• Journal of Adhesion and Interface
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• v.8 no.4
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• pp.14-22
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• 2007

In the present study, the effect of milled glass powder and liquid-type nitrile rubber (NBR) on the thermal stability of phenolic resin and the dynamic mechanical properties of glass braid/phenolic composites has been investigated by means of thermogravimetric analysis and dynamical mechanical analysis. It was found that both milled glass power and NBR filled in the waterborne phenolic resin significantly influenced the thermal stability of phenolic resins and the storage modulus and tan delta of the composites. The presence of glass powder increased the thermal stability of the phenolic resin, whereas the presence of NBR resulted in the weight loss in the specific temperature range. The thermal stability of the phenolic resins without and with the fillers was dependent not only on the cure temperature but also on the cure time. The variation of the storage modulus and tan ${\delta}$ of strip-type glass braid/phenolic composites was also influenced with the introduction of glass powder and NBR to the phenolic matrix as well as by the cure conditions given.

• Journal of Soil and Groundwater Environment
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• v.10 no.5
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• pp.45-51
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• 2005

The sorption/desorption characteristics of phenanthrene on the natural manganese oxide (NMD) were investigated in the presence of phenolic compounds. 4-chlorophenol (4-CP) was effectively oxidized by NMD catalyzed reaction and transformed into humic-like macromolecular compound through inter-or cross-coupling reaction between byproducts. As 4-CP was degraded with time, sorbed amount of phenanthrene on NMD was significantly increased, resulting from the formation of oxidative coupling products. These results imply that NMD can be used for simultaneous treatment of phenolic contaminants and polycyclic aromatic hydrocarbons (PAHs) in soils, sediments, or water. Also, sorbed phenanthrene on NMD in the presence of 4-CP showed high degree of desorption resistance, indicating that sequestration process of phenanthrene was ongoing with time.

• Journal of the Korean Society of Hazard Mitigation
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• v.4 no.2 s.13
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• pp.29-34
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• 2004

The time to ignition, heat release rate characteristics, and carbon monoxide yield of fiber reinforced and sandwich phenol resin were investigated with cone calorimeter. The fire characteristics of unsaturated polyester, mostly being applied to the existing passenger train, and phenolic resin were compared. DSC & TGA was used to monitor the degree of thermal decomposition and weight loss for the phenolic resin. According to the cone calorimeter data, the time to ignition was shorter, heat release rate, and CO yield was higher as the external heat flux increased. Under the same heat flux, the time to ignition of sandwich type phenolic resin was shorter than that of laminated. The result of comparison between unsaturated polyester and phenolic resin was that phenolic resin was shown to have better fire resistance than unsaturated polyester.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.6
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• pp.713-720
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• 2006

This study was designed to investigate the possible utilization of Ligustrum japonicum leaves as a source of functional ingredients. Contents of total phenolic compounds and condensed tannin were $0.89{\sim}1.53%$ and $0.10{\sim}0.13%$, respectively. The major flavonoid compounds in the leaves of L. japonicum were luteolin, apigenin and their glycosides. Tyrosol, t-cinnamic acid, p-hydroxybenzoic acid, vanillic acid, shikimic acid and protocatecuic acid were detected in free phenolic acid, while tyrosol, t-cinnamic acid, ferulic acid, esculetin, caffeic acid, p-coumaric acid and hydroxytyrosol were detected in esterified phenolic acid. The insoluble phenolic acid contained tyrosol, t-cinnamic and p-caoumaric acid.

• Applied Chemistry for Engineering
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• v.17 no.1
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• pp.100-105
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• 2006

The photocatalytic activity of phenol degradation was investigated with the variation of operating parameters in $UV/TiO_2$ honeycomb reactor. In the comparison of phenol degradation rates among various $TiO_2$, Ishihara (STS-02)-coated honeycomb exhibited a slightly higher photocatalytic activity than Degussa P25-coated honeycomb. On the other hand, honeycomb coated by alcohol-mixed $TiO_2$ (N Co.) did not exhibit any photocatalytic activity on phenol degradation. With the increase of Degussa P25 coating amounts, the honeycomb reactor exhibited the gradual increase of phenol degradation rates. The degradation rate of phenol over $UV/TiO_2$ (Degussa P25) honeycomb reactor was asymptotically increased up to 500 mL/min, subsequently followed by a slight decrease as the recirculation rate (100~700 mL/min) was increased. UV absorption at 269 nm was high due to partial degradation of phenol at initial reaction time because the honeycomb surface was pre-adsorbed by phenol prior to UV irradiation.

• Applied Chemistry for Engineering
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• v.9 no.2
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• pp.238-242
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• 1998

Wood powder filled phenolic resin composites of different composition were prepared and their mechanical properties were investigated for optimum conditions. The composites showed maximum mechanical strength when the phenolic resin content was 45 wt%. Polyurethane prepolymer(PU) was evaluated as a modifier of the phenolic resin composites. Blocking of the isocyanates in the PU with phenol was necessary for homogeneous mixing of raw materials for the components. Maximum mechanical strength of the PU modified composites was observed when the PU content was 5 wt%. It was found that the mechanical strength of the composites cured at $210^{\circ}C$ were higher than those of the composites cured at $150^{\circ}C$.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.11
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• pp.1985-1994
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• 2000

This research was designed to investigate the effect of initial adsorbed amount of phenol, temperature, and pH on the desorption reaction of phenol from spent activated carbon loaded with phenol. Methanol, acetone, and N,N-dimethylformamide( DMF) were used as test organic solvents. The initial adsorbed quantities of phenol investigated here were 166.1mg/g, 180.7mg/g, and 197.9mg/g. The effect of temperature was evaluated from 15 to $55^{\circ}C$ with an interval of $10^{\circ}C$, while that of pH was investigated under acidic. neutral. and alkaline conditions. The extent of phenol desorption was proportional to the strength of dipole moment such as methanol < acetone < DMF. Over 90% desorption of phenol was achieved by acetone and DMF. The quantity of des orbed phenol by the organic solvents decreases with increasing the initial adsorbed amount of phenol. DMF is affected least by the initially adsorbed amount of phenol. An increase in reaction temperature leads to higher desorption of phenol. Desorption reaction by methanol is most sensitive to the temperature. As the pH of solvents increases. the desorption rate is also increasing. At pH=12. the desorption rate of phenol by methanol increases sharply by 10%. Although methanol demonstrated the weakest desorption power. the desorption capacity of methanol would approach that of acetone and DMF by adjusting temperature and pH. Methanol may emerge as a promising solvent for removing phenol from activated carbon because of acceptable regeneration efficiency as well as relatively cheap price.

• KSBB Journal
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• v.11 no.6
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• pp.681-688
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• 1996

In the removal of phenolic precipitates formed by horseradish peroxidase (HRP) and $H_2O_2$ from waste water, the effects of the concentrations of phenolic compounds and $H_2O_2$ on the removal efficiency of various phenols were studied. More than 90% of various phenolic compounds were removed from the aqueous solutions (pH 5-7) by HRP and H2O2. The removal efficiency of phenolic compounds by HRP was reduced to a great extent when the initial concentration of $H_2O_2$ was over 10mM. Furthermore, no phenolic compounds were removed when 50mM of $H_2O_2$ was used. The HRP's turnover number, which indicates the number of phenolic molecules removed per one molecule of HRP, was the largest as 18047 for p-ethoxyphenol while it was the smallest as 1244 for m-chlorophenol when the initial concentrations of phenolic compounds and H2O2 were the same at 1mM. HRP which was separated from the aqueous solution containing phenol and $H_2O_2$ after 24hr of reaction revealed structural changes and diminished activity. The Soret absorbance near 404nm of this HRP sample was decreased to 48% of that of fresh HRP. The values of kcat and kcat/Km of this HRP sample for the oxidation of guaiacol were also reduced to 41% and 51% of those of fresh HRP, respectively. The removals of nonphenolic aromatic compounds such as benzene, ethylbenzene, and toluene (BET) by HRP and $H_2O_2$ were enhanced when phenols were coexisting in the aqueous solutions of BET.

• Magazine of the Korean Society of Agricultural Engineers
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• v.37 no.2
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• pp.41-52
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• 1995

혼합상태에서 유기화합물들이 토양에 흡착하는 성질에 관해서 5개의 유기화합물(페놀,2,4-디크로로페놀, 2,4,6-트리크로로페놀, 부루신, 따이오유리아)과 2종류의 토양을 이용하여 연구하였다. 일반적으로 따이오유리아를 제외하고는 한가지 물질이 혼합상태에 있는 다른물질이에 의 흡착력이에 제약을 받아서 단독으로 있을때 보다 흡착율이 낮았다. 따이오유리아는 단독인 경우보다 혼합상태일 때 더 많은 흡착을 보였는데 이는 혼합상태에서 오히려 흡착이 증가할수도 있음을 나타낸다. 혼합이 흡착에 비치는 영향은 페놀의 혼합상태와 단독상태에서의 흡착상태를 여러가지 형태로 비교하여 검토하였는데 산성이고 유기물질이 많은 토양보다 혼합으로 인한 흡착의 억제 효과가 뚜렷하였다.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2001.05a
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• pp.164-165
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• 2001

본 연구는 방향족 화합물질 중 페놀폐수에 대한 생물학적 처리를 위해 본 실험실에서 분리한 페놀분해능이 우수한 Rhodococcus sp. EL-GT의 catechol 분해시 1,2-dioxygenase 분해활성이 높은 것으로 보아 분해경로가 ortho-pathway임을 알 수 있었다. 향후 Rhodococcus sp. EL-GT의 페놀분해 균의 유전학적 연구를 통하여 방향족 화합물의 분해에 보다 우수한 균으로 개발시켜 효율적인 처리에 이용가능성을 예측할 수 있었다.