• Macromolecular Research
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• 제16권6호
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• pp.570-573
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• 2008

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• 한국환경복원기술학회지
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• 제19권1호
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• pp.185-193
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• 2016

Purpose of this study is to classify damaged lands according to the cause of the damage and their influences based on characteristic of the damaged lands in DeMilitarized Zone(DMZ) area, and utilize this study as a fundamental study for establishment of ecosystem restoration system. Literature review and field survey have been conducted to review the damage status of DMZ area. For field survey, first year and second year have been conducted, in which type of the damage has been reviewed in this study. In the result, types of damage have been classified into 6 categories: 'alteration of initial landform', 'loss of surface layer', 'land pollution', 'alteration of soil chemical property', 'decline of vegetation', and 'invasion of foreign species'. Restoration for each damage type is as following. First, for alteration of initial landform, the land is restored to the original landform prior to the damage and connection to surrounding ecosystem is considered. Second, for loss of surface layer, lost surface layer is restored or further loss is prevented with stabilization. Third, for land pollution, source of the pollution is eradicated or self-circulation with purification of polluted land is encouraged. Fourth, for alteration of soil chemical property, soil is restored of its original property with eradication of the pollution source and improvement of soil. Fifth, for decline of vegetation, current vegetation and anticipated alteration in future are considered and number of wild species is to be increased based on structure and characteristic of nearby vegetation. Sixth, for invasion of foreign species, prevention of dominance by risky species and facilitation ecological stability with ecological management are to be considered. Influence according to the cause of damage has occurred in secondary(indirect) influence or simultaneous occurrence of several damage types. Considering all these aspects, when type of the damage is complex, restoration process for each of former mentioned 6 damage types with solitary influence should be considered in unison.

• Archives of Pharmacal Research
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• 제25권5호
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• pp.664-668
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• 2002

KR-31543,(2S,3R,4S)-6-amino-4-[N-(4-chlorophenyl)-N-(2-methyl-2H-tetrazol-5-ylmethyl)amino]-3,4-dihydro-2-dimethoxymethyl-3-hydroxy-2-methyl-2H-1-benzopyran is a new neuroprotetive agent for ischemia-reperfusion damage. The in vitro and in vivo metabolism of KR-31543 in rats has been studied by LC-electrospray mass spectrometry. Rat liver microsomal incubation of KR-31543 in the presence of NADPH resulted in the formation of a metabolite M1. M1 was identified as N-(4-chlorophenyl)-N-(2-methyl-2H-tetrazol-5-ylmethyl)amine on the basis of LC-MS/MS analysis with the synthesized authentic standard. Rat CYP3A1 and 3A2 are the major CYP isozymes involved in the formation of M1.

• Current Photovoltaic Research
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• 제3권4호
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• pp.112-115
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• 2015

In this study, the surface of ITO films was modified using $N_2-O_2$ molecular plasma, and the effects of oxygen concentration in the plasma on the ITO surface properties were investigated. Upon plasma treatment of ITO films, the surface roughness of ITO films seldom changed up to the oxygen concentration in the range of 0% to 40%, while the roughness of the films slightly changed at or above the oxygen concentration of 60%. The contact angle of water droplet on ITO films dramatically changed with varying oxygen concentration in the plasma, and the minimum value was found to be at the oxygen concentration of 20%. The plasma resistance at this condition exhibited a maximum value, and the change of resistance showed an inverse relationship compared to that of contact angle. From these results, it was conjectured that the chemical reactions in the sheath of the molecular plasma dominated more than the physical actions due to energetic ion bombardment, and also the plasma resistance could be used as an indirect indicator to qualitatively diagnosis the state of plasma during the plasma treatment.

• Journal of Microbiology and Biotechnology
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• 제12권4호
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• pp.598-602
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• 2002

Damage to cells exposed to radiation is primarily attributed to direct effects on the structure of cellular DNA. Radiation-induced damage of pBluescript SK plasmid DNA and Escherichia coli $DH5\alpha$ were examined in the presence of various branched oligosaccharides, polysaccharides, and/or 8-MOP (8-methoxypsoralen). Branched oligosaccharides efficiently protected DNA and cells exposed to ultrasoft X-ray and UV irradiation. In the presence of 0.2% (w/v) branched oligosaccharides and polysaccharides, DNA can be protected from damage due to W and ultrasoft X-ray by a factor of 1.3-2.1 fo1d and 3.2-8.3 fold, respectively. The protective effect of cells exposed to UV or ultrasoft X-ray was also observed by branched oligosaccharides. The combination of MOP, a photoreagent, with carbohydrates increased the protective effects for DNA and cells, compared with that of a single use of MOP or carbohydrate alone.

• 한국환경농학회지
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• 제33권4호
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• pp.231-238
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• 2014

BACKGROUND: Biochar (BC) has a great potential for enhancing soil fertility and carbon sequestration while facilitating beneficial waste disposition. Therefore, it is essential to assess and mitigate any inadvertent consequences associated with soil biochar amendment. Earthworm activity is very vital in the soil system, yet there are a limited number of studies that have examined their impact resulting from biochar application to soil. METHODS AND RESULTS: In this study, the survival, growth, reproductive tests, and oxidative DNA damage tests (measured by 8-hydroxydeoxyguanosine (8-OHdG) and catalase (CAT) activities) to assess the potential toxicity to earthworm Eisenia fetida in artificial soil amended with BCs were investigated. The BCs derived from perilla meal, sesame meal, and pumpkin seed were pyrolyzed at 300 and $550^{\circ}C$, and then amended with soil at a rate of 5%. All the earthworms survived, but lost weight compared to control soil after 28 day incubation period. Moreover, the BC-amended soils did not significantly affect the cocoon numbers of earthworms. Slightly higher concentrations of 8-OHdG and CAT were observed in earthworms present in BC-treated soil than those in control soil. Furthermore, the 8-OHdG concentrations in the soil amended with BC produced at $550^{\circ}C$ were greater than those at $300^{\circ}C$, and it slightly decreased as the incubation time increased. CONCLUSION: These observations could be due to higher contents of toxic metal(loid)s and also higher pH in BCs pyrolyzed at $550^{\circ}C$ than $300^{\circ}C$. While BC is efficiently being used in agricultural fields, this study suggests that it is required to assess the unintended negative impacts of BC on soil ecosystems.

• 한국산학기술학회논문지
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• 제21권3호
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• pp.488-496
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• 2020

본 연구는 국내·외에서 질산화학사고를 바탕으로 사업장, 실험실, 병원, 용기파손, 화학물질 오 주입으로 이상반응으로 인한 유독가스가 발생하고, 여러 사례들을 바탕으로 질산의 위험성과 화학사고 발생 시 발생할 수 있는 상황과 안전성에 대한 사례검토를 통해서 5년간의(2014년부터 2018년까지) 질산 화학사고 사례 대상으로 각 연도별, 사고현황, 사고유형, 사고원인, 사고 장소 등의 사례를 분석하여 안전교육과 질산화학사고 발생 시 개선 방안을 검토하였다. 그 결과 36건의 질산 화학사고가 조사되었으며, 그중 16건의 작업자 부주의사고가 발생하였고, 8건의 운송사고와 12건의 시설괸리 부족과 같은 사고가 발생하였다. 질산화학사고는 지속적으로 발생하고 있으며, 이를 바탕으로 CARIS를 활용한 독성영향범위를 최악에 시나리오를 산정하여, 피해영향범위를 통해서 효과적인 사고대응 범위를 측정하였고, 질산화학사고 초기대응방법과 사고예방을 위해서 안전교육 강화와 비상조치계획과 상관관계식을 바탕으로 영향범위를 예측하여, 정량화된 자료를 파악하였다. 또한 주민대피 선정이 수월하게 할 수 있는 상관관계식을 바탕으로 영향범위의 신뢰성을 검토하고, 실제 사업장 사고 시나리오에 적용하여 사고 시 비상상황에 사고대응 효과와 예방대책을 제시하였다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 춘계 학술발표회 논문집
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• pp.561-568
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• 2005

The factors affecting the long-term design strength of geogrid can be classified into factors on creep deformation, installation damage, temperature, chemical degradation and biological degradation. Especially, creep deformation and installation damage are considered as main factors to determine the long-term design strength of geogrid. Current practice in the design of reinforced soil is to calculate the long-term design strength of a reinforcement damaged during installation by multiplying the two partial safety factors, $RF_{ID} and RF_{CR}$. This method assumes that there is no synergy effect between installation damage and creep deformation of geogrids. Therefore, this paper describes the results of a series of experimental study, which are carried out to assess the combined effect of installation damage and creep deformation for the long-term design strength of geogrid reinforcement. The results of this study show that the tensile strength reduction factors, RF, considering combined effect between installation damage and creep deformation is less than that calculated by the current design method.

• 한국산학기술학회논문지
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• 제21권10호
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• pp.308-316
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• 2020

본 연구에서는 암모니아 누출사고 발생 시 지방자치단체에서 신속하게 주민대피 및 알림을 결정할 수 있도록 화학물질사고대응정보시스템(CARIS)을 활용한 피해영향거리 산정식을 도출하고자 하였다. 암모니아는 화학물질관리법상 사고대비물질이자 화학물질안전원에서 정한 주민대피 대비물질 16종 중 하나이며, 2014년부터 2019년 기간 동안 화학사고가 58건으로 가장 빈번하게 발생한 화학물질이다. 연구에서는 미국환경보호국(EPA)에서 지정하고, 유아 및 어린이, 노인 등의 취약집단을 포함하며 일반 인구에 적용 가능한 급성노출기준인 AEGL을 기준으로 암모니아의 노출시간에 따른 피해영향거리 산정식을 도출하였다. AEGL-3 농도기준에 따른 위험지역 구분과 AEGL-2 농도기준에 따른 준위험지역을 구분을 할 수 있는 농도별, 노출시간별 산정식을 도출하였으며, 도출된 산정식으로 얻어진 피해영향거리 수치와 화학물질사고대응정보시스템의 피해영향거리 수치간의 상대표준편차를 비교한 결과 0~2 % 범위인 것으로 조사되었다. 따라서 지방자치단체에서는 실제 사고 현장 상황을 고려하고 연구에서 도출된 적합한 피해영향거리 산정식을 적용하여 사고 원점 인근의 주민을 소산하거나 실내대피 알림 등의 보호조치에 활용될 수 있도록 하여야 한다.

• 한국자원식물학회지
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• 제23권2호
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• pp.172-178
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• 2010

천연집단에 서식하는 개비자나무 개체들을 이용해 무생물 및 생물적 환경인자가homoharringtonine(HHT) 함량에 미치는 영향을 조사하여 향후 항암제 가능성이 있는 HHT의 고부가가치 산업적인 생산이 기대되는 연구에 기초자료를 제공하고자 본 연구를 수행하였다. 무생물적 환경인자(토양습도, 토양pH, 서식밀도, 기온)와 HHT 함량과의 상관관계에 있어 HHT 는 토양습도(0.77)와 토양pH(-0.68)에서 높은 상관을 보였다. 고도에 따른 무생물적 환경인자 (토양습도, 토양pH)와 HHT 의 함량 관계에 관해 다중회귀 분석을 실시한 결과, 토양 습도의 회귀계수($26.48^{***}$) 만 유의하여 토양 습도가 상대적으로 HHT 함량에 높은 영향을 미치는 것으로 나타났다. 생물적 환경인자(damage index)에 따른 HHT 함량에 미치는 영향을 살펴 본 결과, HHT는 2차곡선회귀적으로 증가하다 감소하는($H=278.23+1242D-398.87D^2$) 경향을 보였고 damage index는 HHT 함량에 높은 영향을 미치는 것으로 분석되었다. 마지막으로 HHT 의 함량에 영향을 미치는 최적환경인자를 분석한 결과, damage index와 토양 습도 모두가 2차다항회귀식으로 가장 적합하였고 결정계수는 각각 0.73와 0.67로 damage index가 상대적으로 HHT 함량에 높은 영향을 미치는 것으로 나타났다. 이는 섭식자 또는 균류와 같은 스트레스로 인한 방어기작이 HHT 의 생성에 높은 영향을 미치는 것으로 판단된다.