HOMO(the highest occupied molecular orbital) and LUMO(the lowest unoccupied molecular orbital) of four recalcitrant polycyclic aromatic hydrocarbons (PAHs) were calculated by MOPAC program(CaChe Co). The previous papers which reported experimental results about radical reaction of PAHs were reviewed. The reported radical reaction positions of four PAHs corresponded with predicted positions in which δE(HOMO-LUMO) was high. From these results, it appears that determining the δE(HOMO-LUMO) of a PAH is a promising method for predicting the radical reaction position.
Esterification reaction between succinic acid and 1,4-butanediol was kinetically investigated in the presence of nontoxic organometallic compound catalyst(ESCAT-100E) at 150-190℃. The reaction rates measured by the amount of distilled water from the reaction vessel. The Esterification reaction was carried out under the first order conditions respect to the concentration of reactants, respectively. The overall reaction order was 2nd. The linear relationship was shown between apparent reaction rate constant and reciprocal absolute temperature. By the Arrhenius plot the activation energy have been calculated as 376.13 kJ/mol under nontoxic organometallic compound catalyst and also apparent reaction rate constant, k' was found to obey first kinetics with respect to the concentration of catalyst.
In this study, the anti-oxidative effects and components of sprout serum were investigated. In the buds, high levels of zinc, iron and manganese were analyzed in addition to copper, magnesium, and potassium. The free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activity of sprout serum was evaluated with IC50. IC50 of sprout serum was 58.0 mgmL-1, and that of vitamin C was 3.7 mgmL-1. In the test of superoxide scavenging activity of sprout serum, the activity was dependent on the concentration of serum. In this case, the IC50 was 2.0 wt%. Cell viability was detected by using the MTT method. Cultured human fibroblast was treated with 15 mM H2O2 and cell viability was 70% in case of control. However, the effect of treating 0.5% of sprout serum was similar to that of 0.0001% of vitamin C.
Melanoma is the most aggressive form of skin cancer and is the fastest growing type of cancer in the United States. We report here the synthesis of a novel series of quinazolinylmethoxybenzene derivatives 1a-c and their antiproliferative activities against A375 human melanoma cell line. Among them, urea compound 1a (IC50 = 4.8 μM) having 4-chloro-3-trifluoromethylphenyl moiety showed superior antiproliferative activity to Sorafenib (IC50 = 5.5 μM) as a reference compound. These results will helpful for designing structure of a therapeutic agent for the treatment of melanoma.
The effects of La addition to Ni/CeO2 methane partial oxidation catalysts were investigated. Catalysts were prepared by the impregnation and urea methods. In the preparation of catalysts, La content was changed from 1 wt% to 3wt%. Catalysts that contain 2wt% La showed the highest methane conversion of about 80% and CO selectivity of 84% and H2 selectivity of 70%. This result may be stemmed from that, when La content is 2wt%, a fluorite oxide-type structure is well formed and carbon deposition is also decreased. Among the catalysts, 2.5wt% Ni/Ce(La)Ox showed the highest catalytic activity. From the experiment of changing reaction temperature with 2.5wt% Ni/Ce(La)Ox catalyst, it was found that the optimum reaction temperature is 750℃ and at this temperature methane conversion was about 90%, CO and H2 selectivities were 94 and 80%, respectively.
The objective of this study was to evaluate the antifungal properties of xanthorrhizol (extract from curcuma xanthorrhiza) against Candida albicans. Some of the commercial products were evaluated for their ability to inhibit growth of C. albicans. OTC product containing povidone iodide and cosmetic grade product with surfactants were tested. Antifungal activity was shown in 1.56% of OTC product, however, there was no antifungal effect in cosmetic product. For the comparison, we tested several materials. Povidone iodide, lemon tea tree oil and xanthorrhizol showed antifungal activities against C albicans in 0.25, 0.062 and 0.007%, respectively. We also tested the antifungal effects of povidone iodide and xanthorrhizol in surfactant base. Test results revealed that 2.5% of povidone iodide and 0.156% of xanthorrhizol showed similar antifungal effects. These findings support the application of xanthorrhizol for vaginal cleanser or personal cares using antifungal effect.
본 논문에서는 6,13-bis (triisopropylsily lethynyl)-pentacene (TIPS-pentacene) 유기 박막 트랜지스터에 니켈 버퍼층을 적층했을 때의 효과를 연구하였다. 니켈 (Nickel) / 은(Silver) 소스 드레인 전극은 은 (Silver) 전극이 단독으로 쓰일 때 보다 에너지 레벨차이를 줄여 캐리어의 주입이 더 잘되도록 도와주므로써 전기적 특성을 향상 시켜준다. 또한 유기 게이트 절연체의 추가로 TIPS-pentacene 은 규칙적 배열된 형태를 가지므로써 소자 성능의 향상을 가지고 온다. 제작한 유기박막트랜지스터 에서 0.01 cm2의 포화영역 이동도를 얻을 수 있었으며, 또한 드레인 전압을 50 V로 하고 게이트 전압을 20 V에서 -50 V 까지 인가하였을 때 2×104의 전멸 비를 얻을 수 있었다. 이러한 결과를 polyethylene terephthalate (PET) 기판을 이용한 유연한 OTFTs 에 적용시켜본 결과 유리기판위에 제작했을 때와 비슷한 성능을 얻음을 확인하였다.
본 논문은 메탈 이중층 전극을 이용한 유기 박막 트랜지스터를 제작하여 Au나 Ag 금속만으로 제작한 일반적인 유기 박막 트랜지스터와의 전기적 특성을 비교하였다. 전기적 특성에서 게이트 절연층은 높은 K 값을 갖는 Al2O3를 사용하였고, 유기 반도체층은 펜타센을 사용하였다. 본 실험에서 제작한 유기 박막 트랜지스터는 1.6 × 10-1 cm2의 포화영역 이동도를 얻을 수 있었으며, 또한 드레인 전압을 -5V로 하고, 게이트 전압을 3 V에서 -10 V 까지 인가하였을 때 3×105의 전멸 비를 얻을 수 있었다.
Titanium dioxide particles are used as photocatalysts, sensors, adsorbents and catalyst. Core-shell polymers of inorganic/organic pair, which have both core and shell component, were synthesized by sequential emulsion polymerization using Acrylate as a shell monomer and potassium persulfate (KPS) as an initiator. We found that when Acrylate core prepared by adding 0.5~2.0 wt% EU-S133D, Titanium dioxide / Acrylate core-shell polymerization was carried out on the surface of Titanium dioxide particle without forming the new Titanium dioxide particle during acrylate shell polymerized in the inorganic/organic core-shell polymer preparation. The structure of core-shell polymer were investigated by measuring to the thermal decomposition of polymer composite using thermogravimetric analyzer(TGA) and morphology of latex by scanning electron microscope(SEM).
This study is focused on the modeling of two phase fluid flow system in the electrode of hydrogen gas generator. The characteristics of hydrogen gas generation was studied in view of efficiency of hydrogen gas generation rate and a tendency of gas flow through the riv of electrode. Since the flow rate of generated gas is the most crucial in determining the efficiency of hydrogen gas generator, we adopted the commercial analytical program of COMSOL MultiphysicsTM to calculate the theoretical flow rate of hydrogen gas from the outlet of gas generator.
Scale generation in the inside of a pipe IS restricted by reduction and oxidation(REDOX) reaction of alloyed metal of Cu-Zn. To measure the scale generating rate in the 1.67 mm of inside diameter of stainless steel tube, 300 ppm of CaCO3 solution is circulated in the REDOX reactor and stainless steel tube in the order. In the case of CaCO3 solution treated by REDOX reactor, flowing is maintained without plugging in the stainless steel tube, and the concentration of Cu and Zn in the circulating solution showed less than 1 ppm, which is equal to that of untreated by REDOX reactor. The crystal type of CaCO3 generated by crystalline nucleus of Cu or Zn, mostly showed aragonite type.
This study was conducted to evaluate the effects of dietary Korean red pine bark extract as an antibiotic replacements on cholesterol, fatty acids and the shelf-life of chicken meat. To accomplish this, chickens were fed the optimal level of red pine bark extract that was found to replace antibiotics in the diet of broilers. A total of 180 male broilers(Ross strain 308) were divided into three treated groups, T1(control group), T2(8 ppm of avilamycin) and T3(65 ppm of red pine bark extract per kg diet). The lipid content was reduced by 24.67% and 20.49% in T3 group, while the cholesterol level also decreased significantly in the T3 group by 20.49% and 20.55% when compared to the T1 and T2 groups, respectively. In addition, the saturated fatty acid level was lower in the T3 group than in the T1 and T2 groups, while the unsaturated fatty acid level of the T3 group was significantly higher than those of the other groups. The TBARS value of chicken thigh muscle containing its skin on the 7th day of low temperature storage was significantly lower by 23.86% and 21.17% in the T3 group than in the T1 and T2 groups, respectively. Evaluation of the color of the meat revealed that the L*value (lightness) and b*value(yellowness) were higher in the T3 group than in the T1 and the T2 groups, but that the pH was significantly lower in the T3. Based on the results of this study, the addition of 65 ppm red pine bark extract to the diet of broilers should improve their meat quality with respect to the lipid contents and shelf-life when compared to the addition of antibiotics.
Silicone surfactants are widely used in many industrial area because of its thermal stability and lower foaming property. But it has limitation to expand the application because of migration and bubble generation issues when it is mixed with organic surfactant. In this study, epoxy functionalized fluoro-silicone surfactant, perfluoro glycidoxypropyl polyether siloxane(PFGES), was synthesized using hydrosilylation reaction among perfluoro methyl hydrogen siloxane, allyl glycidyl ether, and allyl ployether in order to get lower surface tension, better thermal stability than conventional silicone surfactant, and reactivity with anhydride function.
Silicone dioxide absorbed polyoxyethylene alkylether sulfate (EU-S75D) surfactant was prepared. The core-shell composite of inorganic/organic were polymerized by using styrene(St) as a shell monomer and potassium persulfate(KPS) as an initiator. We studied the effect of surfactants on the core-shell structure of silicone dioxide/styrene in the presence of an anionic surfactant lauryl sulfate(SLS). The structure of core-shell polymer were investigated by measuring to the thermal decomposition of polymer composite using thermogravimetric analyzer(TGA) and morphology of latex by scanning electron microscope(SEM).