• Membrane Journal
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• v.26 no.5
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• pp.381-390
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• 2016

In this study, the natural mordenite (MOR) zeolite seeds were used for the synthesis of high purity mordenite crystals. The effect of seed concentration and crystallization time on the phase purity and surface morphology of MOR crystals has also been reported. The diffraction, elemental and scanning analysis of MOR zeolite particles obtained from 100 g hydrothermal solution batch containing 3 g natural seed, hydrothermally treated at $140^{\circ}C$ for 72 h reveal the high phase-purity of as-synthesized sample having crystals of uniform size ($1-2{\mu}m$). Moreover, high seed concentration leads to the production of mesoporous MOR particles composed of needle shape primary nano crystallites. The gases adsorption performances of as-synthesized MOR particle were carried out at $25^{\circ}C$ and 0-1 bar. Surprisingly, MOR particles show good adsorption potential for $CO_2$ (97.19 mg/g) compared to other gases. Thus it confirms that high purity MOR particles can be synthesized without using any organic template which gives an advantage of separation performance at lower price.

• Korean Chemical Engineering Research
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• v.43 no.3
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• pp.352-359
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• 2005

This work has studied the changes of pH in both of anodic and cathodic chambers of a divided cell due to the electrolytic split of water during the ammonia decomposition to nitrogen, and has studied the continuous decomposition characteristics of ammonia in a multi-cell stacked electrolyzer. The electrolytic decomposition of ammonia was much affected by the change of pH of ammonia solution which was caused by the water split reactions. The water split reaction occurred at pH of less than 8 in the anodic chamber with producing proton ions, and occurred at pH of more than 11 in the cathodic chamber with producing hydroxyl ions. The pH of the anodic chamber using an anion exchange membrane was sustained to be higher than that using a cation exchange membrane, which resulted in the higher decomposition of ammonia in the anodic chamber. By using the electrolytic characteristics of the divided cell, a continuous electrolyzer with a self-pH adjustment function was newly devised, where a portion of the ammonia solution from a pHadjustment tank was circulated through the cathodic chambers of the electrolyzer. It enhanced the pH of the ammonia solution fed from the pH-adjustment tank into the anodic chambers of the electrolyzer, which caused a higher decomposition yield of ammonia. And then, based on the electrolyzer, a salt-free ammonia decomposition process was suggested. In that process, ammonia solution could be continuously decomposed into the environmentally-harmless nitrogen gas up to 83％, when chloride ion was added into the ammonia solution.

• Korean Journal of Food Science and Technology
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• v.10 no.3
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• pp.313-319
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• 1978

In order to investigate the effect of dietary long chain fatty acids on fatty acid biosynthesis of liver in birds, single comb White Leghron male chicks were fed a fat-free diet an diets containing margaric, stearic and linoleic acids and liver lipid components and liver and plasma fatty acid distributions were compared. Total lipids of tissues were extracted with a chloroform-methanol mixture. The lipid components were determined by thin layer chromatography and fatty acid distribution of lipid fractions were determined by gas liquid chromatography. Fatty acid feeding did not affect liver lipid components. When margaric acid(17 : 0), was fed, 17:0 and heptadecenoic acid(17:1) appeared in every lipid fractions of liver and plasma, and distribution values of these acids were not significantly different between the lipid fractions of liver. In blood plasma of the 17 : 0 fed chicks, however, significantly higher distribution values of 17 : 0 and 17.1 were observed in the triglyceride fraction and in the cholesterol ester fraction, respectively. Dietary stearic acid (18 : 0) did not show any effect on the distribution of 18 : 0 in every lipid fractions of liver but showed a significantly higher distribution value of 18 : 0 in the free fatty acid fraction of plasma. When linoleic acid (18 : 2) was fed, every lipid fractions of liver and plasma contained 18 : 2, especially a significantly higher distribution value was observed in the phospholipid fraction of liver. Dietary margaric and linoleic acids tended to decrease the distribution value of endogenously synthesized palmitoleic (16 : 1) and oleic (18 : 1) acids in liver.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.5
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• pp.467-472
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• 1991

In order to investigate the changes of lipid ingredient and fatty acid content in flint corn by a growth process, total lipids from flint corn(Zea may l.) were extracted, purified and fractionated into three lipid classes (neutral lipid ; NL, glycolipid ; GL, phospolipid ; PL) by silicic acid column chromatography (SACC). Non-polar lipid ingredients and fatty acid contents were determined by thin layer chromatography (TLC) and gas chromatography (GC). And non-polar lipid ingredients were quantitatived by TLC scanner. The crude oil among proximare composition increased 2.74% to 4.43% and NL and PL were fractionated by SACC increased 48.5% to 86.02%, 1.01% to 2.73%, respectively. But GL decreased 50.4% to 11.25%. Neutral lipid ingredients identified monoglyceride, were 1.1~3.7%, 11.9~16.1%, 2.3~4.2%, 16.7~21.5% and 58.5~63.6%, respectively. The major fatty acids of NL were linoleic (48.9~61.0%), oleic(22.3~34.2%), palmitic (10.3~11.7%) acids and stearic, linolenic acids were also detected as minor components. The ratio of total unsaturated fatty acid to total saturated fatty acid presented a higher percentage of 5.87~6.34. The physico-chemical characteristics of flint corn lipids were presented as specific gravity presented 0.920, refractive index 1.468, saponification value 191.2, unsaponificable matter 0.97%, acid value 0.58 and iodine value 124.6, respectively.

• Applied Chemistry for Engineering
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• v.32 no.6
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• pp.653-658
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• 2021

Polyvinylidene fluoride (PVDF) is a promising coating material because of its outstanding processability. The PVDF coating, however, has limitations in anti-corrosion application due to its weak hydrophobicity compared to that of other fluoropolymers. In this study, plasma fluorination was performed using carbon tetrafluoride (CF₄) gas to improve anti-corrosion properties of PVDF. The fluorine content and hydrophobicity of PVDF were investigated in different CF₄ flow rates, followed by the determination of anti-corrosion properties. The fluorine content on the surface of the PVDF film increased by up to 46.70%, but the surface free energy was independent of CF₄ flow rate. Meanwhile, the surface roughness of the PDVF film tended to increase by up to 150% and then decrease with increasing CF₄ flow rate. It is considered that the plasma fluorination affects the surface free energy due to the introduction of fluorine functional groups and surface etching. In addition, the degree of corrosion of the PVDF-coated Fe plate was significantly reduced from 49.2% to 19.0% compared to that of the uncoated Fe plate. In particular, the degree of corrosion of the fluorinated PVDF-coated Fe plate was 13.6%, which was 28.4% lower than that of the PVDF-coated Fe plate, showing improved anti-corrosion protection.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.4
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• pp.321-326
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• 1986

Oyster (Crassostrea gigas), arkshell (Anadare(Scapharce) broughtonii) and sea-mussel (Mytilus edulis) were investigated as to their lipid classes. Lipid extracts from shellfishes were fractionated into neutral lipid (NL), glycolipid (GL) and phospho-lipid (PL) by column chromatography with silicic acid. The fatty acid compositions of their lipid classes and lipid fractions were determined by gas liquid chromatography (GLC). Total lipid contents of shellfishes were $3.5\%$ in the oyster, $1.4\%$ in the arkshell, $1.0\%$ in the sea-mussel. The major fatty acids of total lipids were palmitic acid, eicosapentaenoic acid and docosahexaenoic acid in the oyster and the sea-mussel, palmitic acid, oleic acid and eicosapentaenoic acid in the arkshell. The lipid composition of neutral lipid fractions in shellfishes was separated and identified as free sterol, free fatty acid, triglyceride, hydrocarbon and esterified sterol by TLC. Of these classes, triglyceride fraction was most abundant, amounting to 55.6, 77.7 and $60.4\%$ in the three samples mentioned above, respectively. The main fatty acids of glycolipid were palmitic acid, eicosaenoic acid and docosahexaenoic acid in oyster, myristic acid, palmitic acid and palmitoleic acid in the arkshell, docosahexaenoic acid, linolenic acid and palmitic acid in the sea-mussel. The major fatty acids of phospholipid were palmitic acid, eicosapentaenoic acid and docosahexaenoic acid in the oyster and sea-mussel, palmitic acid, eicosapentaenoic acid and erucic acid in the arkshell.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.3
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• pp.227-233
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• 1986

The compositions and seasonal variations of free sugars and non-volatile organic acids of brown algae, such as Ecklonia cava, Sargassum ringgoldianum and Myagropsis myagroides were investigated by gas chromatography. Four kinds of free sugars, such as xylose, glucose, galactose and floridoside were identified. The most abundant one was floridoside marking 118.7 mg/100 g, 90.9 mg/100 g and 70.0 mg/100 g in Ecklonia cava, Sargassum ringgoldianum and Myagropsis myagroides, respectively. There were not distinguishable seasonal variations in the contents of free sugars in all the samples. In the case of organic acids, nine kinds were identified in Ecklenia cava and major ones were succinic, citric, malic, fumaric, oxalic and lactic acid, of which succinic acid was the most abundant one marking $30.6\%$ of total organic acids. In Sargassum ringgoldianum and Myagropsis myagroides, eight kinds were identified, which major ones were succinic, citric and malic acid in both samples, and they marked $68.4\%$ and $61.1\%$ of total organic acids in Sargassum ringgoldianum and Myagropsis myagroides, respectively. There were not distinct changes in the content of total organic acids according to seasons in all the samples examined. The contents of total organic acics in Ecklonia cava was a little more than Sargassnm ringgoldianum and Myagropsis myagroides.

• Korean Journal of Medicinal Crop Science
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• v.22 no.3
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• pp.188-195
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• 2014

This study was carried to investigate the effect of illite addition on the growth, bioactive components and volatile compounds of leaf on Saururus chinensis Baill cultivation in greenhouse. Illite addition on Saururus chinensis Baill cultivation resulted no significant effects on the aerial part. However, the root part was highest in 5% illite addition group. Crude oil and ash amount increased as illite additives was increased. Ca of inorganics and free sugars contents were highest in 5% and 20% illite addition, respectively. Hyperoside and isoquercetin of available component on leaf were highest in 5% illite addition group, 4.02mg/g and 4.31mg/g, respectively. The volatile compounds in Saururus chinensis Baill leaf cultured with illite addition amounts were isolated by solid-phase microextraction fiber (polydimethysiloxane $65{\mu}m$) and identifed by gas chromatogtaphy mass spectrometry. As the results, the 22 volatile compounds were identified from in Saururus chinensis Baill leaf and major volatile compounds were the ${\alpha}$-cadinol (18.50%), myristicin (16.46%), methyl-9-methyl-tetradecanoate (10.22%), and ${\gamma}$-muurolene (9.75%). Especially, the content of ${\alpha}$-cadinol was highest in 5% illite addition group and ${\gamma}$-muurolene on overall illite addition group was lower than no addition group.

• Journal of Gastric Cancer
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• v.13 no.1
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• pp.51-57
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• 2013

Purpose: Additional gastrectomy is needed after endoscopic resection for early gastric cancer when pathology confirms any possibility of lymph node metastasis or margin involvement. No studies depicted the optimal type of surgery to apply in these patients. We compared the short-term and long-term outcomes of laparoscopic gastrectomy with those of open gastrectomy after endoscopic resection to identify the optimal type of surgery. Materials and Methods: From 2003 to 2010, 110 consecutive patients who underwent gastrectomy with lymphadenectomy either by laparoscopic (n=74) or by open (n=36) for gastric cancer after endoscopic resection were retrospectively analyzed. Postoperative and oncological outcomes were compared according to types of surgical approach. Results: Clinicopathological characteristics were comparable between the two groups. Laparoscopic group showed significantly shorter time to gas passing and soft diet and hospital day than open group while operation time and rate of postoperative complications were comparable between the two groups. All specimens had negative margins regardless of types of approach. Mean number of retrieved lymph nodes did not differ significantly between the two groups. During the median follow-up of 47 months, there were no statistical differences in recurrence rate (1.4% for laparoscopic and 5.6% for open, P=0.25) and in overall (P=0.22) and disease-free survival (P=0.19) between the two groups. Type of approach was not an independent risk factor for recurrence and survival. Conclusions: Laparoscopic gastrectomy after endoscopic resection showed comparable oncologic outcomes to open approach while maintaining benefits of minimally invasive surgery. Thus, laparoscopic gastrectomy can be a treatment of choice for patients previously treated by endoscopic resection.

• Bulletin of the Korean Chemical Society
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• v.32 no.5
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• pp.1569-1574
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• 2011

The presence of replication-competent adenovirus (RCA) subpopulations in adenoviral vector products raises a variety of safety issues for development of therapies based on gene therapy. To analyze the differing effects of adenoviral vector and RCA in vivo, we examined alterations in amino acids (AAs) using rat plasma following injection of ${\beta}$-galactosidase expressing recombinant adenovirus (designated rAdLacZ) or RCA. Plasma AAs were examined by gas chromatography-mass spectrometry. A total of 16 AAs were positively measured. In the rAdLacZ group compared to the control group, the level of aspartic acid was significantly increased (Student's t-test), while the level of glutamic acid was significantly reduced. Additionally, in the RCA group compared to the control group, the level of four AAs, valine, leucine, and isoleucine as branched-chain amino acids, and proline were significantly increased, whereas the levels of three AAs, glycine, threonine, and glutamic acid were significantly reduced. Altered plasma free AA metabolic patterns in rAdLacZ and RCA groups, compared with the control group, may explain the disturbance of AA metabolism related to viral infection.