• Fibers and Polymers
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• v.3 no.2
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• pp.68-73
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• 2002

In this study, a new type of Aliquat 336/PVC membrane has been made for extraction experiments. This new membrane is capable of holding more Aliquat 336 than previously developed extraction membranes, hence overcoming a major problem that has confronted many researchers for a long time. The new membrane has been used try investigate the rate of extraction fur the Cd(II) ion in 2.0 M HCI solution and the effect of membrane thickness on the rate of extraction. The experimental results have shown this new membrane has a promising future in relevant industrial applications. A new method is also used in this study to qualitatively identify the oily substance on the surface of membrane after the extraction experiment was completed. This oily substance has been found to be Aliquat 336.

• Journal of the Korean Chemical Society
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• v.5 no.1
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• pp.15-17
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• 1961

A ninhydrin positive substance(formed during germination of Mung Bean) which on a 2-dimensional chromatography(BuOH-HAc, and$ PhOH-NH_2$ gave a spot above glutamic acid was isolated by cutting out the appropriate spot on the paper and extracting the paper with water. Hydrolysis of this substance with $2N H_2SO_4\;or\;3N\;HCl\;at\;120^{\circ}C$ for 15 hours gave the spot of mainly glutamic acid, alanine and very faint of glycine and cysteine on a paper chromatography. It is suggested that the reaction of ${\gamma}$-glutamyl-cysteinecyl-glycine + L-alanine in the presence of ${\gamma}$-glutamyle transferase ${\rightarrow}$ ${\gamma}$-glutamyl-alanine + cysteinyl-glycine, takes place in germinated Mung Bean.

• Bulletin of the Korean Chemical Society
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• v.34 no.2
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• pp.531-538
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• 2013

A mass balance method established in this laboratory was applied to determine the purity of an endosulfan-II pure substance. Gas chromatography-flame ionization detector (GC-FID) was used to measure organic impurities. Total of 10 structurally related organic impurities were detected by GC-FID in the material. Water content was determined to be 0.187% by Karl-Fischer (K-F) coulometry with an oven-drying method. Non-volatile residual impurities was not detected by Thermal gravimetric analysis (TGA) within the detection limit of 0.04% (0.7 ${\mu}g$ in absolute amount). Residual solvents within the substance were determined to be 0.007% in the Endosulfan-II pure substance by running GC-FID after dissolving it with two solvents. The purity of the endosulfan-II was finally assigned to be ($99.17{\pm}0.14$)%. Details of the mass balance method including interpretation and evaluating uncertainties of results from each individual methods and the finally assayed purity were also described.

• Journal of environmental and Sanitary engineering
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• v.10 no.1
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• pp.132-141
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• 1995

The objectives of this study was to find the effect of zinc salt treated with coconut activated carbon and the effect of humic substance. The bottle- Point technique was used in determining the Freundlich isotherm equation. The adsorptive capacity of granular activated carbon was reduced when humic substance are present. Coconut activated carbon was coated with 0.0001 N zinc chloride decreased the BET surface area but increased the adsorptive capacity more than coconut activated carbon not coated with zinc chloride. The adsorptive capacity of TCE in coconut activated carbon coated with higher concentration of zinc chloride was reduced but increased in the solution containing humic substance when the coconut activated carbon was coated with 0.01 N- zinc chloride. The zinc salt coated with coconut activated carbon did not Increase the adsorptive velocity of coconut activated carbon.

• Journal of Microbiology and Biotechnology
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• v.17 no.7
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• pp.1217-1220
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• 2007

The saprophytic fungus Ulocladium atrum Preuss is a promising biological control agent for Botrytis cinerea in greenhouse- and field-grown crops. However, despite its known potent antifungal activity, no antifungal substance has yet been reported. In an effort to characterize the antifungal substance from U. atrum, we isolated an antibiotic peptide. Based on extensive spectroscopic analyses, its structure was established as a cyclopeptolide with a high portion of N-methylated amino acids, and its $^1H$ and $^{13}C$ chemical shifts were completely assigned based on extensive 1D and 2D NMR experiments. Compound 1 exhibited potent antifungal activity against the plant pathogenic fungus Botrytis cinerea and moderate activity against Alternaria alternate and Magnaporthe grisea.

• Journal of the Korean Chemical Society
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• v.56 no.6
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• pp.739-750
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• 2012

The purpose of this study is to analyze the cognitive demands level of the description about 'pure substance and mixture compound', 'ionic compound', 'molecule' on the 'science2' textbooks by the 2007 revised curriculum. The three types of Curriculum Analysis Taxonomy have been used to analyze the cognitive demands level of those contents on the 6 kinds of 'science2' textbooks. The first, the cognitive demand level about 'pure substance and mixture compound' on many textbooks is a late concrete operational stage because of class inclusion and hierarchical classification. And the descriptions as 'pure substance is conserved even when mixed with other pure substance' is a early formal operational stage. The second, the cognitive demand level about 'ionic compound' and 'molecule' is a early formal operational stage, because of "Formal modeling is the indirect interpretation of reality by deductive comparison from a postulated system with its own rules" and "Atoms have a structure". The third, the terms as 'ionic bonding', 'ionic compound', 'chemical formula', 'covalent bonding', 'covalent compound', and 'molecular formula' have been used on many 'science2' textbooks. Those terms would be used later on 'chemistry I' and 'chemistry II' in senior high school but not even 'science3' and 'science'.

• Korean Journal of Bronchoesophagology
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• v.2 no.1
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• pp.97-102
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• 1996

The larynx has three major functions such as protective reflex, respiration and phonation, and is richly innervated by sensory, sympathetic and parasympathetic nerves. The sensory innervation of the laryngeal mucosa, which is involved in the perception of pain, mechanical and chemical irritation, prtects the airway via various laryngeal reflexes. We studied the distribution of Substance P (SP) and Calcitonin Gene-Related Peptide (CGRP) sensory fibers in the rat's larynx using the immuno-histochemical methods. Many SP and CGRP immunoreactive fibers were found in all regions of the laryngeal mucosa except the vocal cords. SP immunoreactive fibers showed a very similar distribution to the CGRP fibers in the epithelium and submucosa. But SP immunoreactive fibers were sparser than CGRP immunoreactive fibers in distribution density. Both reactive fibers were denser in the supraglottic region than subglottic region. Especially, intraepithelial fibers displayed the densest innervation to the laryngeal surface of the epiglottis. h the subepithelium, SP and CGRP immunoreactive fibers were distributed along the wall of vessels and around the glands. The present results suggest that the regional distribution of SP and CGRP immunoreactivity may be responsible for the protective reflex function of the laryngeal inlet.

• Preventive Nutrition and Food Science
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• v.6 no.4
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• pp.230-234
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• 2001

The extract of Ulmus davidiana var. japonica cortex has known as natural anti-inflammatory substance in East Asia. For the identification of antimicrobial substance, it was extracted by using methanol and fractionated by using different organic solvents. The fraction of butanol was represented the highest antimicrobial activities. Therefore, the butanol fraction was purified and identified the chemical structure by $^1$H and $^{13}$ C-NMR spectra, FT-IR and EI/MS spectroscopies. The isolated antimicrobial substance was identified as cis-2-[3,4-dihydroxy phenyl]-3,4-dihydro-2H-1-benzopyran-3,5,7-triol, which has commonly known as (-)epicatechin. Its minimum inhibitory concentrations (MICs) against Staphylococcus aureus and Listeria monocytogenes were shown as 100 $\mu\textrm{g}$/mL, respectively.

• Resources Recycling
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• v.20 no.5
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• pp.58-63
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• 2011

pH control-precipitation method is used for recovery of EDTA from waste fluid of archeological waterlogged wood conservation treatment. EDTA has been used for eliminating of blacken effect in archeological waterlogged wood which was buried in the ground for long period of time. The black substance is generated by Fe$^{3+}$ in the soil reacted with tannin in the archeological waterlogged wood. In order to remove the black substance in archeological waterlogged wood, EDTA was used. The black substance is eliminated from wood as Fe-EDTA complex are formed, and EDTA is separated and precipitated from Fe-EDTA complexes at pH 2.68 or less. The result of analysis of the precipitated products and the commercial EDTA by FT-IR and FE-SEM showed that precipitated product by pH adjusted was not a type of Fe-EDTA complex, but pure EDTA. In this study, Fe$^{3+}$ from waste fluid of EDTA can be separated by HCl added. EDTA can be recycled by using the method of precipitation of EDTA in a strong acid.

• YAKHAK HOEJI
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• v.33 no.3
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• pp.203-205
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• 1989

A method is presented for calculating the $^{13}C$ chemical shifts produced in liquid solution by referenced relative to RF frequency. The method is useful to get the real variations of chemical shifts in magnetic field by eliminating the affects of the variation of a reference substance.