• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
• /
• 제10권S_3호
• /
• pp.139-148
• /
• 2001

Heavy metals such as Cu, Ni, Cd, and Pb were chemically extract from the contaminated soils using the chelating agents, EDTA and DTPA. These chemical extraction have been focused on its applicability to a wide range of soils. Results of extractive efficiency for heavy metal follow the order : Cu-EDTA $\geq$ Ni-EDTA > Pb-EDTA > Cd-EDTA > Cu-DTPA> Pb-DTPA. This result is coincided with order of conditional formation constants(Kr) of metal-chelate agent. The second study involved the recovery of the metals and EDTA from complex solutions by an electromembrane process. The overall processes of regeneration, recovery, and reuse were evaluated. The electrochemical studies showed that copper could be chosen as an electrode to plate Cd, Cu, and Pb. At least 95% of 75 of EDTA and associated Cu or Pb could be recovered by the electromembrane process. Recovery of Cd by electodeposition was not possible with the copper electrode. The percent EDTA recovery is equal to the percentage of metal electroplated from the chelates.

• Biotechnology and Bioprocess Engineering:BBE
• /
• 제8권3호
• /
• pp.205-209
• /
• 2003

Solubilization of domestic household waste through Steam explosion with Subsequent ethanol production by the microbial saccharifitation and fermentation of the exploded product was studied. The effects of steam explosion on the changes of the density, viscosity, pH, and amounts of extractive components in artificial household waste were determined. The composition of artificial waste used was similar to leftover waste discharged from a typical home in Japan. Consecutive microbial saccharification and fermentation, and simultaneous microbial saccharification and fermentation of the Steam-exploded product were attempted using Aspergillus awamori, Trichoderma viride, and Saccharomyces cerevisiae; the ethanol yields of each process were compared. The highest ethanol yield was obtained with simultaneous microbial saccharification and fermentation of exploded product at a steam pressure of 2 MPa and a steaming time of 3 min.

• KSBB Journal
• /
• 제15권5호
• /
• pp.529-536
• /
• 2000

Results from experiments and mathematical modeling were compared for pervaporative butanol fermentation. The developed model includes expressions to predict characteristics of butanol fermentation, such as, microbial growth, solvent (butanol, acetone, and ethanol) formation and organic acid (acetate and butyrate) production. Butanol diffusivity was 1.15${\times}$10(sup)-7 ㎡/hr at 1.5 L/min-tubing of air flow rate using a pervaporative module. The model correlated well with experimental results (cell growth, glucose consumption and concentrations of solvents and organic acids) for batch fermentation with and without pervaporation. Larger surface area and thinner module tubing resulted in an increased glucose consumption and a decreased residual butanol concentration. Optimum membrane area and thickness were 0.34 ㎡ and 120 $\mu\textrm{m}$, respectively.

• Journal of the Korean Wood Science and Technology
• /
• 제26권4호
• /
• pp.71-77
• /
• 1998

To elucidate chemical structure of the wood extractive, wood meal of Larix leptolepis Gorden was extracted with 95% ethanol for 72 hours. The extract was fractionated with organic solvents such as n-hexane, chloroform, diethylether, and ethyl acetate. From the hexane somble fraction of the extractives, a new diterpene compound was isolated and identified as 6-acetoxymanool or 13-hydroxy-8(17), 14-labddienyl-6-acetate by IR, $^1H(^{13}C)$-NMR and Mass spectrometry.

• 미생물학회지
• /
• 제15권1호
• /
• pp.46-59
• /
• 1977

To screen biologically active components of the higher fungi of Korea, the carpophores of Auricularia polytricha, a well-known edible mushroom, were extracted with 0.14M NaCl solution. The extractive was successively fractionated by adding ammonium sulfate in various amounts, the respective precipitates being weparated by centrifugation, dialyzed and freeze-dried. When a dose of 60mg/kg of each was, i.p., injected into ICR mice, the fraction shich was precopitated at 20% (NH$_{4}$)$_{2}$SO$_{4}$ showed the highest toxicity, killing seven mice within two days. The fraction obtained at 40% (NH$_{4}$)$_{2}$SO$_{4}$ showed the second highest toxicity. The two fractions were named auratoxin I and II after the genus name. The symptoms of the intoxication were convulsion during the first 30 minutes after the injection, then sleeping within an hour, and tremor, lacrimation, nasal and ophthalmic bleeding, congestion and death in 24 hours. Particularly the spleen of the mice was fonud to be enlarged remarkably. The chemical analysis of the toxins showed that auratoxin I consisted of 4.4% protein and 84.5% polysaccharide and that auratoxin II 35.8% protein and 48.0% polysaccharide.

• 미생물학회지
• /
• 제22권4호
• /
• pp.223-228
• /
• 1984

To screen biologically active components of the higher fungi of Korea, the carpophores of Auricularia polytricha, a well-known edible mushroom, were extracted with 0.14M NaCl solution. The extractive was successively fractionated by adding ammonium sulfate in various amounts, the respective precipitates being weparated by centrifugation, dialyzed and freeze-dried. When a dose of 60mg/kg of each was, i.p., injected into ICR mice, the fraction shich was precopitated at 20% (NH/sub 4/)/sub 2/SO/sub 4/ showed the highest toxicity, killing seven mice within two days. The fraction obtained at 40% (NH/sub 4/)/sub 2/SO/sub 4/ showed the second highest toxicity. The two fractions were named auratoxin I and II after the genus name. The symptoms of the intoxication were convulsion during the first 30 minutes after the injection, then sleeping within an hour, and tremor, lacrimation, nasal and ophthalmic bleeding, congestion and death in 24 hours. Particularly the spleen of the mice was fonud to be enlarged remarkably. The chemical analysis of the toxins showed that auratoxin I consisted of 4.4% protein and 84.5% polysaccharide and that auratoxin II 35.8% protein and 48.0% polysaccharide.

• 한국컴퓨터정보학회논문지
• /
• 제24권7호
• /
• pp.31-37
• /
• 2019

Citation-based article summarization is to create a shortened text for an academic article, reflecting the content of citing sentences which contain other's thoughts about the target article to be summarized. To deal with the problem, this study introduces an extractive summarization method based on calculating a linear combination of various sentence salience scores, which represent the degrees to which a candidate sentence reflects the content of author's abstract text, reader's citing text, and the target article to be summarized. In the current study, salience scores are obtained by computing surface-level textual similarities. Experiments using CL-SciSumm datasets show that the proposed method parallels or outperforms the previous approaches in ROUGE evaluations against SciSumm-2017 human summaries and SciSumm-2016/2017 community summaries.

• 대한금속재료학회지
• /
• 제46권1호
• /
• pp.20-25
• /
• 2008

The ionic equilibira in mixed solutions of cuprous and cupric chloride were analyzed by considering chemical equilibria, mass and charge balance equations. The activity coefficients of solutes were calculated by using Bromley equation. Required thermodynamic constants and interaction parameters were evaluated from the data reported in the literature. The effect of NaCl and CuCl concentrations on the pH and potential of the mixed solutions was explained in terms of the variation in the concentration of solutes and in the activity of hydrogen ion. The calculated pH values of the mixed solutions agreed well with the measured values. However, the calculated values for the potential of the mixed solutions were lower than the measured values, indicating the necessity of considering the complex formation between cuprous and chloride ion, such as $Cu^2Cl{_4}^{2-}$ and $Cu_3Cl{_6}^{3-}$.

• 대한약학회:학술대회논문집
• /
• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
• /
• pp.218.2-218.2
• /
• 2003

An efficient method is described for the enantioseparation of urinary amino acids to determine their absolute configurations. It involves two-phase extractive ethoxycarbonylation in alkaline aqueous solution with subsequent extraction after acidification. The resulting derivatives of amino acids are converted to volatile diastereomeric esters or amides for the direct analysis by gas chromatography (GC) on achiral dual-columns with different polarities. The present method was applied to urine specimens from patients with inherited metabolic disorders. In this study, the usefulness for the chiral separation of diagnostic amino acids will be discussed.

• Journal of the Korean Wood Science and Technology
• /
• 제32권3호
• /
• pp.79-87
• /
• 2004

The objectives of this study were to select superior fungus for lignin degradation and to decolor dyes by selected fungus. Ligninolytic fungi were screened and isolated from decayed woods. Ten ligninolytic fungi were selected by ligninolytic enzyme activity on the PDA media containing rhemazol brilliant blue R, guaiacol and gallic acid. Their lignin degradation abilities were tested on the extractive-free wood powder of Quercus acutissima and Pinus densiflora. As a result, 8J-28 was selected as superior fungus for lignin degradation. Also, decolorization abilities of dyes were examined by shaking and static culture. And congo red, crystal violet, poly R-478, methylene blue used to investigate decolorization abilities of dyes. As a result, 8J-28 showed over 90% in decolorization of congo red, crystal violet, poly R-478.