• Title/Summary/Keyword: P2X4

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The Rate of Superoxide Radical (${O_2}^-$.) Production in Normal Fenton's Reagent at Different pHs (펜톤반응에서 pH의 변화에 따른 superoxide radical (${O_2}^-$.)의 생성)

  • 김용수;공성호;김재호
    • Journal of Soil and Groundwater Environment
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    • v.7 no.2
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    • pp.73-81
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    • 2002
  • In normal Fenton's reagent, the reductive mechanism of carbon tetrachloride (CT) with superoxide radical (${O_2}^-$.) was observed and the rate of ${O_2}^-$. production was investigated as a function of $H_2O$$_2$ concentration and pH. As pH was increased, the rate of 1-hexanol degradation was rapidly decreased from 90% (at pH 3) to 5% (at pH 11). On the other hand, more degradation of carbon tetrachloride was observed at higher pH regimes indicating Fenton's reaction is an oxidant-reductant co-existing system at neutral pHs. The rate of $O_2^{-}$ . production was observed at different $H_2$$O_2$ concentrations and at different pHs. The rate increased from (45.3$\pm$7.8) x $10^{-6}$ M/s to (151.0$\pm$26.2) x $10^{-6}$ M/s ($294mM H_2$$O_2$) at pH 11: the rate 3150 increased from (22.1$\pm$3.8) x $10^{-6}$ M/s at pH 7 to (151.0$\pm$26.2) x $^10{-6}$ M/s at pH 11 with 294mM $H_2$$O_2$, These results showed that Fenton's reagent could be applied at wide pH regimes. Especially, carbon tetrachloride, which can not be easily adsorbed to soils and then can be dissolved into groundwater causing a cancer, could be efficiently treated by Fenton's reagent.reagent.

Isolation and Structure of $[Ph_3P(OH)]^+[ $N_3$]^-$ ($[Ph_3P(OH)]^+[ $N_3$^-$의 분리 및 구조)

  • Beom Jun Lee;Won Seok Han;Soon Won Lee
    • Korean Journal of Crystallography
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    • v.12 no.3
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    • pp.141-144
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    • 2001
  • From the reaction of Na[Ga(N₃)₄] with PPh₃, an ionic compound [Ph₃P(OH)]/sup +/[N₃]/sup -/ (1) was isolated. Compound 1 was characterized by spectroscopy (¹H-NMR, /sup 13C{¹H}-NMR, and IR) and X-ray diffraction. Crystallographic data for 1 : orthorhombic space group P2₁2₁2₁, a = 10.491 (4) Å, b=11.603(5)Å, c=13.149(5)Å, Z=4, R(wR₂)=0.0547(0.0978).

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Change in Solving Process According to Problem Type - Centered on Reaction toward Linear Equations of Seventh Grade Students - (문제 유형에 따른 풀이과정에서의 변화 - 중학교 1학년 학생들의 일차방정식에 대한 반응을 중심으로 -)

  • Seo, J.J.
    • Communications of Mathematical Education
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    • v.24 no.2
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    • pp.445-474
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    • 2010
  • The results of performing first survey after learning linear equation and second survey after 5 months to find out whether there is change in solving process while seventh grade students solve linear equations are as follows. First, as a result of performing McNemar Test in order to find out the correct answer ratio between first survey and second survey, it was shown as $p=.035^a$ in problem x+4=9 and $p=.012^a$ in problem $x+\frac{1}{4}=\frac{2}{3}$ of problem type A while being shown as $p=.012^a$ in problem x+3=8 and $p=.035^a$ in problem 5(x+2)=20 of problem type B. Second, while there were students not making errors in the second survey among students who made errors in the solving process of problem type A and B, students making errors in the second survey among the students who expressed the solving process correctly in the first survey were shown. Third, while there were students expressing the solving process of linear equation correctly for all problems (type A, type B and type C), there were students expressing several problems correctly and unable to do so for several problems. In conclusion, even if a student has expressed the solving process correctly on all problems, it would be difficult to foresee that the student is able to express properly in the solving process when another problem is given. According to the result of analyzing the reaction of students toward three problem types (type A, type B and type C), it is possible to determine whether a certain student is 'able' or 'unable' to express the solving process of linear equation by analyzing the problem solving process.

Evaluation of Fire Characteristics for Particle-board with Exfoliated Graphite Nanoplatelets Added (탄소재료의 적용 방법에 따른 파티클 보드의 연소 특성)

  • Seo, Hyun Jeong;Jo, Jeong Min;Hwang, Wuk;Lee, Min Chul
    • Journal of the Korean Society of Combustion
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    • v.22 no.4
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    • pp.1-8
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    • 2017
  • This study was conducted to evaluate the fire retardant performance of exfoliated graphite nanoplatelets (xGnP) applied for particleboard. This work measured heat release rate(HRR), total heat release(THR) and smoke production rate(SPR) of xGnP added particleboard, using cone calorimeter to assess its fire characteristics according to the KS F ISO 5660-1 standard code. Heat release rates of all specimens treated by xGnP were less than the $200kW/m^2$ for a total experiment period of five minutes. Heat release rates of the specimens coated with xGnP were lower than those of the specimens made by mixing wood particles with xGnP directly. Meanwhile, the total heat release rates of xGnP coated specimen maintained quite lower level than the uncoated so the xGnP coating were effective in improving the fire retardant performance of particleboard. However, the smoke emission peaking problem at the initial combustion period, which was caused by adding base coating materials, should be resolved for further satisfaction as a fire retardant materials.

A Study on Fecal Incontinence and Depression of Rural Women (농촌거주 여성의 변실금과 우울)

  • Kim, Chunmi;Lee, Hung Sa;Kim, Eun Man
    • Research in Community and Public Health Nursing
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    • v.25 no.3
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    • pp.198-206
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    • 2014
  • Purpose: The purposes of this study were to identify the prevalence and influencing factors of fecal incontinence, and to analyze the association between fecal incontinence and depression. Methods: The subjects of this study were 233 women living in rural areas, and data were collected using questionnaires from February 24 to May 30, 2012. Fecal incontinence was measured with the Continence Grading Score, and depression with the Geriatric Depression Scale. Collected data were analyzed using SPSS through $x^2$-test, Fisher's exact test, t-test and ANOVA. Results: Of the subjects, 16.7% had fecal incontinence. The prevalence of fecal incontinence was higher in older women ($x^2=23.55$, p<.001), those with vaginal delivery ($x^2=4.81$, p=.049), those with parity of 4 or more ($x^2=13.47$, p=.003), and those with urinary incontinence ($x^2=26.36$, p<.001). The level of depression was significantly higher in older women (F=19.27, p<.001), those with low academic qualification (F=18.17, p<.001), those with urinary incontinence (F=4.15, p=.043), and those with fecal incontinence (F=14.90, p<.001). Conclusion: These results suggest that there should be supports by public health care for fecal incontinence prevention and care programs in order to promote the physical and emotional health of rural women.

On The Completeness of $ F(X, Y)

  • Rhie, Gil-Seob;Sung, Yeoul-Ouk
    • Journal of the Korean Institute of Intelligent Systems
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    • v.4 no.2
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    • pp.9-12
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    • 1994
  • Let X, Y be normed linear spaces, and let p$_{1}$, p.sub 2/ be lower semi-continuous fuzzy norms on X, Y respectively, and have the bounded supports on X, Y respectively. In this paper, we prove that if Y is conplete, the set of all fuzzy continuous linear maps from X into Y is a fuzzy complete fuzzy normed linear space.

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Low Temperature Preparation and Photocatalytic Activity of TiO{2-x}Nx (TiO{2-x}Nx의 저온제조 및 광화학적 특성)

  • Jung, Dong-Woon
    • Journal of the Korean Chemical Society
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    • v.54 no.1
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    • pp.120-124
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    • 2010
  • $TiO_2$ and N-substituted $TiO_{2-x}N_x$ were synthesized by using precipitation method. $TiO_{2-x}N_x$ compound absorbed whole UV light as well as long wavelength of visible light (400 - 700 nm) because of the change of band gap from 3.2 eV to 1.77 eV. Results obtained revealed that $TiO_{2-x}N_x$ showed higher activity than pure $TiO_2$ or P-25 for visible-photocatalytic degradation of 1,4-dichlorobenzene.

Effect of Concentrate Level on Chewing Activities and Ruminal Characteristics in Daily Cows Fed Rice Straw , Corn Silage and Grass Hay (볏짚.옥수수사일레지.목건초 급여시 농후사료 급여수준이 젖소의 반추생리 및 저작 형태에 미치는 영향)

  • 윤상기;기광석;김현섭;권응기;강우성
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.15 no.3
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    • pp.207-214
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    • 1995
  • 'Ihis experiment was canied out to investigate the feed intake, chewing activities and ruminal characteristics by change in roughage intake and concentrate feeding amount with 15 Holstein cows. 1. DM intake of cow fed rice straw, corn silage and grass hay was 4.97, 5.47 and 5.60% of metabolic weight, respectively, and that by kg increase of concentrate was decreased by 0.330, 0.294 and 0.461 kg, respectively. 2. RVI of rice straw, com silage and grass hay was 98.3, 93.7 and 87.1 respectively, and correlations between RVIfl) and concentrate level@) were the following; $Y_1$(rice straw) = 99.4543 - 5.9759X + 0.0230$X^2$ This experiment was carried out to investigate the feed intake, chewing activities and ruminal characteristics by change in roughage intake and concentrate feeding amount with 15 Holstein cows. 1. DM intake of cow fed rice straw, corn silage and grass hay was 4.97, 5.47 and 5.60% of metabolic weight, respectively, and that by kg increase of concentrate was decreased by 0.330, 0.294 and 0.461 kg, respectively. 2. RVI of rice straw, com silage and grass hay was 98.3, 93.7 and 87.1 respectively, and correlations between RVI(Y) and concentrate level(X) were the following; $Y_1$(rice straw) = 99.4543 - 5.9759X + 0.0230$X^2$ $Y_2$(com silage) = 88.7601 - 2.9000X - 0.2111$X^2$ $Y_3$(grass hay) = 95.1515 - 6.3096X + 0.0873$X^2$ 3. Average ruminal pH in rice straw feeding group was the highest and correlations between ruminal pH(Y) and concentrate level(X) were the following; $Y_1$ = 7.0920 - 0.0309X - 0.0023$X^2$ $Y_2$ = 6.5000 - 0.0516X + 0.0002$X^2$ $Y_3$= 6.7666 - 0.0072X - 0.0044$X^2$ 4. Average ruminal $NH_3-N$ concentration in forage hay feeding group was the highest and correlations between ruminal $NH_3-N$ concentration(Y) and concentrate level(X) were the following. $Y_1$ = 3.3777 - 0.0587X + 0.0682$X^2$ $Y_2$ = 4.2765 + 0.5921X + 0.0181$X^2$ $Y_3$= 5.3634 - 0.4203X + 0.0223$X^2$ 5. Ruminal VFA wncentmtion in corn silage feeding group was the highest.

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Studies on Esterase of Pieris rapae L. II. Biochemical Properties and Immunological Studies (배추흰나비(Pieris rapae L.)의 esterase에 관한 연구 II. 생화학적 특성 및 면역학적 연구)

  • 박철호;김학열;여성문
    • The Korean Journal of Zoology
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    • v.33 no.3
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    • pp.337-345
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    • 1990
  • The properties of three esterases (E2, E6 and E11) which were previously purified from Pieris rapae L. were determined and physiological role of E6 was inferred using immunological methods. Based on inhibitor study, all of the purified esterases were found to be carboxylesterases (EC 3.1.1.1). The Km values for E2, E6 and E11 were determined to be 6.89 X 10-$^4$M. 3.19 $\times$ l0-$^4$M and 3.69 X 10-$^4$M, respectively. The molecular weights of E2, E6 and E11 were estimated to be 42 KD, 81 KD and 174 KD, respectively. The isoelectric points of E2, E6 and E11 were estimated to be pH 5.54, pH 5.89 and pH 6.50, respectively. The concentration of E6 during development was highest at the late 5th instar larval stage and that according to organs at the same stage was highest in midgut. These results suggest that E6 might be a hydrolase involved in the digestion of dietary lipids.

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G'p-SPACES FOR MAPS AND HOMOLOGY DECOMPOSITIONS

  • Yoon, Yeon Soo
    • Journal of the Chungcheong Mathematical Society
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    • v.28 no.4
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    • pp.603-614
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    • 2015
  • For a map $p:X{\rightarrow}A$, we define and study a concept of $G^{\prime}_p$-space for a map, which is a generalized one of a G'-space. Any G'-space is a $G^{\prime}_p$-space, but the converse does not hold. In fact, $CP^2$ is a $G^{\prime}_{\delta}$-space, but not a G'-space. It is shown that X is a $G^{\prime}_p$-space if and only if $G^n(X,p,A)=H^n(X)$ for all n. We also obtain some results about $G^{\prime}_p$-spaces and homology decompositions for spaces. As a corollary, we can obtain a dual result of Haslam's result about G-spaces and Postnikov systems.