• Journal of the Korean Society of Tobacco Science
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• v.12 no.2
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• pp.67-75
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• 1990

The pyrolytlc behavior of cocoa powder, a flavorant of tobacco smoking products, was examined by determining its pyrolyzate constituents. Cocoa powder was pyrolyzed of two cigarette smoking conditions'distillation-pyrolysis zone(35$0^{\circ}C$, 55$0^{\circ}C$) and high temperature zone($650^{\circ}C$, 85$0^{\circ}C$). Pyrolyzate was flushed from the tube by NB gas into CS2 trap in dry ice-acetone cooled bath and charcoal tube and its constituents were analyzed by GC/MS. As results, the major components of pyrolyzates were identified as hydrocarbon and phenolic compounds. In addition to these, aldehyde, ketone, pyrazin in very small amount. Component changes were observed with temperature increase; decane, styrene, tridecane, m-cresol,4-ethylphenol were increased while hexadecane, tetradecane were decreased. o-cresol and 2-ethylphenol were constant in amounts despite temperature change.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.83-84
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• 2002

For estimation of chain-matching phenomena between normal paraffin as a solvent and straight-chain fatty acid as an additive, the density measurement of n-dodecane, n-tetradecane and n-hexadecane were carried out at oil temperature 313K and pressure up to 1.3 GPa. Their solidification pressure were easily determined by the appearance of molecular crystal, abrupt volumetric contraction and generation of heat of solidification and showed minima under the matching condition. The bulk modulus K of molecular crystal was evaluated using phase diagram. The bulk modulus showed maxima under the each matching condition. The chain matching effect on the bulk modulus beyond the scope of the interfacial phenomena are confirmed.

• Archives of Pharmacal Research
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• v.27 no.10
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• pp.1020-1022
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• 2004

A new ceramide alomacrorrhiza A was isolated from the ethanolic extract of the plant Alocasia macrorrhiza (L.) Schott. Its chemical structure was elucidated as (2S,3S,4R)-2N-[(2'R)-2'- hydroxy-hexacosanoyl]-tetradecane-1,3,4-triol based on extensive 1D, 2D NMR, EI-MS, FABMS, HR-FAB-MS spectroscopic data and chemical degradation studies.

• YAKHAK HOEJI
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• v.28 no.1
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• pp.11-16
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• 1984

As main index of petroleum pollution in the marine organisms n-, iso-paraffins were purified with clean-up method and measured by FID-GC. Ten species of fishes from the near seas of Korea were employed for the study. n-Heptadecane was detected in most fishes. n-Hexadecane and n-octadecane of n-paraffins were highly accumulated in four species of fishes(Seriola quinqueradiata, Sardinia melamosticta, Clupanodon punctatus and Stromateoids argentus), also n-tetradecane and n-hexadecane accumulated in Cololadis saira. Remarkable peak pattern of n-paraffins was not observed in other fishes. Pristane of iso-paraffins was detected in four species of fishes (Sardinia melamosticta, Clupanodon punctatus, Stromateoides orgentus and Cololadis saira).

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.10
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• pp.1271-1277
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• 2008

Competitive displacement of methylcellulose (MC) absorbed at the oil-water interface was investigated by interfacial composition, surface shear viscosity, or surface tension measurements. It was found that all emulsifiers could competitively displace the interfacial MC from the oil-water interface but their behaviors were different from each other. With Tween 20 added to MC emulsion (1 wt% MC, 10 wt% n-tetradecane, 20 mM bis-tris, pH 7), MC load was steadily decreased with increasing concentrations of the emulsifier, as confirmed by surface shear viscosity measurements; moreover, there was complete MC displacement from the emulsion droplet surface at high concentration (0.1 wt%). The oil-soluble Span 80 was found to show a synergism with MC at the interface, which resulted in higher MC load at relatively low emulsifier concentrations ($\leq$0.05 wt%). At a higher emulsifier concentration (0.1 wt%) limited MC displacement was observed. These results were well supported by surface shear viscosity measurements. With water-soluble SDS, MC load was decreased with increasing concentrations of the emulsifier. Unlike Tween 20, however, it was found that at high concentrations (> 0.1 wt%), there was still some MC remaining at the droplet surface. Surface tension measurements are suggestive of an interfacial complex between MC and SDS.

• Economic and Environmental Geology
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• v.36 no.5
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• pp.349-356
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• 2003

As industrial activities are growing, pollutants found in the contaminated land are getting diverse. Some contaminated areas are subject to mixed wastes containing both organic and inorganic wastes such as hydrocarbon and heavy metals. This study concerns with the influence of the degradation of organic pollutants on the coexisting heavy metals, expecially for As. As mainly exists as two different oxidation state; As(III) and As(V) and the conversion between the two chemical forms may be induced by organic degradation in the soil contaminated by mixed wastes. We operated microcosm in an anaerobic chamber for 60 days, using sandy loam. The soils in the microcosm are artificially contaminated both by tetradecane and As, with different combination of As(III) and As(V); As(III):As(V) 1:1, As(III) only and As(V) only. Although not systematic, ratio of As(III)/As(Total) increase slightly at the later stage of experiment. Considering complicated geochemical reactions involving oxidation/reduction of organic materials, Mn/Fe oxides and As, the findings in the study seem to indicate the degradation of the organics is connected with the As speciation. That is to say, the As(V) can be reduced to As(III) either by direct or indirect influence induced by the organic degradation. Although Fe and Mn are good oxidising agent for the oxidation of As(III) to As(V), organic degradation may have suppressed reductive dissolution of the Fe and Mn oxides, causing the organic pollutants to retard the oxidation of As(III) to As(V) until the organic degradation ceases. The possible influence of organic degradation on the As speciation implies that the As in mixed wastes may be have elevated toxicity and mobility by partial conversion from As(V) to As(III).

• Analytical Science and Technology
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• v.19 no.1
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• pp.86-95
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• 2006

This study was carried out to estimate leaching characteristics of incineration residues from municipal solid waste incinerators, and determine organic compounds in raw ash, leaching water and leaching residue. A total of 44 organic compounds, which were analyzed by GC/MSD and identified by wiley library search, were contained in bottom ashes. A total of 17 organic compounds were contained in fly ashes. Bottom ash and fly ash were found to contain a wide range of organic compounds such as aliphatic compounds and aromatic compounds. Organic compounds such as Ethenylbenzene, Benzaldehyde, 1-Phenyl-Ethanone and 1,4-Benzenedicarboxylic acid dimethyl ester were detected in raw ash, leaching water and residues (from bottom ash). Organic compounds such as Naphthalene, Dodecane, 1,2,3,5-Tetrachlorobenzene, Tetradecane, Hexadecane and Pentachlorobenzene were detected in raw ash, leaching water and residues (from fly ash). Through the leaching characteristics of incineration residue, it was represented that the open dumping of incineration residue can contaminate the soil and undergroundwater. In order to prevent environmental contamination that derived from extremely toxic substances in the incineration residues, it is particularly important that the incineration residues should be treated before disposal the incineration residues. Further study and proper management about leaching characteristics of organic compounds might be required.

• Clean Technology
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• v.29 no.4
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• pp.279-287
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• 2023

Fine dust emitted from coal combustion is classified into filterable particulate matter (FPM) and condensable particulate matter (CPM). CPM is difficult to control with existing air pollution control devices, so research is being conducted to understand the characteristics of CPM. Components constituting condensable particulate matter (CPM) are divided into inorganic and organic components. There are many quantitative analysis results for the ionic components, which account for a significant proportion of the CPM inorganic components, but little is known about the organic components. Thus, there is a need for a quantitative analysis of CPM organic components. In this study, aromatic hydrocarbons (toluene, ethyl benzene, m,p-xylene, and o-xylene) and n-alkanes with 10 to 30 carbon atoms were quantitatively analyzed to understand the organic components of CPM emitted from a lab-scale coal combustor. Of the aromatic hydrocarbons, toluene accounted for 1.03% of the CPM organic components. On the other hand, the contents of ethyl benzene, m,p-xylene, and o-xylene showed low values of 0.11%, 0.18%, and 0.51% on average, respectively. Among the n-alkanes, triacontane (C₃₀) showed a high content of 2.64% and decane (C₁₀) showed a content of 2.05%. The next highest contents were shown with dodecane (C₁₂), tetradecane (C₁₄), and heptacosane (C₂₇), all of which were higher than that of toluene. The n-alkane substances that had detectable concentrations showed higher contents than ethyl benzene, m,p-xylene, and o-xylene except for tetracosane (C₂₄).

• Polymer(Korea)
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• v.39 no.3
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• pp.403-411
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• 2015

A series of hydrophobically associating fluorinated amphiphilic polyacrylamide copolymers with remarkably high heat resistance and salt tolerance were synthesized by free radical micellar copolymerization, using acrylamide (AM) and sodium 2-acrylamido-tetradecane sulfonate ($AMC_{14}S$) as amphiphilic monomers, and 2-(perfluorooctyl) ethyl acrylate (PFHEA) as hydrophobic monomer. The structure of the terpolymer was characterized by FTIR, $^1H$ NMR and $^{19}F$ NMR. The solution properties of the terpolymers were investigated in details, and the results showed that the terpolymer solution had strong intermolecular hydrophobic association as the concentration exceeded the critical association concentration 1.5 g/L. The terpolymer solution possessed high surface activity, viscoelasticity, excellent heat resistance, salt tolerance and shearing resistance. The viscosity retention rate of copolymer solution was as high as 59.9% under the condition of fresh wastewater, $85^{\circ}C$ and a 60-days aging test.

• Journal of Soil and Groundwater Environment
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• v.17 no.2
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• pp.7-14
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• 2012

Batch tests were carried out to evaluate the thermal treatment of low volatile organic compounds in low-permeability soil. The chemical oxidation by sodium persulfate catalyzed by heat and Fe (II) was evaluated. Enhanced persulfate oxidation of n-decane (C-10), n-dodecane (C-12), n-tetradecane (C-14), n-hexadecane (C-16), and phenanthrene was observed with thermal catalyst, indicating increased sulfate radical production. Slight enhancement of the pollutants oxidation was observed when initial sodium persulfate concentration increased from 5 to 50 g/L. However, the removal efficiency greatly decreased as soil/water ratio increased. It indicates that mass transfer of the pollutants as well as the contact between the pollutants and sulfate radical were inhibited in the presence of solids. In addition, more pollutants can be adsorbed on soil particles and soil oxidant demand increased when soil/water ratio becomes higher. The oxidation of the pollutants was significantly improved when catalyzed by Fe(II). The sodium persulfate consumption increased at the same time because the residual Fe(II) acts as the sulfate radical scavenger.