• Korean Journal of Environmental Agriculture
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• v.19 no.1
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• pp.6-12
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• 2000

This study was carried out to determine the adsorption characteristics of eight pesticides on thirty citrus orchard soil so soil samples were taken from nineteen soil series containing different fractions of organic carbon(Foc). The adsorption characteristics for eight pesticides fitted to Freundlich isotherms. The adsorption isotherms showed C-type for alachlor and chlorpyrifos, L-type for linuron and diniconazole. and S, C, and L-types for metribuzin, metolachlor, and alachlor with increasing Foc, respectively. In particular, the adsorption of chlorothalonil showed S, C, L, and H-types with increasing Foc. Distribution coefficient(Kd) values of metribuzin, metolachlor, and alachlor were below $10\;Lkg^{-1}$ and increased linearly with Foc. Kd values of linuron, diuron and chlorothalonil increased exponentially to 60, 200, and $400\;Lkg^{-1}$, respectively and those of diniconazole and chlorpyrifos increased logarithmically. Kf value. Freundlich adsorption coefficiient, increased with Kd in the same manner with Kd. Furthermore, the linearity of Kf value was larger than that of Kd value.

• Journal of Food Hygiene and Safety
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• v.15 no.3
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• pp.226-234
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• 2000

Protective effect of Corydalis ternata against the carbon tetrachloride-induced toxicity was investigated. Carbon tetrachloride($CCl_4$) induces hepatotoxicity due to the reactive free radical(CCl$_3$ . ) generated by cytochrome P-450 enzyme. We examined effects of hexane, chloroform, butanol and water fractions prepared from the Corydalis ternata methanol extract. Rats were treated with those for 3 days, and liver microsomes and cytosols were prepared at 24 hour after last treatment. Hepatoprotective activity of the water fraction was higher than that of other fractions. To examine mechanism of the hepatoprotective effect of Corydalis ternuta, we measured contents of malondialdehyde(MDA), cytochrome P46O(CYP), glutathione, calcium as well as the activities of NADPH-CYP reductase, glutathione S-transferase(GST), superoxide dismutase(SOD), glutathione peroxidase(GPX) and catalase. The fraction inhibited production of MDA, content of CYP and calcium in liver of water fractions - treated rats as compared with those of CCl4-treated rats. The GST activity was increased. We speculate that the O2 radical scavenging activities of the water fraction might play a key role in the mechanism opposing the progression of $CCl_4$-induced hepatotoxicity, but the activities of SOD, GPX, CAT were decreased. These results suggest that the mechanism might be mainly due to the decrease of CYP contents, act as calcium channel blocker and increase of GST activity rather than $O_2$ radical scavenging activities.

• Journal of Life Science
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• v.16 no.5
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• pp.734-739
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• 2006

This study investigated the hepatoprotective effects of mesangi (Capsosiphon fulvecens) in carbon tetrachloride $(CCI_4)$-induced liver injury. Thirty healthy male Sprague-Dawley rats were divided into three groups : the normal (Normal), $CCI_4$-treated $(CCI_4)$, and mesangi-treated (Exp-CF) groups. Administration of $CCI_4$ increased the levels of GOT, GPT, and LDH in serum, while the levels were significantly decreased by the addition of mesangi. Higher levels of HDL-cholesterol were found in the Normal and Exp-CF groups, which has lower levels of total and LDL-cholesterol. Administration of $CCI_4$ also increased IGFBP-1 expression in serum, but it was decreased in the Exp-CF group. This suggests that $CCI_4$ is involved in the change in IGFBP-1 expression via its hepatotoxicity. The results indicate that mesangi has a hepatoprotective effect in rats given $CCI_4$.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.28 no.4
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• pp.158-177
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• 2023

An estuary is a transitional water area that links the land and sea through rivers and streams, transporting various components from the land to the sea, which plays an important role in determining primary productivity in the coastal environment, and this coastal ecosystem captures a huge amount of carbon into biomass, known as blue carbon, which mitigates climate change as a potential carbon reservoir. This study examined the variation of mean grain size and organic carbon content of the surface sediments for 6 years and analyzed their relationship in the western and southern estuarine areas (Han River Estuary, Geum River Estuary, Yeongsan River Estuary, Seomjin River Estuary, and Nakdong River Estuary) and the East Sea upwelling area. During the sampling period (2015 to 2020), seasonal variation of both properties was not observed, because their variations might be controlled by diverse oceanographic environments and hydrographic conditions within each survey area. However, despite the synoptic problem of all samples, the positive relationship was obtained between the averages of mean grain size and organic carbon content, which clearly distinguishes each survey area. The unique positive relationship in all estuarine areas implies that the same process by sediment clay particles is important in the organic carbon accumulation. However, additional important factor may be expected in the organic carbon accumulation in the East Sea upwelling area. Further necessary data (sedimentation rate, dry bulk density etc) should be required for the estimation of carbon stock to evaluate the major estuaries in Korea as potential carbon reservoirs in the coastal environment.

• Journal of Conservation Science
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• v.20
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• pp.55-65
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• 2007

Black surface layers collected from stone pagodas were analyzed to study the effects of carbon compounds on the blackening of stone surface layer. The total amounts of carbon was measured through elemental analyser. Organic and elemental carbon were measured by combustion ihrornatographic $CO_2$ determination after elimination of carbonates carbon with acid treatment. The elemental carbon concentration in the black surface layer measured 0.52wt.%. This value is not sufficient to explain the complete blackening of stone surface. To trace the origin of carbon in black surface layer on the stone pagoda, aerosol samples for PM 10 were collected at the near sites of the pagoda. The major components of them were soluble ions(42.8wt.%), carbon(38.4 wt.%) and crustal matter(16wt.%). From the high content(13wt.%) of elemental carbon in aerosol ran be deduced that it may be a prime origin for the elemental carbon in the black surface layer on the stone pagoda. The crustal matter in aerosol can be also a origin of silicate mineral in black surface layer and plays a important role in the darkening of black surface layer.

• Journal of the Korean Vacuum Society
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• v.18 no.1
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• pp.49-53
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• 2009

The chemical properties of SiOC film was studied for inter-layer insulator. SiOC film was formed with non polarity due to the appropriate union by the alkyl and hydroxyl group. An amorphous structure of non polarity can induce the low dielectric constant materials. The chemical properties of thin film can define the bonding structure owing to the ionic variation, and the analysis of chemical properties was researched by the carbon content using the FTIR spectra, and induced the film with non polarity. The electrical properties is the electron flow, and is always not the same as the chemical properties. The electrical properties of SiOC film with various flow rate ratios was analyzed and researched the correlation between the chemical properties. SiOC film showed the increasing of the leakage current after annealing process, and abruptly increased the carbon content at some samples. But the sample with increasing the carbon content decreased the leakage current. It means that the chemical properties is not the same as the electrical properties, and the carbon is related with the variation of the bonding structure, and does not contribute the current flow.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.9
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• pp.2065-2070
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• 2010

The diluted PMMA treated $SiO_2$ films as an passivation materials for semiconductor devices was researched by using the FTIR spectra. The diluted PMMA solution with various ratios changed the surface of $SiO_2$ film as the hydrophilic, hydrophobic or hybrid type properties. The sample 7 with little carbon content showed dramatically the chemical variation by the FTIR spectra analysis. Beacuse the little carbon with electrons decreased the polarity and surface energy on the $SiO_2$ film, and then became a stable bonding structure and decreased the leakage current. The FTIR spectra can define the detail variation due to the chemical reaction on the organic thin film, and help to research the characteristic of the organic materials.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.03a
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• pp.42-42
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• 2003

Ni/Si 기판상에 CH$_4$, H$_2$, $N_2$의 혼합기체를 사용하여 $700^{\circ}C$에서 5분 동안 MPECVD법으로 탄소나노튜브 성장시켰다. 이 과정에서 CH$_4$, H$_2$에 대한 $N_2$의 유량비를 여러 가지 값으로 변화시켜 그 성장 양상을 살펴보았다. 혼합기체 내 질소의 함량에 따라 나노튜브의 성장길이와 quality가 달라짐을 SEM과 Raman spectroscopy 측정을 통하여 확인하였다. 나노튜브의 성장 시 혼합기체 내 주입하는 질소량에 의해 나노튜브의 성장길이가 변화됨을 SEM을 통해 관찰할 수 있었고 혼합기체 내 질소의 비율이 커질수록 carbonaceous particle 등의 감소로 인한 나노 튜브의 quality가 향상됨을 Raman spectra를 통해 확인할 수 있었다. 또한 TEM과 SEM 관찰을 통해 성장된 탄소나노튜브가 대나무(bamboo) 구조를 가진 수직 배향된 다중벽 탄소나노튜브임을 확인하였다.

• Resources Recycling
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• v.8 no.3
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• pp.43-48
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• 1999

The pupose of h s study was to develop a process for removal of unburnzd carbon li-om fly ash by froth flotation. "Carbon zero (C.Z)" develqcd by KIGAM, gave the best results, praduci112 cleaned fly ash containing abom 0.1% FC with 72% yieldBased on the results of batch flotation tests, the pilot-scale tests wcre conducted. The result showed that cleaned fly ash with 0.1% FC could be recovered by about 73% yield.t 73% yield.

• Resources Recycling
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• v.8 no.4
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• pp.11-19
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• 1999

Fly ash generated from (he pulverized coal power plant have caused the serious ocean pollution due to the disposal in the ash pond, the life reduction of a power plant and the waste of re-utilizable resource The research to reuse the unburned carbon and mineral composing of the ash has been progressed. In this study. the physical and chemical characteristics of high grade ash and unburned carbon particles obtained from countercurrent column flotation are investigated. The cleaned ash of the less 0,5% loss on Ignition(LOI) in carbon content is a spherical sphere and 39.8${\mu}m$ in size of MMD(Mass Median Diameter). 2.22 $m^2/g$ of specific area. The morphology of high LOI carbon particles is a amorphousness, 76.6 ${\mu}m$ of particle size and 15.2 $m^2/g$ of specific The high grade cleaned ash and the high LOI ash have some difference in the light of physical. chemical and morphological characteristics