• Title/Summary/Keyword: logP

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A New Analysis Method of the Consolidation Test Data for an Undisturbed Clay (불교란 점토 압밀시험 결과의 새로운 해석법)

  • 박종화;고우모또타쯔야
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.44 no.6
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    • pp.106-114
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    • 2002
  • In this study, the results of a series of consolidation test for undisturbed Ariake clay in Japan were analyzed by three methods, e-log p (e: void ratio, p: consolidation pressure), log e-log p and n-log p (n: porosity). Moreover, the characteristics of each analysis method were studied. For undisturbed Ariake clay, the log o-Log p and the n-log p relationships can be found as two groups of straight lines of different gradients, but both the elastic consolidation and plastic consolidation regions of e-log p relationship are expressed as a curve. In this paper, the porosity of consolidation yield n$\_$y/, consolidation yield stress p$\_$y/, and the gradient of the plastic consolidation region C$\_$p/ were represented by the log e-log p method, and n$\_$c/, P$\_$cn/ and C$\_$cn/ were represented by the n-log p method. The meaning and the relationships of each value were studied, and the interrelationships among compression indices i.e. C$\_$cn/, C$\_$p/ and C$\_$c/ are obtained from each analysis method as a function of initial porosity n$\_$0/.

QSAR Modeling of Toxicant Concentrations(EC50) on the Use of Bioluminescence Intensity of CMC Immobilized Photobacterium Phosphoreum (CMC 고정화 Photobacterium phosphoreum 의 생체발광량을 이용한 독성농도(EC50)의 QSAR 모델)

  • 이용제;허문석;이우창;전억한
    • KSBB Journal
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    • v.15 no.3
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    • pp.299-306
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    • 2000
  • Concern for the effects of toxic chemicals on the environment leads the search for better bioassay test organisms and test procedures. Photobacterium phosphoreum was used successfully as a test organism and the luminometer detection technique was an effective and simple method for determining the concentration of toxic chemicals. With EC50 a total of 14 chlorine substituted phenols benzenes and ethanes were used for the experiments. The test results showed that the toxicity to P. phosphoreum increased in the order of phenol > benzene > ethane and the toxicity also increased with the number of chlorine substitution. Quantitative structure activity relationship (QSARO) model can be used to predict EC50 to save time and endeavor. Correlation was well established with the QSAR parameters such as log P, log S and solvatochromic parameter(Vi/100 $\pi$, ${\beta}$m and am). The QSAR modeling was used with multi-regression analysis and mono-regression analysis. These analyses resulted in the following QSAR : $log EC_{50} =2.48 + 0.914 log S(n=9 R2=85.5% RE=0.378) log EC_{50}=0.35 - 4.48 Vi/100 + 2.84 \pi^* +9.46{\beta}m-4.48am (n =14 R2=98.2% RE=0.012) log EC_{50} =2.64 -1.66 log P(n=5, R2=98.8% RE=0.16) log EC_{50}=3.44 -1.09 log P(n=9 R2= 80.8% Re=0.207)$

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Reduction Factors of Pesticides with Different Physicochemical Properties under Washing and Cooking Conditions (물리화학적 특성이 다른 농약의 세척 및 조리방법에 의한 감소계수 산출)

  • You, Young-Hwa;Lee, Young-Sun;Kwon, Hoon-Jeong
    • Korean Journal of Food Science and Technology
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    • v.43 no.5
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    • pp.537-543
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    • 2011
  • The reduction factor of pesticides is getting more crucial these days. However, most studies have focused on the relationship between pesticides and commodities. This study was conducted to examine the pesticide reduction factor based on their physicochemical properties. Five pesticides were selected among 288 insecticides by considering the presence of an ionizable group, the log P, and boiling points. The correlation coefficients between log P and removal by tap water, 5% acetic acid, 20% ethanol, and 0.15% detergent were -0.835 (p<0.001), 0.336 (p=0.221), 0.659 (p<0.01), and -0.939 (p<0.001), respectively. Removal by blanching was affected by log P as it showed a positive correlation with a log P of 0.620 (p<0.05). Removal by frying showed a strong negative correlation with a log P of -0.913 (p<0.001). The results suggest that removing pesticides was affected largely by log P and by vapor pressure during cooking, whereas during washing, the matrix of the food also contributed to the reduction.

REMARKS ON SPECTRAL PROPERTIES OF p-HYPONORMAL AND LOG-HYPONORMAL OPERATORS

  • DUGGAL BHAGWATI P.;JEON, IN-HO
    • Bulletin of the Korean Mathematical Society
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    • v.42 no.3
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    • pp.543-554
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    • 2005
  • In this paper it is proved that for p-hyponormal or log-hyponormal operator A there exist an associated hyponormal operator T, a quasi-affinity X and an injection operator Y such that TX = XA and AY = YT. The operator A and T have the same spectral picture. We apply these results to give brief proofs of some well known spectral properties of p-hyponormal and log­hyponormal operators, amongst them that the spectrum is a con­tinuous function on these classes of operators.

Studies on Partition and Extraction Equilibria of Metal-Dithiocarbamate Complexes(II). Metal Complexes of Ammonium Pyrrolidine Dithiocarbamate (Dithiocarbamate 금속착물의 분배 및 추출평형(제2보). Ammonium Pyrrolidine Dithiocarbamate의 금속착물)

  • Lee, Jong-Sun;Choi, Jong-Moon;Choi, Hee-Seon;Kim, Young-Sang
    • Analytical Science and Technology
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    • v.8 no.3
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    • pp.321-334
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    • 1995
  • Basic studies for the effective extraction of ammonium pyrrolidine dithiocarbamate(APDC) complexes of Co(II), Ni(II) and Cu(II) into a solvent have been performed. The maximum distribution ratio was appeared (log D=1.3543) at pH 2.0 and the partition coefficient was 2.489 in the extraction of $4{\times}10^{-5}M$ APDC itself into chloroform. From the UV/visible spectra of metal-chelates in aqueous and organic solutions, the pH to form stable 1:2 metal-ligand complexes were Co(II):5.0, Ni(II):8.0 and Cu(II):8.0, respectively and only 1 minute was enough to be partitioned into the chloroform. Besides, the partition and extraction equilibria of the complexes were investigated by back-extracting $10.0{\mu}g/ml$ metal-chelates from the solvent into an aqueous solution beacuse of their slight solubilities in the aqueous solution. The distribution coefficients and extractabilities were as follows : at pH 6.5~8.5 of the aqueous solution, log D=2.834 : E(%)=99.9% for $Co(PDC)_2$, at pH 11, log D=5.699 E%=100 for $Ni( PDC)_2$, and at pH 6.0, log D=2.025 : E(%)=99.1% for $Cu(PDC)_2$. And the extraction and formation constants were log $K_{ex}=9.671$ : log ${\beta}_2=6.938$ for $Co(PDC)_2$, log $K_{ex}=9.646$ : log ${\beta}_2=7.071$ for $Ni( PDC)_2$, and log $K_{ex}=9.074$ : log ${\beta}_2=7.049$ for $Cu(PDC)_2$, respectively. From these results, an optimum extraction procedure can be constructed for the separative concentration of trace metallic ions, and the quantitative determination of them in advanced materials and environmental samples will be expected without any influence of sample matrixes.

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Selecting probability distribution of event mean concentrations from paddy fields (논으로부터 배출되는 유량가중평균 수질농도의 적정 확률분포 선정)

  • Jung, Jaewoon;Choi, Dongho;Yoon, Kwangsik
    • Journal of Environmental Impact Assessment
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    • v.23 no.4
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    • pp.285-295
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    • 2014
  • In this study, we analyzed probability distribution of EMCs (Event Mean Concentration) of COD, TOC, T-N, T-P and SS from rice paddy fields and compared the mean values of observed EMCs and the median values of estimated EMCs ($EMC_{50}$) through probability distribution. The field monitoring was conducted during a period of four crop-years (from May 1, 2008, to September 30. 2011) in a rice cultivation area located in Emda-myun, Hampyeong gun, Jeollanam-do, Korea. Four probability distributions such as Normal, Log-normal, Gamma, and Weibull distribution were used to fit values of EMCs from rice paddy fields. Our results showed that the applicable probability distributions were Normal, Log-normal, and Gamma distribution for COD, and Normal, Log- Normal, Gamma and Weibull distribution for T-N, and Log-normal, Gamma and Weibull distribution for T-P and TOC, and Log-normal and Gamma distribution for SS. Log-normal and Gamma distributions were acceptable for EMCs of all water quality constituents(COD, TOC, T-N, T-P and SS). Meanwhile, mean value of observed COD was similar to median value estimated by the gamma distribution, and TOC, T-N, T-P, and SS were similar to median value estimated by log-normal distribution, respectively.

SINGULARITY ORDER OF THE RIESZ-NÁGY-TAKÁCS FUNCTION

  • Baek, In-Soo
    • Communications of the Korean Mathematical Society
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    • v.30 no.1
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    • pp.7-21
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    • 2015
  • We give the characterization of H$\ddot{o}$lder differentiability points and non-differentiability points of the Riesz-N$\acute{a}$gy-Tak$\acute{a}$cs (RNT) singular function ${\Psi}_{a,p}$ satisfying ${\Psi}_{a,p}(a)=p$. It generalizes recent multifractal and metric number theoretical results associated with the RNT function. Besides, we classify the singular functions using the singularity order deduced from the H$\ddot{o}$lder derivative giving the information that a strictly increasing smooth function having a positive derivative Lebesgue almost everywhere has the singularity order 1 and the RNT function ${\Psi}_{a,p}$ has the singularity order $g(a,p)=\frac{a{\log}p+(1-a){\log}(1-p)}{a{\log}a+(1-a){\log}(1-a)}{\geq}1$.

Effect of Salicylate on Antibacterial Activity of Different Antibiotics

  • El-Naggar, Wael A.
    • Archives of Pharmacal Research
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    • v.15 no.1
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    • pp.99-103
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    • 1992
  • Susceptibility of Psudomonas aeruginosa, Staphylococcus aureus, and Bacillus subtilis to gentimicin and ceforaxime was affected by salicylaye. In presence of salicylaye (15 mM) and gentamicin (1.0 .mu.g/ml), log efficiency of plating (log E. O. P. s) for the tested bacteria were -1.24, -2.17 and -1.66 respectively. The activity of cefotaxime against Bacillus subtilis was reduced (log E. O. P. = 1.33). The highest potentiating effects of salicylaye were shown when using gentamicin against Staphylococcus aureus, cefotaxime against Ps. aeruginosa, log E. O. P.s were -3.0, and -2.4 respectively. On the other hand, no significant effects were detected with cefotaxime against Staphylococcus aureus (log E. O. P. = -0.04). No significant killing was shown in presence of gentamicin or salicylaye alone. There was no significant effect for salicylaye on MICs (By broth dilution) could be observed except in case of gentamicin against Staphyloccus aureus, which was reduced from 0.02 .mu.g/ml to 0.0012 .mu.g/ml. These results raise the concern that high concentrations of salicylaye in patients might interfere with antibiotic therapies.

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Approximation Algorithms for Maximizing the Overlap of Two Planar Convex Sets under Rigid Motions (두 평면 볼록집합의 겹치는 영역을 최대화하는 강체운동을 구하는 근사 알고리즘)

  • Park Chong-Dae;Shin Chan-Su;Ahn Hee-Kap;Cheong Otfried;Vigneron Antoine
    • Proceedings of the Korean Information Science Society Conference
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    • 2005.07a
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    • pp.901-903
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    • 2005
  • 본 논문에서는 평면 상에 두 볼록집합 P와 Q가 주어졌을 때, P를 강체운동 하에서 수평 이동 및 회전이동하여 Q와 겹치는 영역이 근사적으로 최대가 되는 알고리즘을 제시한다. 임의의 양의 상수 $\epsilon$이 주어졌을 때, 본 알고리즘은 가장 많이 겹치는 넓이의 $1-\epsilon$ 배를 보장하는 P의 강체운동을 $O((1/\epsilon)$ 번의 기하 질의 와 $O((1/{\epsilon}^2)log(1/$\epsilon)) 시간 내에 구할 수 있다. 특히 P와 Q가 볼록다각형 일 때, $O((1/\epsilon)log\;n+(1/{\epsilon}^2)log(1/\epsilon))$ 시간에 구한다. 만약 수평 이동만 사용할 경우는 $O((1/\epsilon)log\;n+(1/\epsilon)log(1/\epsilon))$ 시간에 구할 수 있다.

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Feasibility of Fibrous Solid Phase Extraction to Alkylphenols Analysis (섬유상 고상 추출물질을 이용한 알킬페놀 화합물 분석 가능성)

  • Jung, Yong Jun
    • Journal of Korean Society on Water Environment
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    • v.27 no.3
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    • pp.329-333
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    • 2011
  • p-phenylene-2,5-benzobisoxazole (PBO; Zylon$(R)$) fibers as an adsorbent were employed for solid phase extraction of aqueous alkylphenols. The removal ratios for 10 kinds of alkylphenols at initial concentration of $100{\mu}gL^{-1}$ were in the range of 16.8-96.3% and the removals increased with the increase of the phase ratio (fiber weight/solution volume). The plots of the logarithm of partition coefficient (log K) were correlated with the logarithm of the n-octanol/water partition coefficient (log P). The adsorbed alkylphenols were completely desorbed with the mixture of acetonitrile and dichloromethane.