• Journal of the Korean earth science society
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• v.31 no.6
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• pp.573-583
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• 2010

A paleobotanical study of the fossil woods has been carried out from the Tertiary Janggi Group, Pohang Basin. Three species belonging to three genera of Ulmus sp., Prunus sp., and Acer sp. were identified from the Lower Coalbearing Formation, and two species of two genera of Taxodioxylon sp. and Fagus hondoensis (Watari) from the Upper Coal-bearing Formation. As our specimens are mostly poorly preserved, it is difficult to give clear specific names, but mostly are all characteristic constitutional elements of the Miocene fossil woods in Korea. The values of mean sensitivity measured from the fossil woods of Lower and Upper Coal-bearing Formations are 0.367 and 0.370 respectively, but they are more than 0.30. Based on the present two data mentioned above, it stands to reason that there were many changes in the water supply to the roots of the woods or having influence to some degree each year because of the seasonal changes in rainfall.

• 한국지구과학회:학술대회논문집
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• 2001.09a
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• pp.37-37
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• 2001

• Journal of the Korean earth science society
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• v.36 no.1
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• pp.51-58
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• 2015

In order to understand the broad outline and palaeobotanical significances, the fossil woods from the Korean Peninsula were integrated through the literature surveys. Types and diversity of them are gradually increasing from Mesozoic to Cenozoic, especially increased sharply in Cenozoic. During the Early Mesozoic, six conifer taxa belonging to four genera were described, which corresponds to about 6% of the Daedong flora. Those of the Late Mesozoic are all conifers, consisting of fifteen taxa belonging to seven genera, which corresponds to about 29% of the Nakdong flora. During the Neogene, thirty four taxa belong to sixteen families were described. Those woods mostly consist of dicotyledon and have the greatest diversity compared to other geologic eras, which corresponds to about 83% of the Janggi flora. It is inferred that such a rapid increase of the silicified wood fossils in Neogene are due to the abundant presence of dicotyledon in floral composition and of pyroclastic rocks in strata, which are appropriate for preserving wood as fossils.

• Journal of Conservation Science
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• v.1 no.1 s.1
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• pp.12-26
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• 1992

Ilsan peat-bed site, newly constructed city area, is located at the northern part of Seoul. This site is situated near the mouth of Han river, which flows through central Korea. Many fossil woods were excavated from this site, and surveyed the wood anatomical features. Totally 90 specimens were identified into 10 species including two roots and five barks which were not identified in detail. Alnus japonica and A. maxmowiczii are the most common and occupied 26. 7%, 34.4% of the total specimen number respectively, and then other species which excavated from Ilsan area are follows : Fraxinus rhynchophylla(18.9%), Lepido-balanus spp.(3.3%), Maackia amurensis(2.2%), Diospyros spp.(2.2%), Juglans mandshrica(1.1%), Prunophora spp.(1.1%), Malus or Pyrus spp.(1.1%), Rhamnus spp.(1.1%). Among the identified species there are fairly some species growing in the central - or northern temperate zone, such as A. maxmowiczii, F. rhynchophylla, Lepidobalanus spp., M. amurnsis, J. mandshurica, Rhumnus spp. Therefore, it can be estimated that the former temperature of Ilsan area was same or slightly cold than today. The species bearing fruit for food as .J, mandshunca, Diospyros spp., Prunophora spp., Mulus or Pyrus spp. were regarded as artificially planting trees, because they do not grow together in the same site.

• Environmental Mutagens and Carcinogens
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• v.23 no.1
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• pp.35-40
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• 2003

Polycyclic aromatic hydrocarbons (PAH) are frequently detected in food, water, soil, and sediment and are widespread environmental pollutants formed by the incomplete combustion of fossil fuels, woods and other organic matter. PAHs are considered to be probable human carcinogens. The mechanism of action of PAHs has been studied extensively, however it is not clear how PAHs turn on CYP1A1 in human breast cancer. Our laboratory have been studied the effect of PAHs in the human breast cancer cell MCF7. In this study, we examined the ZR-75-1 human breast cancer cells as a new system to evaluate bioactivity of PAHs. ZR-75-1 human breast cancer cell line responses to estrogen and progesteron. We have been able to estbilish long term culture system of this cells then used for the study to observe the effect of PAHs. We demonstrate that PAHs induced the CYP1A1 promoter and 7-ethoxyresolufin O-deethylase (EROD) activity in a concentration-dependant manner. RT-PCR analysis indicated that PAHs significantly up-regulate the level of CYP1A1 mRNA. Some of PAHs showed stronger stimulatory effect on CYP1 gene expression than TCDD. Apparently, ZR-75-1 cells have Aryl hydrocarbon receptors, therefore it would be good experimental tool to study the cross-talk between PAHs and steroid actions.

• Environmental Engineering Research
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• v.24 no.1
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• pp.117-126
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• 2019

Activated carbon is carbon produced from carbonaceous source materials, such as coconut shells, coals, and woods. In this study, an activated carbon production system was analyzed by carbonization and activation in terms of environmental impact and human health. The feedstock of wood wastes for the system reduced fossil fuel consumption and disposal costs. Life cycle assessment methodology was used to analyze the environmental impacts of the system, and the functional unit was one tonne of wood wastes. The boundary expansion method was applied to analyze the wood waste recycling process for activated carbon production. An environmental credit was quantified by avoided impact analysis. Specifically, greenhouse gases discharged from 1 kg of activated carbon production system by feeding wood wastes were evaluated. We found that this system reduced global warming potential of approximately $9.69E+00kg\;CO_2-eq$. compared to the process using coals. The environmental benefits for activated carbon production from wood wastes were analyzed in contrast to other disposal methods. The results showed that the activated carbon system using one tonne of wood wastes has an environmental benefit of $163kg\;CO_2-eq$. for reducing global warming potential in comparison with the same amount of wood wastes disposal by landfilling.