 씩 살포하는 처리를 3일 간격으로 배추와 무는 20회, 콩은 42회 실시하여 작물의 가시적 피해증상, 엽록소 함량, 수량 및 수량과 관련된 특성, 식물체 및 토양의 무기 양분 함량 등을 분석 조사한 결과는 다음과 같다. 1. 배추, 무, 콩의 가시적 피해정도는 인공산성비 처리량이 많을수록 심한 편이었고, 일반비의 처리량이 많을수록 감소되었다. 피해증상은 잎이 담갈색, 연록색으로 변하고, 황백색의 괴사 반점이 생기면서 잎 가장자리가 위축되었다. 2. 엽록소 함량은 배추, 무, 콩 모두 인공산성비 5mm보다 10mm 처리에서 높았고, 인공산성비 처리 후 일반비 처리량이 많을수록 높았다. 3. 배추, 무, 콩 등의 수량은 인공산성비 처리량이 많을수록, 또 인공산성비 살포 후 일반비 처리량이 많을수록 증가되었다. 4. 식물체중 무기양분 함량은 일반비 처리량에 따른 일정한 경향이 없었으나, 무와 콩의 황 함량은 인공산성비의 처리량이 많을수록 높았다. 5. 시험 후 토양의 화학성은 배추, 무, 콩 모두 토양 pH는 다소 감소하였고, 질소와 황 함량은 증가되었으며, 유기물, 인산, 치환성 칼슘, 마그네슘 및 칼리 함량 등은 일정한 경향이 없었다.

• Structural Engineering and Mechanics
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• 제33권1호
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• pp.67-77
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• 2009

The soil response calculation is described, by which, threw the fictive path of stress, the stress-deformation diagrams are determined, considering the nonlinear soil behavior. The calculation are lead incrementally, by which is shown that in the presented soil model (modified Cam Clay), considering the influence of overconsolidated soil pressure OCR, the number of calculation steps may, but not necessarily, have a sufficient influence on the value of failure load and definite soil deformation. The simplicity and the practicalness of the procedure, the enables modeling the complex relations in soil.