• Title/Summary/Keyword: inhibition rate

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The Effects of Residual Al on Plankton Community after Dissolved Air Flotation (DAF) Application (가압부상 후 잔류 응집제가 플랑크톤 군집에 미치는 영향)

  • Kim, Ho-Sub;Gong, Dong-Su;Lee, Hyung-Jin;Shin, Jong-Kyu;Kang, Tae-Gu
    • Journal of Korean Society on Water Environment
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    • v.23 no.6
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    • pp.837-842
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    • 2007
  • This study was conducted to test the effect of residual Al on plankton community after dissolved air flotation (DAF) application. Growth rate of phytoplankton after DAF application ($0.37day^{-1}$) was about 2 times lower than that before DAF application ($0.70day^{-1}$). Under the condition of addition of nitrogen and phosphorus without light, growth rate phytoplankton in treatment without residual Al increased in difference with showing the negative growth rate in treatment with residual Al. Under the condition of light without addition of nutrient, growth rate of phytoplankton was no noticeable difference between the before and after DAF application. The relatively high settling rate (0.47 m/day) was observed in treatment after DAF application. Although the abundance of rotifer decreased, the abundance of copepod and cladoceran such as Daphnia galeata, Diaphanosoma sp. and Bosmina longirostris with relative higher grazing was no noticeable difference between the before and after DAF application. In the treatments before and after DAF application with zooplankton, growth rate of phytoplankton was $0.41{\pm}0.08day^{-1}$, $0.20{\pm}0.03day^{-1}$, respectively. This difference was in treatment after DAF application similar with those in treatments before and after DAF application without zooplankton. Those indicate that the filter-feeding effect of zooplankton on phytoplankton community may be not changed by residual Al after the DAF application. These results suggest that residual Al after DAF application be to improve water quality by inhibition of growth rate as well as increasing settling rate of phytoplankton.

Serological survey of Japanese encephalitis virus in domestic animals (축종별 일본뇌염바이러스에 대한 항체보유율 조사)

  • 이상준;정년기;송운재;장승익;하숙희;문병천;이필돈
    • Korean Journal of Veterinary Service
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    • v.26 no.1
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    • pp.11-18
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    • 2003
  • A total of 1,024 sera were collected from cattle(227), pigs(465), chickens(257) and dogs(75) raised or slaughtered in Daejeon metropolitan city from April to September 2002. Japanses encephalitis virus(JEV) antibodies in sera were detected by the haemagglutination inhibition test. The prevalence rates of JEV antibodies were 99.1 %, 54.0 %, 63.0 % and 98.7 % in cattle, pigs, chickens and dogs, respectively. In case of cattle and dogs, the monthly antibody-positive rates were as high as 85.7∼100.0 % and there were no differences among six months. In case of pigs, the monthly antibody-positive rate showed the lowest in April(6.4 %) and the highest in July(100.0 %) and it remained above 50 % during the summer-time. In case of chickens, the monthly antibody-positive rate was 100.0 % in July & August, 80.5 % in June, 40.0 % in May, 7.5 % in September and 5.0 % in April in order and there were distinct differences in seasons.

Inhibitory Effect of {Surfactant- MnO4-} Aggregation in KMnO4 Oxidation of Proline and Methionine: A Kinetic Study

  • Tripathi, Ritu;Upadhyay, Santosh K.
    • Journal of the Korean Chemical Society
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    • v.58 no.4
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    • pp.351-358
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    • 2014
  • Anionic (sodium lauryl sulphate, NaLS) cationic (cetyl ammonium bromide, CTAB) and non-ionic (Tween-80) surfactants have been found to inhibit the rate of oxiadation L-proline and L-methionine by alkaline $KMnO_4$. A first order dependence of rate of oxidation was observed with respect to $MnO_4{^-}$. The order of reaction in substrate and alkali was found to be fractional nearby 0.65 and 0.55 in Aminoacid and $OH^-$, respectively. An aggregation/association between $MnO_4{^-}$ and surfactant has been confirmed spectrophotometrically. A mechanism, involving kinetically inactive [$MnO_4{^-}$ surfactant] aggregate and consistent with kinetic data, has been proposed. The effect of surfactants has been discussed in terms of hydrophobic and electrostatic interactions.

전처리 공정에 따른 폐 신문지의 효소 가수분해 특성

  • Mun, Nam-Gyu;Lee, Jae-Hwan;Kim, Seong-Bae
    • 한국생물공학회:학술대회논문집
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    • 2000.04a
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    • pp.459-462
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    • 2000
  • The pretreatment of used newspaper for the enzymatic digestion preprocess was performed on a percolation reactor and a batch reactor. The test condition of percolation process was $170^{circ}C$, 60min, 1 mL/min, and 400psi, that of batch was $40^{circ}C$, 3hr. and latm Reaction solutions used in pretreatment process were aqueous ammonia, sulfuric acid, water, and hydrogen-peroxide as an oxidizing agent. As a result, the effect of pretreatment was similar to batch and percolation process, but the yield of enzymatic hydrolysis was higher in batch than percolation. This batch pretreatment enhanced enzymatic hydrolysis rate and increased glucose yield from about 15 to 20%. The inhibition factors influenced the rate of enzymatic hydrolysis was investigated, and the ink contented newspaper was the major factor.

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Role of CaO in the Sintering of 12Ce-TZP Ceramics (12Ce-TZP 세라믹스의 소결에서의 CaO의 역할)

  • 박정현;문성환;박한수
    • Journal of the Korean Ceramic Society
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    • v.29 no.4
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    • pp.265-272
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    • 1992
  • Role of CaO in the sintering of 12Ce-TZP ceramics was studied. The addition of small amounts of CaO increase the densification rate of 12Ce-TZP by altering lattice defect structure and the diffusion coefficient of the rate controlling species, namely cerium and zirconium cations. CaO also inhibits grain growth during sintering and allows the sintering process to proceed to theoretical density by maintaining a high diffusion flux of vacancies from the pores to the grain boundaries. The inhibition of grain growth is accomplished by the segregation of solute at the grain boundaries, causing a decrease in the grain boundary mobility. The segregation of calcium was revealed by AES study.

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Kinetics for the Growth of Alcaligenes eutrophus and the Biosynthesis of Poly-${\beta}$-hydroxybutyrate (Alcaligenes eutrophus 균주의 성장과 Ploy-${\beta}$-hydroxybutyrate 생합성에 대한 속도론)

  • Lee, Yong-Woo;Yoo, Young-Je
    • Microbiology and Biotechnology Letters
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    • v.19 no.2
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    • pp.186-192
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    • 1991
  • It is very important to have a good kinetic model which considers the effects of both ammonium and glucose for the control and optimization of the poly-${\beta}$-hydroxybutyrate (PHB) fermentation. A kinetic model for the growth of Alcaligenes eutrophus and the biosynthesis of PHB under both ammonium and glucose limitation was proposed. Growth rate of residual biomass was expressed as a function of concentrations of residual biomass, glucose and ammonium having glucose inhibition. PHB production rate was expressed as a function of concentrations of residual biomass, glucose, ammonium and PHB content having ammonium and product inhibitions. Novel approaches were made to estimate the parameters in the model equations which considered two limiting substrates. Model parameters were evaluated by graphical and simplex methods. The proposed kinetic model fitted the data very well.

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Evaluation of Sound-induced Affects based on Prefrontal Cortex Asymmetry and Heart Rate Variability (전전두엽의 비대칭성과 심장박동율변동성에 기초한 음향감성 평가)

  • 김원식;이지혜;조문재
    • Proceedings of the Korean Society for Emotion and Sensibility Conference
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    • 2001.11a
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    • pp.138-143
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    • 2001
  • 본 연구에서는 생환공간에서의 음향감성을 평가하기 위하여 긍정감성을 유발하는 음환경으로서 '명상음악'과 부정감성을 유발하는 음환경으로서 '헬리콥터소음'과 '마루가 삐거덕거리는 소음'을 제시하였을 때 행동활성화체계(BAS)와 행동억제체계(BIS)의 민감성이 서로 다른 집단들을 대상으로 전전두엽의(PFC) 비대칭성과 심장박동율변동성(HRV)을 분석하였다. 연구결과, 명상음악을 청취시에는 안정상태에 비하여 좌측전두엽이 더 활성화되고 HRV의 LF/HF는 감소된 반면에 소음환경에서는 우측전두엽이 더 활성화되고 LF/HF는 더 증가하였다.

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Effects of Reticuloendothelial Hyperfunction on Preservation of Lung (망내계기능 항진이 폐장보존에 미치는 영향)

  • 박동식
    • Journal of Chest Surgery
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    • v.7 no.2
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    • pp.145-152
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    • 1974
  • The effect of reticuloendothelial hyperfunction on hypothermic preservation of lung was studied in dogs. In order to evaluate the viability after hemodynamic_ load in preserved isolated lung, observations were made on the rate of increase in weight, degree of edema,compliance and surface activity of lung. The results obtained as follows: l. In the group of activating of the reticuloendothelial system by injection of sodium thiosulfate intravenously before pneumonectomy and infusion of naphthionine through the pulmonary artery before hypothermic preservation of isolated lung the limit of preservation was eight hours whereas four hours in non-treated control group. 2.Therefore the method of activating of the reticuloendothelial system before and after pulmonary resection seems effective in preserving for prolonging the period of preservation of lung by means of inhibition of pulmonary edema. 3. Pulmonary surface activity is expected to be valuable as a method in evaluation of the viability of preserved lung along with compliance and rate of increase in weight of lung.

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Hydroysis of Rice Straw with Trichoder-ma viride TO4 Cellulase

  • Lee, Mun-Ho;Yong, Pack-Moo
    • Proceedings of the Korean Society for Applied Microbiology Conference
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    • 1978.10a
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    • pp.208.2-208
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    • 1978
  • Rice Straw was delignified by autoclaving with 1% NaOH solution at $121^{\circ}C$ for one hour and was disintegrated by a Wiley mill to 60 mesh. This substrate was saccharified with cellulase produced by Trichoderma viride T04 in solid culture me-dium. The rate and extent of hydrolysis were both increased when high enzyme concentration and low substrate concentration were employed. The original cellulose was treated with 0.19 FPA unit for three hours and followed by the second treatment for the same period with the same concentration of enzyme after washing. By doing this the hydrolysis rate at the second stage could increase four folds of that unwashed. The same experiment with 0.32 FPA unit yielded two folds suggesting an end-product inhibition on the recaction system. The extent of hydrolysis however, could not be in-creased by this process.

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Influence of Oxytocin on the Renal Function of the Chicken (닭의 신장기능(腎臟機能)에 미치는 Oxytocin의 영향(影響))

  • Ko, Suk-Tai
    • Journal of Pharmaceutical Investigation
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    • v.1 no.1
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    • pp.34-46
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    • 1971
  • The existence of oxytocin in the pituitary gland of chicken has been ascertained, but its physiological roles are still obscure. In the study the action of oxytocin on renal function of the chicken was investigated during water diuresis, utilizing clearance and the Sperber technique. The results obtained are summarized as follows: Oxytocin, like in many species of mammals, elicited a profound diuretic response in the chicken. Urine flow, excretion of electrolytes, as well as glomerular filteration rate increased, with intravenous infusion of $3{\sim}10\;m{\mu}/kg/min$. Oxtocin, infused into the renal portal circulation via hindleg vein in a dose of $3{\sim}13\;m{\mu}/kg/min$. elicited marked increase in urine flow, glomerular filteration rate and sodium excreted in the urine. The diuretic effect was more pronounced in the infused side. It is suggested that diuretic response to oxytocin in the chicken results from dual action of oxytocin: increase of GFR and inhibition of sodium reabsorption on the renal tubule. The possibility that oxytocin might act through some endogenous substances could be ruled out.

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