• Korean Journal of Materials Research
• /
• v.11 no.3
• /
• pp.184-184
• /
• 2001

The effect of neutral ligand(L) on the precursor characteristics of (hfac)Cu(I)-L and on Cu MOCVD Process was studied. The neutral ligands of (hac)Cu(I)-L$_{x}$, such as ATMS(allytrimethylsilane), VTMS(vinyltrimethylsilane), VCH(vinylcyclohexane), MP(4-methyl-1-pentene), ACP(allylcyclopentane), and DMB(3,3-dimethyl-1-butene) were investigated. When the dissociation temperature of Cu(I)-L bond is low, low temperature deposition below $100^{\circ}C$ is possible and the resistivity of the film is low. But thermal stability of the precursor is low in this case. The resistivity is almost the same regardless of L at the deposition temperature range of $125~175^{\circ}C$. The resistivity is increased as the molecular weight of L becomes higher above $225^{\circ}C$ The vapor pressure of the precursor was closely related to the boiling point of L, the lower the boiling point of L, the higher the vapor pressurere.

• Korean Journal of Materials Research
• /
• v.11 no.3
• /
• pp.185-190
• /
• 2001

The effect of neutral ligand(L) on the precursor characteristics of (hfac)Cu(I)-L and on Cu MOCVD Process was studied. The neutral ligands of (hac)Cu(I)-L$_{x}$, such as ATMS(allytrimethylsilane), VTMS(vinyltrimethylsilane), VCH(vinylcyclohexane), MP(4-methyl-1-pentene), ACP(allylcyclopentane), and DMB(3,3-dimethyl-1-butene) were investigated. When the dissociation temperature of Cu(I)-L bond is low, low temperature deposition below $100^{\circ}C$ is possible and the resistivity of the film is low. But thermal stability of the precursor is low in this case. The resistivity is almost the same regardless of L at the deposition temperature range of $125~175^{\circ}C$. The resistivity is increased as the molecular weight of L becomes higher above $225^{\circ}C$ The vapor pressure of the precursor was closely related to the boiling point of L, the lower the boiling point of L, the higher the vapor pressurere.

• Journal of Plant Biotechnology
• /
• v.35 no.2
• /
• pp.115-120
• /
• 2008

L-Ascorbic acid (vitamin C) in vegetables is an essential component of human nutrition. The objective is to transform lettuce (Lactuca sativa L.) with GalUR gene that is involved in the vitamin C biosynthesis. The cotyledons of Hwoahong (Nongwoo Bio Co.) were used to induce the callus and shoot under the selection media with MS + 30 g/L Sucrose + 0.5 mg/L BAP + 0.1 mg/L NAA + 100 mg/L kanamycin + 200 mg/L lilacillin, pH 5.2. The shoot was developed from the cut side of the explants after 3 weeks on the selection media. We successfully transformed the lettuce with GaIUR gene and analyzed the levels of vitamin C. We found that some of the lettuce transgenic lines contained higher levels of vitamin C compared with the normal one (non-transformed). Especially, some of $T_1$ lettuces inserted by GalUR showed about $3{\sim}4$ times higher content of vitamin C compared to the non-transformed lettuce. This data support the previously work performed with GLOase transgenic $T_1$ lettuces from which several times higher content of vitamin C were identified. The $T_2$ lettuces with high content of vitamin C have been selected for further analysis.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.22 no.4
• /
• pp.381-391
• /
• 1993

To evaluate the antioxidizing effect of flavonoid on fish oil and peroxidized fish oil, rats were fed with diets containing 5% corn oil (CO), 5% corn oil and 15% fresh fish oil (FO) or peroxidixed fish oil (PFO) for 4weeks. An half of FO and PFO group rats were injected with 10mg flavonoid (+)-catechin (a day per kg body weight) (FO-C and PFO-C). FO and FO-C group rats showed higher increase in body weight as compared to PFO, PFO-C group rats. Whereas, the opposite result was obtained in case of liver weight increase. In addition, catechin apparently reduced liver weight by 12~17%. Phospholipid, cholesterol, triglyceride and lipid peroxide content in serum and cholesterol, lipid peroxide content in liver and adipose tissue of PFO, PFO-C group rats were significantly higher than those of FO, FO-C one. These results suggested that catechin reduced the synthesis of lipid and protected effectively against lipid peroxidation. In fatty acids profile of neutral lipid and phospholipid, the ratio of polyunsaturated fatty acids (PUFA) versus saturated fatty acids (SFA) in PFO, PFO-C were lower than that of FO or FO-C because of ruduced PUFA. Contrary to our expectation, the enzyme activities of superoxide dismutase(SOD), catalase and glutathione peroxidase (GSH-Px) in rat liver of FO and FO-C group were lower than those of PFO and PFO-C group. These results were quite interesting and might be explained in terms of homeostasis. In case of total lipid in liver, $C_{20:5}$, $C_{22:6}$ fatty acids were decreased in rat fed peroxidized fish oil. In conclusion, catechin was considered to be an antioxidative and hepatoprotective drug and hypolipidemic agent.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.5 no.1
• /
• pp.17-22
• /
• 2010

Generally, there are Chua's Circuit, Lorenz Circuit and Duffing circuit in the chaos circuit. Among these chaos circuits, Chua's circuit is well known to make the electronic parts easily. Chua's circuit is the constitute of the linearelements. These are constitute of Resistor component(R), inductor component(L), capacitor(C), and nonlinear element which is constitute of nonlinear resistor. However, L element have a difficult problem to implement real hardware by using commercial parts. Due to this, it has a saturation characteristic. In this paper, we analyzed the simplified Chua's circuit which is replace L to C by PSPICE program. Because L element has a difficult problem to make a real hardware, L has a saturation characteristic and we also confirm this analysis as the result.

• Journal of Korean Society of Environmental Engineers
• /
• v.28 no.5
• /
• pp.501-510
• /
• 2006

To investigate the effects of MLSS concentration and influent C/N ratio on the nitrogen removal efficiency of alternately intermittently aerated nonwoven fabric filter bioreactors, the MLSS concentrations of the reactors were maintained at approximately 5,500 mg/L, 10,000 mg/L and 15,000 mg/L, and the influent TCOD/TKN ratio was decreased gradually from 5 to 2 by adding $NH_4Cl$. The influent was prepared by diluting a food waste leachate to a TCOD concentration of about 300 mg/L. The results of the experiment showed F/M ratios less than 0.112 g TCOD/g MLSS-day, average TCOD removal efficiencies of above 95%, and an average observed microbial yield coefficient of 0.283 g MLSS/g COD removed. The nitrification efficiencies were computed to be always better than 96% except one case where the nitrification efficiency was 90.5% when the MLSS concentration and the influent TCOD/TKN ratio was 5,500 mg/L and 2, respectively. The denitrification efficiency deteriorated as the influent TCOD/TKN ratio decreased. The average denitrification efficiency at the MLSS concentration of 10,000 mg/L was 10.7% better than that at the MLSS concentration of 5,500 mg/L, and the denitrification rate improved at a rate of 2.66 mg NL as the MLSS concentration increased by 1,000 mg/L. When the MLSS concentration was 15,000 mg/L, however, the average denitrification efficiency was merely 4.6% higher compared to when the MLSS concentration was 5,500 mg/L, and the denitrification rate increased at a rate of 0.75 mg N/L per 1,000 mg/L MLSS increase. Therefore, no strict proportional relationship was found between MLSS concentration and endogenous denitrification rate. The average alkalinity consumption rate was 3.36 mg alkalinity/mg T-N removed, which is similar to the theoretical value of 3.57 mg alkalinity/mg T-N removed, but the rate increased as the influent TCOD/TKN ratio decreased.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.34 no.10
• /
• pp.1625-1632
• /
• 2005

This study was conducted to monitor the extraction yields and functional properties from cabbage by a response surface methodology. The extract yield was maximized as 44.47$\%$ under the temperature of 79.86$^{\circ}C$, ethanol concentration of 56.84$\%$ and solvent to sample ratio 25.58 mL/g . The maximum value of electron donating ability was 85.46$\%$ at 46.38$^{\circ}C$,57.06$\%$ of ethanol concentration and 27.71 mL/g of solvent to sample ratio. The maximum value of tyrosinase inhibitory effect was 69.37$\%$ at 37.5$^{\circ}C$,47.71$\%$ of ethanol concentration and 16.03 mL/g of solvent to sample ratio. The maximum value of SOD-like activity was 48.36$\%$ in 66.12$^{\circ}C$, 70.35$\%$ of ethanol concentration and 29.13 mL/g of solvent to sample ratio. Estimated conditions for the maximized extraction including yield, electron donating ability and SOD-like activity were 20 $\∼$ 30 mL/g in ratio of solvent to sample, 25$\∼$85$\%$ in ethanol concentration, and 40$\∼$90$^{\circ}C$ in extraction temperature.

• 전기의세계
• /
• v.12
• /
• pp.30-34
• /
• 1963

비선형자기철심을 사용한 inductance를 그 비선형영역까지 동작하게 할때와 직렬형가포화 reactor에 R-C부하를 직렬로 연결하여 동작시킬 때 어떠한 동작범위에서는 회로의 전류진폭이 불안정한 경우가 있다. 특히 직렬형가포화 reactor에 R-C부하를 연결한 경우는 J.T.Salihi씨 및 H.C.Bourne씨에 의하여 그 동작현상이 설명되었다. 그러나 안정조건은 충분한것이 아니라고 생각되며 이와같은 R-L-C 직렬회로는 정량적으로 해석하는데 수학적인 난점이 있어서 곤란하지만 정성적인 방법 즉 근사계산에 의하여 안정성문제와 그 회로동작상태 등을 고찰할 수 있다. 본 고는 이러한 안정조건을 계산하여 제시코져 한다.

• Journal of the Korean Geotechnical Society
• /
• v.17 no.5
• /
• pp.173-180
• /
• 2001

이방압밀이 실트질모래의 정적재하에 의한 유동파괴거동에 미치는 영향을 연구하기 위하여 비배수삼축압축시험을 수행하였다. 이를 위하여 상대밀도가 약 17%인 공시체를 습윤다짐방법에 의해서 성형하고 4가지의 압밀응력비, 1.0, 0.7, 0.55, $K_{o}$ 로서 압밀시켰다. 시험결과로서 정상상태선은 p-q 공간상에서 압밀응력비에 관계없이 유일한 직선이며 collapse line의 기울기는 압밀응력비가 증가함에 따라 선형적으로 감소한다는 사실을 보여준다. 또한, 유동파괴거동을 보이는 느슨하게 다져진 실트질모래의 잔류강도($S_{us}$ )와 첨두강도($S^{p}$ )와의 관계는 압밀응력비의 크기에 관계없이 $S_{p}$ /$p_{c}$ = $A_{L}$ +$B_{L}$ ($S_{us}$ /$p_{c}$ )로 표현되는 일반식으로 나타낼 수 있으며 계수 $A_{L}$ 및 $B_{L}$은 압밀응력비의 크기에 따라 선형적으로 변하는 경향을 나타낸다.

• Food Science and Preservation
• /
• v.17 no.2
• /
• pp.281-289
• /
• 2010

We determined the optimum ethanolic conditions for extraction of $\gamma$-oryzanol and other functional components from rice bran, using response surface methodology (RSM). A central composite design was used to investigate the effects of the independent variables of solvent ratio ($X_1$), extraction temperature ($X_2$), and extraction time ($X_3$), on dependent variables including yield ($Y_1$), total phenolic content ($Y_2$), electron-donating activity ($Y_3$), ferulic acid level ($Y_4$), and $\gamma$-oryzanol concentration ($Y_5$). Solvent ratio and extraction temperature were the most important factors in extraction. The maximum yield was at 22.56 mL/g ($X_1$), 78.19C ($X_2$), and 522.15 min ($X_3$), at the saddle point. Total phenolic levels were little affected by solvent ratio or extraction temperature. The maximum concentration of extracted total phenolics was 90.78mg GAE/100 g at 21.26 mL/g, $94.65^{\circ}C$, and 567.97 min. A maximum electron-donating ability of 54.72% was obtained with the parameters 20.20 mL/g,$81.89^{\circ}C$, and 701.87 min, at the highest point. The maximum level of ferulic acid components was 210.47 mg/100g at 5.22 mL/g, $79.66^{\circ}C$, and 575.24 min. In addition, the maximum $\gamma$-oryzanol concentration was 660.39 mg/100g at 5.10 mL/g, $81.83^{\circ}C$, and 587.39 min. The optimum extraction conditions were a solvent ratio of 10.45 mL/g, $80^{\circ}C$ extraction temperature, and 535 min extraction time. Predicted extraction levels under optimized conditions were in line with experimental values.