• Title/Summary/Keyword: 산화질소생성

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The Effect of Silymarin and Ethanol Intake on Vascular Contractility (엉겅퀴 유래 Silymarin의 단독 및 알코올 병용 시 혈압 조절 효과)

  • Je, Hyun Dong;Min, Young Sil
    • Journal of Industrial Convergence
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    • v.20 no.7
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    • pp.131-137
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    • 2022
  • In the study, we endeavored to assess the convergence effect of Silybum marianum-derived silymarin and epidemiologically-correlated alcohol intake on vascular contractility and to determine the mechanism involved. There were few reports addressing the question whether thin or thick filament modulation is included in ethanol and silymarin-induced regulation. We hypothesized that ethanol at a low concentration and silymarin play a role in agonist-dependent regulation of vascular contractility. Denuded arterial muscles of Sprague-Dawley male rats were suspended in organ baths and isometric tensions were transduced and recorded using isometric transducers and an automatic data acquisition system. Interestingly, both silymarin and ethanol didn't encourage silymarin alone-induced inhibition in agonists-induced contraction suggesting that endothelial nitric oxide synthesis might be involved in ethanol or silymarin-induced modulation of vascular contractility and additional pathways besides endothelial nitric oxide synthesis such as ROCK inactivation might be involved in the silymarin-induced modulation of vascular contractility.

Characteristic Reactions in Anaerobic Nitrogen Removal from Piggery Waste (돈사폐수의 혐기성 질소제거공정에서 일어나는 특이반응)

  • Hwang, In-Su;Min, Kyung-Sok
    • Journal of Korean Society of Environmental Engineers
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    • v.28 no.3
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    • pp.300-307
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    • 2006
  • Anaerobic ammonium oxidation(ANAMMOX) is a novel process fur treatment of piggery waste with strong nitrogen. In this study, we investigated acid fermentation of organic matter, denitrificatiot reduction of sulfur compounds and P crystalization by hydroxyapatite during the treatment of wastewater with high strength of ammonium and organic matters by ANAMMOX process. Also, functions of hydroxylamine and hydrazine as intermedeates of ANAMMOX process were tested. This study reveals that various complex-reactions with anaerobic ammonium oxidation of piggery waste are happened and hydroxylamine and hydrazine play an important role in ANAMMOX reaction.

Antioxidant and anti-inflammatory effects of the ethyl acetate fraction of the Agastache rugosa extract (배초향 에틸아세테이트 분획의 산화방지 및 항염증 활성)

  • Kim, Bomin;Han, Yeong Eun;Lee, Hwa Jin
    • Korean Journal of Food Science and Technology
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    • v.49 no.3
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    • pp.331-337
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    • 2017
  • To evaluate the antioxidant activity of hexane, ethyl acetate, and butanol fractions obtained from Agastache rugosa extract, we measured the total polyphenol levels, DPPH radical scavenging activity, and reducing power. The ethyl acetate fraction of A. rugosa (AREA) displayed high phenolic levels, potent DPPH radical scavenging effect, and powerful reducing power. In addition, we examined the ability of AREA to inhibit nitric oxide (NO) production in lipopolysaccharide (LPS)-activated BV-2 microglia. AREA suppressed NO production and inducible nitric oxide synthase (iNOS) expression and downregulated interleukin-6 (IL-6) mRNA level in LPS-stimulated BV-2 microglia. Furthermore, we detected rosmarinic acid in AREA by HPLC, which suggested that rosmarinic acid could be one of the bioactive materials responsible for the antioxidant and anti-inflammatory activities of AREA. These results suggested that AREA may be a good source of functional foods with antioxidant and anti-inflammatory activities.

The Effect of the Hydrophobicity of Silicon Surface on the Formation of the Water Marks during HF-last Wet Chemical Processing (반도체 습식 HF 최종 공정 중 실리콘 표면의 소수성이 Water Mark형성에 미치는 영향)

  • Han, Jeong-Hun;Kim, Sung-Hwan;Park, Jin-Gu;Park, Jong-Jin
    • Korean Journal of Materials Research
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    • v.7 no.10
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    • pp.832-837
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    • 1997
  • 본 연구에서는 반도체 소자의 수율을 현저히 저하시키는 반도체 습식 세정 시 건조 후 웨이퍼 표면에 형성된 water mark의생성 원인을 고찰하였다. 이를 위해 초순수수의 물방울을 다른 접촉각의 시편 위에 고의로 잔류시킨 후 질소 및 산소 분위기에서 건조시켰다. 건조 분위기와 상관없이 HF 처리된 소수성의시편 뿐만 아니라 친수성의 시편에서도 water mark이 관찰되었다. 생성된 water mark의 크기는 분위기에 무관하게 접촉각이 증가함에 따라 감소하였다. 그러나 산소 분위기에서 HF처리된 시편은 건조 후 질소 분위기에서 생성된 water mark의 크기보다 2배이상 크게 형성되었다. 이들 산소 및 질소 분위기에서 HF 처리된 실리콘 시편 위에 생성된 water mark의 성분을 AES(Auger Electron Spectroscopy)로 분석한 결과 water mark는 실리콘과 산소의 화합물 형태로 존재함을 확인하였다. AAS(Atomic Absorption Spectroscopy)분석 결과 건조 분위기에 상관 없이 HF처리된 실리콘 시편 위에 물방울을 30분 잔류시 물방울 내의 실리콘 농도가 증가하였다. 또한 물방울내 ozone을 첨가하여 실리콘 표면을 산화 시켰을 때 물방울과 표면의 접촉각 감소와 water mark의크기의 증가를 초래하였다.

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Growth Characteristics of Nitrite Oxidizing Bacteria Isolated from Anaerobic Digestion Liquor (혐기소화액에서 분리한 아질산 산화세균의 생장특성)

  • Jang, Hyun-Min;Jang, Jae-Eun;Kim, Young-Jun
    • Journal of the Korea Organic Resources Recycling Association
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    • v.18 no.1
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    • pp.73-80
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    • 2010
  • Two nitrite oxidizing bacteria, NOB1 and NOB2, were isolated from anaerobic digester liquer of food wastewater and analyzed for their growth characteristics and the ability to oxidize nitrite under different temperature, pH, and DO( dissolved oxygen) concentrations. Both of the isolated strains have shown the best growth at pH 7.0 and at $35^{\circ}C$, and also shown higher growth rate with the increasing dissolved oxygen concentrations. As the factors to restrict the growth of these strains, parameters such as pH and DO were found to be effective ones, by increasing (up to 9.0) or decreasing pH (up to 5.0), or lowing DO below 1.0 ppm. Especially, the ability to oxidize nitrite in both strains was about 50% lower in below 1.0 ppm of DO than above of 1.0 ppm. NOB2 was found to be two times greater in both the growth rate and the nitrite-oxidizing ability than NOB1.

Comparison of Fuel-NOx Formation Characteristics in Conventional Air and Oxyfuel Combustion Conditions (일반 공기 및 순산소 연소 조건에서 Fuel-NOx 생성 특성의 비교)

  • Woo, Mino;Park, Kweon Ha;Choi, Byung Chul
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.37 no.5
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    • pp.481-488
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    • 2013
  • Nitric oxide ($NO_x$) formation characteristics in non-premixed diffusion flames of methane fuels have been investigated experimentally and numerically by adding 10% ammonia to the fuel stream, according to the variation of the oxygen ratio in the oxidizer with oxygen/carbon dioxide and oxygen/nitrogen mixtures. In an experiment of coflow jet flames, in the case of an oxidizer with oxygen/carbon dioxide, the $NO_x$ emission increased slightly as the oxygen ratio increased. On the other hand, in case of an oxygen/nitrogen oxidizer, the $NO_x$ emission was the maximum at an oxygen ratio of 0.7, and it exhibited non-monotonic behavior according to the oxygen ratio. Consequently, the $NO_x$ emission in the condition of oxyfuel combustion was overestimated as compared to that in the condition of conventional air combustion. To elucidate the characteristics of $NO_x$ formation for various oxidizer compositions, 1D and 2D numerical simulations have been conducted by adopting one kinetic mechanism. The result of 2D simulation for an oxidizer with oxygen/nitrogen well predicted the trend of experimentally measured $NO_x$ emissions.

The Influence of Some Soil-treated Herbicides on the Mineralization of Nitrogen Fertilizers I. In a flooded paddy soil (토양처리형 제초제가 질소비료의 무기화작용에 미치는 영향 I. 침수토양 조건)

  • Kim Moo Key
    • Korean journal of applied entomology
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    • v.15 no.4 s.29
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    • pp.205-214
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    • 1976
  • Effect of Butachlor(2-chloro-2, 6-diethyl N-(buthoxymethyl) acetanilide), Nitrofen(2,4-dichloro-4-nitrodiphenyl ether), Benthiocarb+Simetryne(s-(4-chlorobenzyl)-N, N-diethylthiocarbamate $7\%$+2-methylthio-4, 6-bis(ethylamino)-s-triazine $1.5\%)$, Propanil (3,4-dichloropropionanilide), and Perfluidone {1. 1. 1-trifluoro-N, N-(2-methyl-4-(phenylsulfonyl) Pheny1) methanesulfon amide} on urea hydrolysis and subsequent nitrification was investigated in a flooded soil incubated at $24\pm1^{\circ}C$ for 9 weeks. 1. Butachlor and Perfluidone at the rate of 1,440 and 1,200g, ai/10a, respectively, slightly inhibited the early stage of urea decomposition, and caused a slight decrease in the production of ammomium, which, however, was recovered readily. 2. Propanil at the rate of 2,800g, ai/10a imhibited the first stage of nitrification, and brought about a slight increase in the ammonium conentration and a decrease in the concentration of nitrite and nitrate. This inhibitive effect was a little more evident at higher concentration of applied nitrogen. The other herbicides caused no inhibition of urea decomposition and subsequent nitrification even at the highest rate of application. 3. pH and Eh of the soil were not significantly affected by the herbicides tested.

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NO Removal Characteristics in $N_2$ for a Dielectric Barrier Discharge Reactor with the Variation of a Discharge Gap (유전체 장벽 방전 반응기에서 방전 간극의 변화에 따른 질소 분위기하의 NO 제거 특성)

  • 차민석;이재옥;신완호;송영훈;김석준
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2000.11a
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    • pp.407-408
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    • 2000
  • 유전체 장벽 방전 반응기 (Dielectric Barrier Discharge (DBD) Reactor)를 이용한 비열 플라즈마(Non-thermal plasma) 공정에서 NO 제거 특성을 실험적으로 연구하였다. 질소 분위기에서 전자에 의한 NO 의 제거는 $N_2$ + e $\longrightarrow$ N + N + e 반응에 의한 질소의 전자충돌해리 (electron-impact dissociation)와 이 반응에 의하여 생성된 질소원자에 의한 NO 의 환원반응 N + NO $\longrightarrow$ $N_2$ + O 으로 설명될 수 있으며, 이로 인하여 $O_2$$H_2O$ 의 첨가에 따른 부산물(O, $O_3$, OH 등)에 의한 산화반응이 주로 일어나는 경우 (XO + NO $\longrightarrow$ X + NO$_2$) 와는 달리 NO 제거에 소모된 에너지를 평가하기에 용이한 장점이 있다(Penetrante et al., 1995). (중략)

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Development of Nitrogen Supply System for Launch Complex of KSLV-I (KSLV-I 발사대 질소 공급 시스템 개발)

  • Cho, Kie-Joo;Ahn, Kyu-Bok;Kim, Mun-Ki;Kang, Sun-Il;Ra, Seung-Ho;Oh, Seung-Hyub
    • Journal of the Korean Society of Propulsion Engineers
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    • v.15 no.2
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    • pp.68-73
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    • 2011
  • For the launch preparation of KSLV-I, gaseous nitrogen with various level of pressure and cryogenic liquid nitrogen are required. Nitrogen Supply System on launch complex has been developed to perform the production of high pressure gaseous nitrogen, the production of gaseous nitrogen with temperature of 273 ${\pm}$ 2K for protection purge of launch vehicle after loading of propellant and the supply of cryogenic liquid nitrogen for cooling of fuel (kerosene) and oxidizer (liquid oxygen). The operational instability of vaporizer mainly caused by its heat transfer characteristics which sensitively depends on the atmospheric conditions was removed by introducing parallel installation of two vaporizer and their switching operation. The developed Nitrogen Supply System carried out its function successfully in preparation of KSLV-I flight tests.

Development of Nitrogen Supply System for Launch Complex of KSLV-I (KSLV-I 발사대 질소공급시스템 개발)

  • Cho, Kie-Joo;Ahn, Kyu-Bok;Kim, Mun-Ki;Kang, Sun-Il;Ra, Seung-Ho;Oh, Seung-Hyub
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2010.11a
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    • pp.752-757
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    • 2010
  • For the launch preparation of KSLV-I, gaseous nitrogen with various level of pressure and cryogenic liquid nitrogen are required. Nitrogen Supply System on launch complex has been developed to perform the production of high pressure gaseous nitrogen, the production of gaseous nitrogen with temperature of $273{\pm}2K$ for protection purge of launch vehicle after loading of propellant and the supply of cryogenic liquid nitrogen for cooling of fuel (kerosene) and oxidizer (liquid oxygen). The operational instability of vaporizer mainly caused by its heat transfer characteristics which sensitively depends on the atmospheric conditions was removed by introducing parallel installation of two vaporizer and their switching operation. The developed Nitrogen Supply System carried out its function successfully in preparation of KSLV-I flight tests.

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