• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.2
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• pp.900-903
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• 2003

Using $DV-X{\alpha}$ method, it is calculated that nickel reduces the energy band gap of manganese oxide in 3 additives of titanium, nickel and tin. Therefore, it is estimated that the electrical conductivity of manganese-nickel oxide has the lowest value in 3 kinds of manganese oxide. The manganese oxide and manganese-nickel oxide which were produced by anodic deposition under $30mA/cm^2$ at room temperature in manganese sulfate and manganese-nickel sulfate solution were thermal-analyzed by DTA and TGA. The weight change of manganese oxide continuously decreased below $508^{\circ}C$ and kept constant at $518{\sim}600^{\circ}C$. However, the manganeses-nickel oxide transformed at the temperature range of $510{\sim}537^{\circ}C$. It is observed that the nickel addition to manganese oxide increases transformation temperature and its range.

• Toxicological Research
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• 제11권2호
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• pp.303-308
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• 1995

Nitric oxide, a physiological transmitter, is reported to mediate cellular injury in various tissues. Its reactivity to free radical is believed to be one of the reasons for its involvement in cytotoxicity. Menadione, a representative quinone, is cytotoxic to several cell systems including isolated hepatocyte, endothelial cell and red blood cells. Its toxic mechanism is related to oxidative stress, mediated by toxic free radicals. Our previous studies demonstrated that menadione induced cell lysis and increase of oxygen consumption in platelets. It has been reported that platelets have nitric oxide producing enzyme, nitric oxide synthase. Thus, we have investigated to manifest the role of nitric oxide.in menadione-induced cytotoxicity in rat platelets. Menadione induced cytotoxicity in platelets was unaffected by $N^G$-nitro-arginine methyl ester (L-NAME), selective and competitive inhibitor of nitric oxide synthase. We also invesitgated the role of extracellular nitric oxide in menadione-induced cytotoxicity of platelets by addition with sodium nitroprusside (SNP). SNP did not affect platelet cytotoxicity by menadione. These results suggested that nitric oxide which was generated endogeneously or exogeneously might have a negligible role in menadione-induced cytotoxicity in rat platelets.

• 전자공학회논문지A
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• 제32A권9호
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• pp.121-127
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• 1995

We have analyzed the double insulating layer consisting of anodic oxide and ZnS through TEM experiments. The use of double insulating layer for HgCdTe surface passivation is one of the promising passivation method which has been recently studied deeply and the double insulating layer is formed by the evaporation of ZnS on the top of anodic oxide layer grown in H$_{2}$O$_{2}$ electrolyte. The structure of anodic oxide layer on HgCdTe is amorphous but the structure of oxide layer after the evaporation of ZnS has been changed to micro-crystalline. The interface layer of 150.angs. thickness has been found between ZnS and anodic oxide layer and is estimated to be ZnO layer. The results of analysis on the chemical components of ZnS, the interface layer and anodic oxide layer have showed that Zn has diffused into the anodic oxide layer deeply while Hg has been significantly decreased from HgCdTe bulk to the top of oxide layer. The formation of ZnO interface layer and the change of structure of anodic oxide layer after the evaporation of ZnS are estimated to be defects or to induce the defects which might possibly affect the increase of the positive fixed charges shown in C-V measurements of HgCdTe MIS.

• 한국표면공학회지
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• 제47권4호
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• pp.155-161
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• 2014

The present work is concerned with the formation behavior of anodic oxide films on Al7075 alloy under a galvanostatic condition in 20 vol.% sulfuric acid solution. The formation behaviour of anodic oxide films was studied by the analyses of voltage-time curves and observations of colors, morphologies and thicknesses of anodic films with anodization time. Hardness of the anodic oxide films was also measured with anodization time and at different positions in the anodic films. Six different stages were observed with anodiziation time : barrier layer formation (stage I), pore formation (stage II), growth of porous films (stage III), abnormal rapid oxide growth (stage IV), growth of non-uniform oxide films (stage V) and breakdown of the thick oxide films under high anodic voltages (stage VI). Hardness of the anodic oxide films appeared to decrease with increasing anodization time and with the position towards the outer surface. This work provides useful information about the thickness, uniformity, imperfections and hardness distribution of the anodic oxide films formed on Al7075 alloy in sulfuric acid solution.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1998년도 Proceedings of UNESCO-internetwork Cooperative Regional Seminar and Workshop on Bioassay Guided Isolation of Bioactive Substances from Natural Products and Microbial Products
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• pp.145-145
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• 1998

In the present study, we have demonstrated that taurine could stimulate the production of nitric oxide and the activity of ERK2 (extracellular signal regulated protein kinase or pp42 MAP kinase). Nitric oxide(NO), the product of inducible nitric oxide synthase(iNOS), is known to be implicated in the metabolism of bone. ERK cascade plays a key role in the gene expression of iNOS in osteoblastic cell. We investigated whether taurine (l-20mM) could stimulate ERK2 activity, nitric oxide production, and inducible nitric oxide synthase in osteoblast-like UMR-106 cells. Nitric oxide was measured spectophotometrically as nitrite and the activation of ERK2 and iNOS was studied using Western 145 blot analysis. Taurine increased the production of nitric oxide in a dose-dependent manner and the effect was reached to a maximum at 10 mM. The activation of iNOS were consistent with NO levels. The tyrosine phosphorylation of ERK2 was increased by taurine in a time-dependent manner. The these result suggest that taurine might stimulate the production of nitric oxide in osteoblast-like cells by the activation of ERK2 and could regulate the metabolism of bone via nitric oxide.

• Corrosion Science and Technology
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• 제7권3호
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• pp.145-151
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• 2008

Material degradation such as high temperature oxidation of metallic material is a severe problem in energy generation systems or manufacturing industries. The metallic materials are oxidized to form oxide films in high temperature environments. The oxide films act as diffusion barriers of oxygen and metal ions and thereafter decrease oxidation rates of metals. The metal oxidation is, however, accelerated by mechanical fracture and spalling of the oxide films caused by thermal stresses by repetition of temperature change, vibration and by the impact of solid particles. It is therefore very important to investigate mechanical properties and adhesion of oxide films in high temperature environments, as well as the properties in a room temperature environment. The oxidation tests were conducted for Ni and Ni-Co alloy under high temperature corrosive environments. The hardness distributions against the indentation depth from the top surface were examined at room temperature. Dynamic indentation tests were performed on Ni oxide films formed on Ni surfaces at room and high temperature to observe fractures or cracks generated around impact craters. As a result, it was found that the mechanical property as hardness of the oxide films were different between Ni and Ni-Co alloy, and between room and high temperatures, and that the adhesion of Ni oxide films was relatively stronger than that of Co oxide films.

• KSBB Journal
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• 제15권6호
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• pp.630-634
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• 2000

에폭사이드 가수분해효소 활성이 우수한 Aspergillus niger 를 생촉매로 이용하여 업체선택적 가수분해 반응을 통해 라세믹 styrene oxide 기질로부터 광학활성 (S)-styrene oxide를 생산하는 실험을 수행하였다. (R)-styrene oxide 이성질체에 대한 초기 가수분해 속도에 영향을 주는 실험인자들인 pH, 반응온도, cosolvent 첨가량 등에 대해 중심합성계획법을 이용한 반응표면 분석을 통해 가수분해반응 속도를 향상시킬 수 있는 최적 반응조건을 결정하였다. pH 7.78, 반응온도 2 $28.32^{\circ}C$ 및 cosolvent 첨가량 2.4% (v/v)의 조건에서 약 10시간 정도의 반응을 통해 ee 값이 100%인 광학적으로 순수한 (S)-styrene oxide를 35% 정도(이론수율 = 50%)의 높은 수율로 얻을 수 있었다.

• 한국임상수의학회지
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• 제20권4호
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• pp.458-466
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• 2003

The bone regeneration effects of copper oxide on experimentally induced fibular fracture were examined in 36 New Zealand white male rabbits. They were divided into two groups: non-treated group (control group) and copper oxide treated group (treatment group). A fibular fracture was created by an osteotomy in the middle of the fibula and 62.5 mg/kg of copper oxide was orally administrated during 7 days after operation in the treatment group. Radiological findings, histopathological examinations and hematoserological findings were observed to evaluate the bone regeneration effects of copper oxide on fibula fracture during 9 weeks. In radiological findings, the area of bone regeneration at the fracture site of the treatment group was significantly wider from 3 weeks to 6 weeks after administration of copper oxide than those of the control group (p < 0.05). In histopathological examinations, fracture healing in treatment group was faster than in control group. Also, histopathological responses of thick bony trabeculae and new bone marrow formation were shown in the treatment group, whereas many fibrous tissues and cartilages were mainly observed in the control group. No specific effects of copper oxide on the body was found in hematological and serological test during experimental period. These results showed that the copper oxide had a potential therapeutic application in the treatment of fracture and bone trauma.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.363-363
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• 2010

After oxide wet etch with BOE(Buffered Oxide Etchant), triangle type defect maps were inspected and SEM image showed them unetch of oxide layer. As decreasing design rule, oxide unetch has become a crucial issue and has affected the yield and quality.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.437-437
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• 2014

Various oxide particles are synthesized in an ambient condition using an electron beam irradiation system. The formation of oxide particles is confirmed by FT-IR spectra results and the X-ray photoelectron spectrum. It is also shown that the morphology and size of oxide particles are significantly influenced by the type and flowrate of dilution gas. The energy dispersive X-ray (EDX) analysis also confirms that various oxide particles are synthesized.