• 한국재료학회지
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• 제2권1호
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• pp.35-42
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• 1992

실릴콘 산화막을 $CHF_3/C_2F_6$ 혼합가스를 사용하여 반응성이온 건식식각을 행할 때 실리콘 표면에 형성되는 잔류막과 손상충의 열적 거동을 X-선 광전자 분광기(XPS)와 이차이온 질량 분석기 (SIMS)를 사용, 연구하였다. 저항가열을 통한 in-situ 분석에 의해 폴리머 잔류막은 $200^{\circ}C$부터 분해가 시작되고 $400^{\circ}C$ 이상의 가열에서는 graphite 형태의 탄소 결합체를 형성하며 분해됨을 알았다. 질소 분위기하의 급속 열처리를 통해 잔류막의 열분해는 $800^{\circ}C$ 이상에서 완료되고 손상층을 형성하는 침투 불순원소의 기판 외부로의 확산이 관찰되었다.

• 자원환경지질
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• 제42권6호
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• pp.561-574
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• 2009

본 연구에서는 농업지역에서의 양수, 관개, 탈질작용을 고려한 불포화대 및 포화대 지하수 흐름 및 용질이동 모델인 VSFRT2D(Variably Saturated Flow and Reactive Transport model)를 개발하였다. VSFRT2D는 Richards equation을 지하수 흐름 지배방정식으로 이용하며, Thornthwaite 방법을 이용하여 강수가 일어나지 않을 때 지표면 증발산량 계산 절차를 포함하는 새로운 모델을 개발함으로써 기존의 불포화대 모델을 개선하였다. 또한 Monod kinetics에 기반한 생분해 기작을 네 개의 비선형 오염물 거동식과 세 종류의 미생물 거동식을 이용함으로서 탈질작용을 이 모델에 반영하였다. 개발된 모델을 질산성질소로 오염된 홍성 지역의 현장 관측 자료에 적용하였다. 본 연구에서는 강수, 양수, 증발산, 관개, 비료 투여 및 다양한 생분해 과정들이 지하수 흐름 및 오염물 거동에 미치는 효과들을 확인하기 위하여 각각의 과정을 개별적으로 나누어서 수치 모의한 후 각각의 결과를 상호 비교하였다. 수치 모의 결과 이 지역에서의 질산성 질소 농도 변화는 생분해에 의한 영향은 매우 미미하게 나타났다. 반면에 관개에 의한 양수, 강수, 질소 비료 시비에 의해서는 크게 영향을 받았다.

• 대한본초학회지
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• 제30권4호
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• pp.89-94
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• 2015

Objectives : It had been reported that herbal medicines containing polyphenol and flavonoid have been shown to be associated with decreased the cause of aging and variety of disease such as reactive nitrogen species and reactive oxygen species in several recent studies. Salviae miltiorrhizae Radix, origined fromSalvia miltiorrhizaBGE., is one of popular traditional herbal medicines that is commonly used by traditional medicine practitioners. To this date, Salviae miltiorrhizae Radix has more than 2000-year history of mature application. This study was conducted to investigate whether the Salviae miltiorrhizae Radix methanol extract has an inhibitory effect association with oxidation or inflammation.Methods : Cytotoxic activity of Salviae miltiorrhizae Radix methanol extract on RAW264.7 cells was evaluated by using 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide solution. Nitric oxide production was measured using griess reagent system. Western blot analysis and measurement for changes of protein expression, nitric oxide synthase and cyclooxygenase-2, also performed.Results : The medicinal plant, Salviae miltiorrhizae Radix, does not impair the cell viability in tested concentration (25-100 μg/ml). SMR showed anti-oxiative effectsin vitroby decreasing electron donating ability, and also showed anti-inflammatory effects suppressing NO and COX-2 expressin in LPS induced RAW264.7 activation. SMR inhibited the generation of intracellular ROS production as dose dependant manner.Conclusions : These results indicate that Salviae miltiorrhizae Radix methanol extract has an anti-inflammatory activities via anti-oxidative effects, and the anti-inflammatory effect was presentedd as dose dependant manner.

• BMB Reports
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• 제40권6호
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• pp.1039-1049
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• 2007

Overdoses of acetaminophen cause hepato-renal oxidative stress. The present study was undertaken to investigate the protective effect of a 43 kDa protein isolated from the herb Cajanus indicus, against acetaminophen-induced hepatic and renal toxicity. Male albino mice were treated with the protein for 4 days (intraperitoneally, 2 mg/kg body wt) prior or post to oral administration of acetaminophen (300 mg/kg body wt) for 2 days. Levels of different marker enzymes (namely, glutamate pyruvate transaminase and alkaline phosphatase), creatinine and blood urea nitrogen were measured in the experimental sera. Intracellular reactive oxygen species production and total antioxidant activity were also determined from acetaminophen and protein treated hepatocytes. Indices of different antioxidant enzymes (namely, superoxide dismutase, catalase, glutathione-S-transferase) as well as lipid peroxidation end-products and glutathione were determined in both liver and kidney homogenates. In addition, Cytochrome P450 activity was also measured from liver microsomes. Finally, histopathological studies were performed from liver sections of control, acetaminophen-treated and protein pre- and post-treated (along with acetaminophen) mice. Administration of acetaminophen increased all the serum markers and creatinine levels in mice sera along with the enhancement of hepatic and renal lipid peroxidation. Besides, application of acetaminophen to hepatocytes increased reactive oxygen species production and reduced the total antioxidant activity of the treated hepatocytes. It also reduced the levels of antioxidant enzymes and cellular reserves of glutathione in liver and kidney. In addition, acetaminophen enhanced the cytochrome P450 activity of liver microsomes. Treatment with the protein significantly reversed these changes to almost normal. Apart from these, histopathological changes also revealed the protective nature of the protein against acetaminophen induced necrotic damage of the liver tissues. Results suggest that the protein protects hepatic and renal tissues against oxidative damages and could be used as an effective protector against acetaminophen induced hepato-nephrotoxicity.

• 동의생리병리학회지
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• 제25권3호
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• pp.471-481
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• 2011

Clove has been frequently used as anti-diabetic, anti-microbial, anti-inflammatory, anesthetic drug and remedies for stomachache by coldness. In this study, the antioxidant activity of extract from Clove was studied in vitro methods by measuring the antioxidant activity by TEAC, measuring the scavenging effects on reactive oxygen species (ROS) [superoxide anion, hydroxyl radical] and on reactive nitrogen species (RNS) [nitric oxide and peroxynitrite] as well as measuring the inhibitory effect on $Cu^{2+}$-induced human LDL oxidation. Anti-platelet aggregation and anti-thrombotic effects of Clove extracts were studied ex vivo methods by mesuring the inhibitory effect on thrombin induced platelet aggregation and the fibrinolytic activity. The Clove extracts were found to have a potent scavenging activity, as well as an inhibitory effect on LDL oxidation in vitro. Moreover Clove extracts were exhibited remarkable inhibitory effect on platelet aggregation and fibrinolytic activity. In conclusion, the Clove extracts have anti-oxidative and anti-atherosclerotic effects in vitro and ex vivo system, which can be used for developing pharmaceutical drug against oxidative stress and atherosclerosis.

• 센서학회지
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• 제23권2호
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• pp.94-98
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• 2014

Aluminum nitride (AlN) thin films with a TiN buffer layer have been fabricated on SUS430 substrate by RF reactive magnetron sputtering at room temperature under 25~75% $N_2$ /Ar. The characterization of film properties were performed using surface profiler, X-ray diffraction, X-ray photoelectron spectroscopy(XPS), and pressure-voltage measurement system. The deposition rates of AlN films were decreased with increasing the $N_2$ concentration owing to lower mass of nitrogen ions than Ar. The as-deposited AlN films showed crystalline phase, and with increasing the $N_2$ concentration, the peak of AlN(100) plane and the crystallinity became weak. Any change in the preferential orientation of the as-deposited AlN films was not observed within our $N_2$ concentration range. But in the case of 50% $N_2$ /Ar condition, the peak of (002) plane, which is determinant in pressure sensing properties, appeared. XPS depth profiling of AlN/TiN/SUS430 revealed Al/N ratio was close to stoichiometric value (45:47) when deposited under 50% $N_2/Ar$ atmosphere at room temperature. The output signal voltage of AlN sensor showed a linear behavior between 26~85 mV, and the pressure-sensing sensitivity was calculated as 7 mV/MPa.

• 한국자기학회지
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• 제6권5호
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• pp.317-322
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• 1996

RF magnetron reactive sputtering 법으로 Fe-Zr-N 박막을 제작하여 열처리 온도와 질소 분압의 변화에 따른 포화자화, 보자력, 고주파에서의 투자율 그리고 열적 안정성을 조사하였다. Fe-Zr-N 박막은 비정질과 결정질의 경계 조성인 $Fe_{72-78}Zr_{7-10}N_{15-18}$의 조성범위에서 연자성을 나타내었다. 이러한 박막은 포화자속밀도 1.55 T, 1 MHz에서의 실효 투자율은 3000 이상의 연자성을 나타내고 열처리 온도 $550^{\circ}C$ 까지도 실효투자율 2500 정도의 열적 안정성을 나타내었다. X-선 회절 분석 결과 열처리에 의해서 ZrN 미결정이 석출하여 $\alpha-Fe$ 결정 성장이 억제되어 우수한 연자기적 성질이 나타난다고 판단된다. 이때 $\alpha-Fe$ 입자 크기는 $40~50\AA$, ZrN의 입자 크기는 $10~15\AA$이었다.

• Journal of Acupuncture Research
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• 제32권1호
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• pp.1-11
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• 2015

Objectives : This study was performed to inquire into the protective effects of acupuncture on oxidative stress caused by cadmium accumulation in the kidney. Methods : Sprague-Dawley male($150{\pm}30g$) rats were stabilized for 1 week and divided into 5 groups: normal, control, $LR_3$ acupuncture, $BL_{23}$ acupuncture and sham acupuncture. For three days experimental groups received oral doses of cadmium 2 mg/kg twice a day. Acupuncture was applied bilaterally at each point 10 times for two weeks. The depth of stimulation was 1 mm at right angles and torsion of acupuncture was produced 2 times per second for 1 minute. The kidneys were extracted and weighed after two weeks, and renal function was confirmed through blood urea nitrogen(BUN). We measured reactive oxygen species of the serum and kidney, and compared expression levels of superoxide dismutase(SOD), catalase, glutathione peroxidase(Gpx), nuclear factor erythroid derived 2-related factor 2(Nrf-2), heme oxygenase-1(HO-1), nuclear factor-${\kappa}B$(NF-${\kappa}B)$, cyclooxygenase-2(COX-2), inducible nitric oxide synthase (iNOS), Bax and Cytochrome c. Results : The $LR_3$ acupuncture group and $BL_{23}$ acupuncture group experienced significantly increased kidney weight, and decreased BUN compared to control group. In terms of oxidative stress, the $LR_3$ acupuncture group and $BL_{23}$ acupuncture group experienced significantly reduced reactive oxygen species compared to the control group. Conclusions : The $LR_3$ acupuncture group and $BL_{23}$ acupuncture group experienced showed the effects of antioxidant, anti-inflammatory and apoptosis protection. The $BL_{23}$ acupuncture group was more effective than $LR_3$ acupuncture group.

• Journal of Electrical Engineering and Technology
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• 제4권1호
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• pp.55-65
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• 2009

Due to the rapid increase of electricity demand, consideration of environmental constraints in optimal power flow (OPF) problems is increasingly important. In Algeria, up to 90% of electricity is produced by thermal generators (vapor, gas). In order to keep the emission of gaseous pollutants like sulfur dioxide (SO2) and Nitrogen (NO2) under the admissible ecological limits, many conventional and global optimization methods have been proposed to study the trade-off relation between fuel cost and emissions. This paper presents an efficient decomposed Parallel GA to solve the multi-objective environmental/economic dispatch problem. At the decomposed stage the length of the original chromosome is reduced successively and adapted to the topology of the new partition. Two subproblems are proposed: the first subproblem is related to the active power planning to minimize the total fuel cost, and the second subproblem is a reactive power planning design based in practical rules to make fine corrections to the voltage deviation and reactive power violation using a specified number of shunt dynamic compensators named Static Var Compensators (SVC). To validate the robustness of the proposed approach, the algorithm proposed was tested on the Algerian 59-bus network test and compared with conventional methods and with global optimization methods (GA, FGA, and ACO). The results show that the approach proposed can converge to the near solution and obtain a competitive solution at a critical situation and within a reasonable time.

• 동의생리병리학회지
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• 제25권2호
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• pp.280-293
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• 2011

There is currently increased interest in the identification of antioxidant compounds that are pharmacologically potent and have low or no side effects. Plants produce significant amounts of antioxidants to prevent the oxidative stress caused by photons and oxygen, therefore they represent a potential source of new compounds with antioxidant activity. FARFARE FLOS has been frequently used on the respiratory system including bronchitis, phthisis. In this study, the antioxidant activity of extract from FF was studied in vitro methods by measuring the antioxidant activity by TEAC, measuring the scavenging effects on reactive oxygen species (ROS) [superoxide anion, hydroxyl radical] and on reactive nitrogen species (RNS) [nitric oxide and peroxynitrite] as well as measuring the inhibitory effect on Cu2+-induced human LDL oxidation. The FF extracts were found to have a potent scavenging activity, as well as an inhibitory effect on LDL oxidation. And this study was designed to evaluate whether FFEA may ameliorate oxidative stress and inflammatory status through the antioxidative mechanism in LPS-stimulated RAW 264.7 murine macrophage cell line. Treatment of RAW 264.7 cells with FFEA significantly reduced LPS-stimulated inflammatory response in a dose-dependent manner. In conclusion, the FF extracts have anti-oxidative and anti-inflammatory effects in vitro system, which can be used for developing pharmaceutical drug against oxidative stress and atherosclerosis.