• Polymer(Korea)
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• v.36 no.6
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• pp.768-775
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• 2012

Alginate, obtained from the seaweeds, is a widely used biomaterial for cell transplantation, since its positive effect on viability of capsulized cells and its easier encapsulation capability of living cells. Demineralized bone powder (DBP), derived from the natural bone tissue, is widely applied for clinical trials for its low rate of reaction and antigenicity. A chondrocyte was seeded into an alginate with DBP of different contents, and a microcapsule was produced. The adhesion and proliferation of cells was observed through the MTT analysis, and the PCR was applied to estimate the content of the glycosaminoglycan (sGAG) and collagen, and confirm the specific genetic pattern of the chondrocytes. Also, the alginate microcapsule where the chondrocyte is seeded was extracted after transplantation under the skin of a nude mouse, and was immunochemically stained. The experimental result confirmed that the alginate microcapsule containing 1% of DBP not only showed the highest proliferation of cell but had a positive effect of chondrocytes by the interaction between the alginates and the growth factor in DBP. It can be expected that the microcapsule with application of the alginates and DBP might be an appropriate scaffold for tissue engineering.

• Applied Chemistry for Engineering
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• v.9 no.3
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• pp.330-335
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• 1998

The objectives of this study are summarized with two. The one is to remove of $COD_{Cr}$, color and turbidity with coagulation and ozonation in nonbiodegradable landfill leachate, the other is to compare of water qualities with pre-ozonation and post-ozonation. The results are summarized as follows ; 1) 90 minutes ozonation with $75mgO_3/min$($4.5gO_3/hr$) was conducted at pH 4,7, 10 to remove $COD_{Cr}$. Removal efficiencies were investigated with 48.2%, 52.6%, and 62.3% respectively. As increasing pH, $COD_{Cr}$ removal efficiencies were increased, it was considered that hydroxyl radical($OH{\cdot}$) which strongly oxdize and nonselectively react with organic compounds, was rapidly produced by ozone self-decomposition at high pH. 2) Alum, ferric chloride and ferrous sulfate were used for coagulation as inorganic coagulant. Ferric chloride was investigated with optimal coagulant, and it removed $COD_{Cr}$ about 12.0% at pH5 and dosage of $2,000m{\ell}/{\ell}$. Cation(C-101P), anion(A-601P) and nonion(SC-050) were tested to remove organic pollutants in landfill leachate. Cation(C-101P) was investigated with the most effective organic coagulant, and removal efficiency of $COD_{Cr}$ was 19.8% at pH5 and dosage of $100m{\ell}/{\ell}$. 3) Color and turbidity were removed up to 88.6%, 97.0% at pH10, when contacted 90 minutes with ozone, respectively. These removal efficiencies were much higher than those of $COD_{Cr}$ and $COD_{Mn}$. It was considered that ozone could oxdize the triggering materials of color and turbidity selectively and preferentially. 4) $COD_{Cr}$, color and turbidity were more effectively removed with pre-ozonation than post-ozonation about 8%, 3.5% and 1% respectively. These results were well corresponed with other's studies that pre-ozonation will increase the effect of coagulation.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.7
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• pp.2386-2396
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• 1996

A numerical simulation has been performed for isothermal and reacting flows in an exisymmetric, bluff-body research combustor. The present formulation is based on the density-weighted averaged Navier-Stokes equations together with a k-epsilon. turbulence model and a modified eddy-breakup combustion model. The PISO algorithm is employed for solution of thel Navier-Stokes system. Comparison between measurements and predictions are made for a centerline axial velocities, location of stagnation points, strength of recirculation zone, and temperature profile. Even though the numerical simulation gives acceptable agreement with experimental data in many respects, the present model is defictient in predicting the recoveryt rate of a central near-wake region, the non-isotropic turbulence effects, and variation of turbulent Schmidt number. Several possible explanations for these discrepancies have been discussed.

• Journal of Navigation and Port Research
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• v.40 no.6
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• pp.441-450
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• 2016

A pilot scale biostimulation experiment was performed under field conditions to degrade organic pollutants and PAHs (Polycyclic Aromatic Compounds) in contaminated coastal sediment. During the experiment, the seawater temperature around the sediment varied from $16.5^{\circ}C$ to $21^{\circ}C$, while the sediment pH was stable at 8.4-8.5. The experiment was conducted over a one year period with a control group and a sample group with a applied biostimulant composed of acetate, sulfate, and nitrate. Chemical oxygen demand decreased 39% in the control group and 79% in the sample group. Volatile solids were reduced from 15 to 7 g/kg in the control group and 2.5 g/kg in the sample group. Out of the 2-, 3- ,4- ,5-, and 6-rings of the 16 vital PAHs, the compound including naphthalene (2-ring), took 2 months to degrade completely, while the degradation efficiency was 55.6% in the control group during the same period. In the case of the 3-ring and 4-ring PAHs, complete degradation in the sample and 46% - 100% degradation in control was observed after one year of the experiment. The 5-ring and 6-ring PAHs were degraded to about 77%-100% in the sample group and 26%-87% in the control group during the one year of the experiment. The study results show that biostimulation is a very effective method to improve the degradation rate of organic pollutants and PAHs (Polycyclic Aromatic Compounds) in contaminated coastal sediment.

• Economic and Environmental Geology
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• v.28 no.3
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• pp.259-269
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• 1995

Column leaching tests were conducted using fresh and weathered pulverised fuel ash of some 17 and 40 years old from two major British power plants, with deionised water and simulated synthetic industrial leachate. The former was to see the leaching behaviour of weathered ash and the latter was to see if the formation of secondary products from water and PFA interaction and ameliorating effect in removing metals from industrial leachates. Fresh PFA liberates elevated concentrations of surface-enriched inorganics, including Ca, Na, K, B, $Cr_{total}$, Li Mo, Se and $SO^{2-}_4$. This might indicate their association with the surface of PFA particles. In the column leaching tests using weathered ash and deionised water, elements are not readily leached but are released more slowly, showing relatively constant concentrations. For the case of weathered ash, some readily soluble surface-enriched elements appears to have been liberated in their early stage of leaching and the liberation of glass associated elements are thought to be more important function in controlling the element concentration. The result from column leaching tests exceed for a number of elements when compared with various Water Standards and suggests the leachate from PFA disposal mound needs dilution to achieve target concentrations. PF A shows element retention effect for many elements, including B, Fe, Zn, Hg, Ni, Li and Mo, in the order of fresh Drax ash > weathered Drax ash > Weathered Meaford ash in retaining capacity. Geochemical modelling using a computer program WATEQ4F reveals some solubility controlling secondary solid products. These include $CaSO_4{\cdot}2H_2O$ for Ca, $Al(OH)_3$ for Al and $Fe(OH)_3$ for Fe.

• Korean Journal of Environmental Agriculture
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• v.5 no.2
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• pp.149-155
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• 1986

The fatty acid compositions of phospholipids extracted from leaves and leaf mitochondria, which were sampled from several horicultural plants grown under blue color-deficient sunlight (BCDS), were determined and compared with those from plants grown under natural white colored sunlight(WCS). It was found that the mitochondria isolated from plants grown under BCDS contained phospholipid whose degree of unsaturation in unit of number of double bonds per lipid molecule was remarkably higher than that from plants grown under WCS, the relative increment being $8{\sim}49%$. This was significantly larger than the relative increment, $4{\sim}8%$ for total phospholipid extracted from whole leaves grown under BCDS campared to WCS. This observation demonstrated that the blue light effect of sunlight on the chemical property of cellular membranes, as long as it was concerned with fatty acid composition, arose mainly at the mitochondrial membrane. Also observing that the degree of unsaturation of mitochondrial phospholipid was much lower than that of total phospholipid, it was interpreted that this was the consequence of rather active oxidative destruction of lipid-fatty acid components occuring in mitochondrial membrane by the reactive oxygen species, especially superoxide($O_2-$), which was known to be produced in mitochondrial inner membrane through the side reactions of the respiratory electron transport chain and also probably through the photosensitized reaction involving oxygen induced by blue colored light. Thus, it may be tentatively concluded that the extent of photosensitization in mitochondrial membrane could be considerably reduced under BCDS resulting in lowering of the $O_2-$ level in the respirating organelle The possible involvement of photodynamic action in membrane oxidation was also indicated by the fact that the typical fat-soluble antioxidant, ${\alpha}-tocopherol$, was found to be contained on a higher level in leaves under BCDS than those under WCS.

• The Journal of the Korea Contents Association
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• v.6 no.4
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• pp.146-157
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• 2006

Causal relationship means what relations the result occurred have with a fact as a reason. In general, a formular that no result exists without reasons is used for the method to confirm existence and inexistence of causal relationship. Problematic causal relationships in Private Law are reparations (Article No. 393 of Private Law) due to debt nonfulfillment and reparation due to tort (Application of Article No. 393 by Article No. 750, and No. 763 of Private Law). The purpose pursued by reparation system in private law is to promote equal burden of damages, and the range of reparation at this time is decided by the range of damage and the range of damage is decided by the principle of causal relationship. That the causal relationship theory fairly causes confusion by treating one problem and the other problem as the same thing, instead of dividing them according to the purpose of protection presented by the law is a reason of the criticism from different views.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.9
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• pp.1013-1019
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• 2007

Electronic wastes have increased tremendously. However, any reliable treatment methodologies have rarely been established. Electronic wastes have posed serious disposal problem due to their physico-chemical stability. This paper investigated the application possibility of pyrolysis for the purpose of recycling the p-CCL(phenol based Copper Clad Laminate). Thermogravimetric analysis(TGA) was used to investigate the thermal decomposition pattern of p-CCL. We elucidated the characteristics of pyrolysis by-products at operating temperatures of 280, 350 and $600^{\circ}C$. GC/MS and FT-IR were used to characterize the liquid by-products along with general characterization methods such as Ultimate Analysis, Proximate Analysis and Heating Value, whereas general characterization methods were only introduced for the solid by-products. At a heating rate of $5^{\circ}C$/min, TGA curves exhibited three decomposition stages: (1) low-temperature decomposition region$(<280^{\circ}C)$, (2) medium temperature region$(280\sim350^{\circ}C)$ and (3) high-temperature region$(>350^{\circ}C)$. The major compounds of liquid by-products at low- and medium-temperatures were accounted for by water and phenol, whereas branched phenols and furans were major compounds at high-temperatures. As the temperature increases, volatile quantities decreased but the fixed carbon increased. High heating values of solid by-products($7,400\sim7,600$ kcal/kg) would suggest that the solid by-products could be applicable as fuel. In addition, high fixed carbon but low ash content of the solid by-products offered an implication that they are capable of being upgradable for adsorbent after applying appropriate activating process.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.34 no.4
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• pp.259-268
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• 2008

In this study, the antioxidative effects, inhibitory effects on tyrosinase and elastase and components of Castanea crenata leaf were investigated. The free radical (1,1-diphenyl-2-picrylhydrazyl radical, DPPH) scavenging activity ($FSC_{50}$) of extract / fractions of Castanea crenata left was in the order: 50% ethanol extract ($13.6{\mu}g/mL$) < ethyl acetate fraction (6.2) < aglycone fraction (2.1). Reactive oxygen species (ROS) scavenging activities ($OSC_{50}$ of extract / fractions from Castanea crenata leaf extract / fractions on ROS generated in $Fe^{3+}$-EDTA/$H_2O_2$ system were investigated using the luminol-dependent chemiluminescence assay. The order of ROS scavenging activity was in the order: aglycone fraction (0.8) < 50% ethanol extract (0.5) < ethyl acetate fraction (0.3). The scavenging activity ($IC_{50}$ for ${O_2}^{{\cdot}\;-}$ (superoxide anion radical) generated by NBT method was in the order: ethyl acetate fraction (145.5) < aglycone fraction (65.5). The protective effects on the rose-bengal sensitized photohemolysis of human erythrocytes were investigated. The ethyl acetate fraction exhibited the most prominent cellular protective effect (${\tau}_{50}$, $191.9{\pm}12.2\;min$ at $10{\mu}g/mL$). The inhibitory effect of aglycone fraction ($9.1{\mu}g/mL$) on elastase was higher than oleanolic and ($13.7{\mu}g/mL$). And the inhibitory effect of aglycone fraction ($21.6{\mu}g/mL$) on tyrosinase was higher than arbutin ($226.2{\mu}g/mL$). But 50% ethanol extract rarely exhibited the inhibitory activity on tryosinase and elastase. Flavonoids were contained in Castanea crenata left (96.3 mg / 100 g dried Castanea crenata leaf). And flavonoids contained in ethyl acetate fraction were kaempferol, quercetin, quercitrin, and so on. Quercitrin is the most abundant component. These results indicate that extract / fractions of Castanea crenata can function as antioxidants in biological systems, particularly skin exposed to UV radiation by scavenging free radical and ROS, Castanea crenata leaf extract/ fractions could be used as new cosmeceutical for whitening and anti-wrinkle products.

• Korean Journal of Plant Resources
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• v.23 no.5
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• pp.415-422
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• 2010

Red ginseng(RG, steamed and dried root of Panax ginseng C. A. Meyer, family Araliaceae) and fermented red ginseng(FRG, fermented red ginseng by yeast and lactic acid bacteria) are known to show different pharmacological effects by changed composition of saponins through fermentation. We examined the effects of RG and FRG on $\beta$-hexosaminidase secretion, ICAM-1 expression, the mitogen-induced proliferation of lymphocyte from mice in ex vivo systems and HaCaT cell(keratinocyte) proliferation to compare the anti-allergic and anti-inflammatory effects between both groups. RG groups showed inhibition of $\beta$-hexosaminidase secretion and ICAM-1 expression at $1{\mu}g/ml$, $10{\mu}g/ml$ and the same effects were observed at all concentrations in FRG groups. In our study, RG increased LPS-induced B cell proliferation at $1{\mu}g/ml$ and ConA-induced B cell proliferation at $100\;{\mu}g/ml$ but FRG decreased LPS- and ConA-induced lymphocytes at $100\;{\mu}g/ml$. We showed that FRG increased the proliferation of HaCaT at 1, $10{\mu}g/ml$ but not by RG. These findings suggest that RG and FRG might have anti-inflammatory and anti-allergic effects, which can be needed to proper clinical concentration to applied to various allergic diseases and inflammation.