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레이저 유도 형광법(LIF)을 이용한 버너 화염의 NO 농도측정에 관한 연구 (A Study on Measurement of NO Concentrations in Burner Flames by LIF)

  • 박경석;김성욱
    • 한국분무공학회지
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    • 제7권4호
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    • pp.42-49
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    • 2002
  • In this study, quantitative measurement of nitric oxide concentration distributions were investigated in the laminar CH4/O2/N2 premixed flame by laser-induced fluorescence (LIF). The NO A-X (0,0) vibrational band around 226nm was excited using a XeCl excimer-pumped dye laser. Selecting an appropriate NO transition minimizes interference from Rayleigh scattering and O2 fluorescence. The measurements were taken in CH4/O2/N2 premixed flame with equivalence ratios varying from $1.0{\sim}1.6$, and a fixed flowrate of 5slpm. NO was found to produce primarily between an inner premixed and an outer nonpremixed flame front, and total NO concentration is raised when equivalence ratios increase. These results suggest that prompt NO is likely to contribute to NO formation in CH4/O2/N2 premixed flame. Furthermore, this trend was well matched with previous works.

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NH3 SNCR을 이용한 NOx 제거 : 실험 및 모사 (NH3-based SNCR of NOx : Experimental and Simulation)

  • 차진선;박성훈;전종기;박영권
    • 공업화학
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    • 제22권4호
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    • pp.433-438
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    • 2011
  • 본 연구에서는 SNCR 공정에서 온도, NSR, 산소 농도가 질소산화물 제거 효율에 미치는 영향을 실험과 CHEMKIN-II 프로그램을 사용하여 수치적으로 조사하였다. 산소가 없는 조건에서 NO 제거 효율은 반응기 온도에 따라 증가하였다. 반면 산소농도가 4%일 때, NO 제거 효율은 $900{\sim}950^{\circ}C$에서 최대를 나타내었다. 산소의 존재는 저온에서 NO 제거를 증가시키는 것으로 나타났다. 산소농도와 무관하게 NO 제거 효율은 NSR에 따라 증가하였다. CHEMKIN-II에 의해 예측된 NO 제거 효율의 온도와 NSR-의존성은 실험결과와 유사하였다.

Serum Biochemical Values during Antler Growth in Sika Deer (Cervus nippon)

  • Jeon, B.T.;Kang, S.K.;Lee, S.M.;Hong, S.K.;Moon, S.H.
    • Asian-Australasian Journal of Animal Sciences
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    • 제20권5호
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    • pp.748-753
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    • 2007
  • Serum biochemical values were measured in blood samples collected from 8 fasted stags from both jugular and femoral veins at 18-day intervals during antler growth. Samples were analyzed for blood substrate, enzyme activity values, minerals and electrolyte. There were no significant differences in total protein, albumin, urea, creatinine, triglyceride, glucose or cholesterol concentration between veins or sampling dates. However, total-bilirubin concentration in the jugular vein on the casting date was three times higher than on the other sampling dates (p<0.05). There were no significant differences in alkaline phosphatase, aspartate aminotransferase, and alanine aminotransferase with progressing antler growth. The highest level of alkaline phosphatase concentration was on day 55 after casting. There were no significant differences in inorganic phosphorus, sodium and chloride concentration between jugular and femoral samples. Calcium concentration was significantly higher in the femoral vein on the cutting date (55 day) than in the jugular vein (p<0.05). There were few changes in serum biochemical values. However, some electrolytes and minerals had differences during antler growth. It is suggested that despite such a big event as antler growth, blood biochemical values are not variable if feeding conditions are consistently maintained as was the case in this study.

서울시 일부 음식점 종업원의 간접흡연 노출량 측정 (Environmental Tobacco Smoke Exposure of Workers at Restaurants in Seoul Metropolitan City)

  • 고영림;양원호;정문호
    • 한국환경보건학회지
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    • 제28권2호
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    • pp.173-182
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    • 2002
  • Exposure to environmental tobacco smoke(ETS) increases the risk of lung cancer and other diverse health effect for nonsmokers. Health risk assessment of nonsmokers related to ETS exposure requires large and exact data of ETS exposure to nonsmokers. This study presented the data of ETS exposure to workers at three category of restaurants(Korean restaurant, coffee shop, wine shop) in Seoul. Markers of ETS exposure measured in this study were area and personal NO$_2$, area and urine nicotine, area respiratory suspended particulate(RSP) and urine cotinine. The mean concentration of RSP and nicotine of all restaurant indoor samples was 177.8$\mu\textrm{g}$/㎥(range:75.3~317.0$\mu\textrm{g}$/㎥) and 7.8$\mu\textrm{g}$/㎥(range:0~57.3$\mu\textrm{g}$/㎥). The mean concentration of urine cotinine measured for the biomarker of ETS exposure was 77.3ng/mL(range:17.3~174.6ng/mL). In all measurements, the concentration of ETS markers at the wine shop was higher than those at other restaurants. The correlation coefficient among the ETS markers measured in the study was significant between area RSP and nicotine concentration and between area NO$_2$and nicotine concentration.

폐경후 여성에서 비타민 K와 골대사와의 상관성에 관한 연구 (The Study of Correlation between Serum Vitamin K Concentration and Bone Metabolism in Postmenopausal Women)

  • 홍주영
    • Journal of Nutrition and Health
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    • 제32권3호
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    • pp.287-295
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    • 1999
  • This study was conducted to observe the effect of vitamin K on bone metabolism in postmenopausal women. Twenty-four healthy postmenopausal women recruited for this one-month, double-blind controlled study. Before and after daily administration of 1.0mg of phylloquinone the levels of serum vitamin K, osteocalcin, under-carboxylated osteocalcin, and urinary deoxy-phyidinoline were measured. The serum vitamin K concentration of Koran women as well as the average dietary intake of vitamin K was shown to be higher than the average levels of foreign women. However, no correlation between serum vitamin K concentration and vitamin K intake was found. Also, serum vitamin K concentration showed no special correlation with either bone mineral density or bone turnover markers in the study group. However, women with low serum vitamin K concentration(vitamin K-low group)had lower bone mineral density levels. After supplementation with 1.0mg/day of vitamin K, there were no changes in the levels of serum vitamin K, osteocalcin, ucOC, or u-DPD. Vitamin K supplementation did not seem to have any positive effects on bone metabolism through carboxylation. It can, however, be expected that vitamin K supplementation has a positive effect on bone metabolism in postmenopausal women with especially low serum vitamin K concentrations.

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주의·집중훈련 프로그램의 두 가지 과제수행에 따른 뇌파 변화 (Changes in EEG According to Attention and Concentration Training Programs with Performed Difference Tasks)

  • 채정병
    • PNF and Movement
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    • 제12권2호
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    • pp.97-106
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    • 2014
  • Purpose: The purpose of this study was to investigate changes in EEG through attention. Concentration training and performing tasks are important factors in the improvement of motor learning ability. Methods: In the experiment, 22 healthy people were divided into two groups: the trail making test (TMT) group and the computerized neurocognitive function test (CNT) group. A one-way Neuro Harmony M test to see whether there was a significant difference among the groups. Results: The TMT group showed a significant increase in ${\alpha}$ wave, ${\alpha}$ wave sequence, and ${\beta}$ wave sequence; however, there were no significant differences in SMR wave, SMR wave sequence, and ${\beta}$ wave. The CNT group showed increases in ${\alpha}$ wave, ${\alpha}$ wave sequence, SMR wave, SMR wave sequence, and ${\beta}$ wave sequence; however, there was no significant difference in ${\beta}$ wave. In EEGs before and after two performance tasks were changed, there were significant differences in ${\beta}$ wave, SMR wave, SMR wave sequence; however, there were no significant differences in ${\alpha}$ wave sequence, ${\beta}$ wave, and ${\beta}$ wave sequence. Conclusion: Attention training and concentration training offer feedback and repetition for constant stimulus and response. Moreover, attention training and concentration training can contribute to new studies and motivation by developing fast sensory and motor skills through acceptable visual and auditory stimulation.

대기 중 NO2 측정의 불확도 평가 (Evaluation of Uncertainties in the Measurement of Ambient NO2 Level)

  • 이진홍;임종명;우진춘
    • 한국대기환경학회지
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    • 제18권5호
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    • pp.355-362
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    • 2002
  • There has been relatively a few studies that focused on evaluation of uncertainty for standard methods by which criteria pollutants are analyzed in ambient air. Especially, uncertainty evaluation has not been made yet for sampling and analysis of airborne NO$_2$. Ambient NO$_2$ has been thought to be a major criteria pollutant worldwide because of the potential of ozone formation as well as of its own toxicity. In this study, we tried to assess uncertainties associated with the every step of sampling and of analytical procedure of Griess-Saltzman method. Quality assurance (QA) and quality control (QC) were also emphasized with the uncertainty characterization. The use of Griess-Saltzman method for ambient NO$_2$ analysis showed very uniform daily concentration distribution with the mean of 10.8 ppb and the standard deviation of 1.08ppb during the sampling period. However, seven daily samples collected at the same sampling time and place exhibited highly different concentration distribution. Therefore, we evaluated uncertainties associated with sampling and analysis through the precise application of ISO Guide. Estimates of expanded uncertainties for a total of 62 samples fell in a relatively broad range of 5.17% to 11.85%. On the other hand. the expanded uncertainties were smaller for the high concentration range of greater than 15ppb.

Inhibitory Activity of Chinese Medicinal Plants on Nitric Oxide Synthesis in Lipopolysaccharide -Activated Macrophages

  • Ryu, Jae-Ha;Ahn, Han-Na;Lee, Hwa-Jin;Feng, Li;Qun, Wen-He;Han, Yong-Nam;Han, Byung-Hoon
    • Biomolecules & Therapeutics
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    • 제9권3호
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    • pp.183-187
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    • 2001
  • Nitric oxide (NO) produced in large amounts by the inducible nitric oxide synthase (iNOS) is known to be responsible for the vasodilation and hypotension observed in septic shock and inflammation. The inhibitors of iNOS, thus, may be useful candidate for the treatment of inflammatory diseases accompanied by the overproduction of NO. We prepared alcoholic extracts of Chinese medicinal plants and screened their inhibitory activity against NO production in lipopolysaccharide (LPS)-activated macrophages. Among the 80 kinds of extracts of herbal drugs, 15 extracts showed potent inhibitory activity of NO production above 80% at the concentration o$50\mu\textrm{g}/ml$. These potent extracts showed dose dependent inhibition of NO production of LPS-activated macrophages at the concentration of 50, 30,$10\mu\textrm{g}/ml$. Especially, Rhus chinensis, Senecio scandens and Wikstroemia indica showed most potent inhibition above 50% at the concentration of $10\mu\textrm{g}/ml$. These plants are promising candidates for the study of the activity-guided purification of active compounds and would be useful for the treatment of inflammatory diseases and endotoxemia accompanying the overproduction of NO.

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Effects of Essential Oils Supplementation on Growth Performance, IgG Concentration and Fecal Noxious Gas Concentration of Weaned Pigs

  • Cho, J.H.;Chen, Y.J.;Min, B.J.;Kim, H.J.;Kwon, O.S.;Shon, K.S.;Kim, I.H.;Kim, S.J.;Asamer, A.
    • Asian-Australasian Journal of Animal Sciences
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    • 제19권1호
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    • pp.80-85
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    • 2006
  • Ninety six crossbred pigs (Landrace${\times}$Yorkshire${\times}$Duroc) were used to determine the effects of essential oils (Fresta F $Conc^{(R)}$) supplementation on growth performance, immune response and fecal noxious gas of weaned pigs. Treatments were 1) NC (negative control; basal diet without antibiotics), 2) PC [positive control; basal diet+CSP (CTC+Sulfathiazole+Penicillin) 0.1%], 3) NCF (basal diet+Fresta F $Conc^{(R)}$ 0.03%) and 4) PCF [basal diet+CSP (CTC+Sulfathiazole+Penicillin) 0.1%+Fresta F $Conc^{(R)}$ 0.02%]. From d 0 to 14, ADFI was increased in pigs fed PCF diet (p<0.05). From d 14 to 28, pigs fed PCF diet had greater ADG and ADFI than pigs fed NC diet (p<0.05). From d 28 to 49, ADG and ADFI in pigs fed PCF diet were higher than in pigs fed NC diet (p<0.05). Through the entire experimental period, ADG and ADFI in pigs fed PCF diet were the highest compared to pigs fed NC and PC diets (p<0.05). There was no significant difference in fecal consistency score among the treatments (p>0.05). No statistical differences (p>0.05) were found in red blood cells (RBC) counts, white blood cells (WBC) counts, lymphocyte counts, total protein and albumin. Serum IgG concentration of PCF treatment was greater than that of other treatments (p<0.05). From d 0 to 14, there was no significant difference in digestibility of dry matter and nitrogen among the treatments (p>0.05). From d 14 to 28, digestibility of dry matter in pigs fed PC, NCF and PCF diets was higher than that of pigs fed NC diet (p<0.05) and treatments with added essential oils were higher than other diets on digestibility of nitrogen (p<0.05). Also, from d 28 to 49, digestibility of nitrogen in pigs fed PCF diet was the highest among others (p<0.05). On d 14 and 28, no statistical differences (p>0.05) were found in volatile fatty acid (VFA), ammonia nitrogen ($NH_3$-N) and hydrogen sulfide ($H_2S$) concentrations among treatments. On d 49, there was no significant difference in VFA concentration among the treatments (p>0.05). $NH_3$-N concentration in pigs fed PCF diet was lower than in pigs fed other diets (p<0.05). $H_2S$ concentration in pigs fed diets with added essential oils was lower than others. In conclusion, the results suggest that the dietary addition of essential oils and antibiotics into diets for weanling pigs improved growth performance, IgG concentration and nitrogen digestibility and decreased noxious gas concentration. Essential oils can be used to partly replace antibiotics in diets for weaned pigs without negative affects on growth performance.

Biological nitrogen removal of ammonium-rich industrial wastewater by suspended bacterial growth

  • 임준택;성세현;황석환
    • 한국생물공학회:학술대회논문집
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    • 한국생물공학회 2002년도 생물공학의 동향 (X)
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    • pp.399-402
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    • 2002
  • Industrial wastewater with high ammonium concentration was treated in batch biological systems which was a modified Ludzack- Ettinger process. Up to 78% conversion of $NH_4\;^+-N$ to $NO_x\;^--N$ was achieved in batch culture condition. Under anoxic condition with methanol as the carbon source, the denitrifiers decreased $NO_x\;^--N$ concentration from 608 mg/L to 5.6 mg/L in 22 d. As well as anoxic denitrification of $NO_x\;^-$ to $N_2$, dissimilatory nitrate reduction to ammonium also occurred under the condition as respiratory denitrification.

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