• Applied Chemistry for Engineering
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• v.28 no.4
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• pp.375-382
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• 2017

In the present review, we provide an overview of the research trend of anodic $TiO_2$ nanostructures. To date, most anodic $TiO_2$ nanostructure formation has focused on the fluoride ion electrolyte system to form nanotube layers. Recently, a novel approach that describes the formation of thick, self-organized $TiO_2$ nanostructures was reported. These layers can be prepared on Ti metal by anodization in a hot organic/$K_2HPO_4$ electrolyte. This nanostructure consists of a strongly interlinked network of nanosized $TiO_2$, and thus provides a considerably higher specific surface area than that of using anodic $TiO_2$ nanotubes. This review describes the formation mechanism and novel properties of the new nanostructures, and introduces potential applications.

• Korean Journal of Food Science and Technology
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• v.38 no.6
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• pp.762-766
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• 2006

To improve water resistance of paperboard used to manufacture the corrugated boxes, effect of surface coating of the liner- board with Na-alginate was investigated by determining the optimum processing conditions such as a optimum alginate concentration for surface coating, plasticizer content, concentration of divalent cations their immersion times, For the surface coating of the liner-board, 2.5% Na-alginate solution was found to be the optimum concentration, and the concentration of glycerol used as plasticizer was effective when 35% alginate concentration was use was Used Immersion of the alginate coated paperboard for 3 min in a $CaCl_2$ solution improved the water resistance properties. As a divalent cation for the insolubilization of the alginate films, $Cu^{2+}$ was found to be as effective as $Ca^{2+}$. Among the platicizers tested, sorbitol was the most effective in reducing water vapor permeability and water solubility of alginate coated paperboard.

• The Korean Journal of Pain
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• v.4 no.2
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• pp.137-141
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• 1991

Percutaneous retrogasserian glycerol rhizolysis(PRGR) was performed in 43 patients, a total of 65 times, for the management of typical trigeminal neuralgia from 1987 to 1991. The age of patients was distributed between 19 and 87 years. According to sex 17 were male and 26 were female. Pure glycerol of 0.3-0.8 ml was injected into the Meckel's cave on the affected site. In 31 PRGR(Group I) that had cisternography to titrate the dose of glycerol, when treated, 26 G of these PRGR patients(83.9%) had relief of pain. There were recurrence of pain in 7PRGR (22.6%) and the average interval from the PRGR to recurrence of pain in 7 PRGR(22.6%) and the average interval from the PRGR to recurrence of pain was 16.9 months. In 34 PRGR(Group II) of which bupivacaine was injected to titrate the dose of glycerol, 29 PRGR(85.3%) had relief of pain 80 howing treatment. There were recurrence of pain in 8 PRGR(23.5%) and the average interval from the PRGR to the recurrence of pain was 14.3 months. Finally of all procedures done(65 PRGR), 55 PRGR(84.6%) had relief of pain. There were recurrence of pain in 15 PRGR(23.1%) and the average interval from the PRGR to recurrence of pain was 15.5 months. There was no significant difference between the two groups in the rate of pain relief. There were conjunctival irritation(3 cases), headache(2), vomiting(3), hematoma(2), and herpes simplex(3) as transient complications after PRGR. Corneal ulceration and anesthesia dolorosa did not develop in any cases.

• The Korean Journal of Food And Nutrition
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• v.11 no.5
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• pp.542-549
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• 1998

Dietary orotic acid is known to induce the fatty liver. Fatty acid profiles in the lipid fraction of the liver and the serum in rats fed with or with orotic acid diet were analyzed. In all the hepatic lipid fraction of rats fed on the supplemented orotic acid diet, there was a significant increased in linoleic acid. In addition, linoleic acid was also increased in the triacylglycerol fraction of hepatic endoplasmic reticulum and the triacylglycerol and diacylglycerol fractions of hepatic Golgi apparatus of the orotic acid-feeding rats. In the time course study of the fatty acid profile in the hepatic triacylglycerol and diacylgycerol fractions, an increase of linoleic acid was observed similarly in the initial stages of orotic acid intake in the both fractions. However, linoleic acid in the serum triacylglycerol fraction of orotic acid-feeding rats increased from day 1, but it began to decrease the increment from day 2, resulting in the lower level of linoleic acid in the serum triacylglycerol fraction of orotic acid-feeding rats than that of rat fed a orotic acid-free diet after 10 days. Oleic acid (18:1) was increased in the only cholesteryl ester fraction of helpatic. However, oleic acid level in other fractions was not changed. The compositions of 14:0, 16:0 and 18:0 was reduced in the hepatic triacylogylcerol, diacylglycerol and cholesteryl ester fractions by orotic acid-feeding. However, these saturated fatty acids were significantly increased in the serum triacylglycerol fractions. The orotic acid indcued changes in linoleic acid level in hepatic triacylglycerol may be explained by the impaired fatty acid metabolism and limited excretion of this fatty acid from liver to serum.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.176.2-176.2
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• 2011

피마자유(Castor oil)는 합성수지, 그리스, 유압용 오일, 윤활기유 등의 다양한 용도로 쓰이는 오일로서 점도가 높고 무색에서 황갈색을 띈다. 피마자유 추출은 압착 착유 또는 용매 추출로 얻게 되며 본 실험에 사용된 오일은 압착 착유한 것으로 매우 진한 갈색을 띄는 정제전 오일을 이용하였다. 실험에 사용된 피마자유의 초기 산가는 1mgKOH/g 이하로 낮은 유리지방산 함량을 보였으며 수분은 0.3%로 전이에스테르화 반응을 위해서는 수분 증발이 필요했다. 피마자유의 바이오디젤 생산을 위해 진행된 물성 분석 항목은 산가, 수분, 인함량, 황함량, 점도, 고형물이며 원료유와 그 바이오디젤에 대해 각각 물성 분석을 실시하였다. 피마자유의 가장 큰 특징은 다른 식물성 오일과는 다르게 오일이 알코올에 녹는 특성이 있으며 이런 이유로 전이에스테르화 반응 후 바이오디젤과 글리세롤이 분리되지 않는 문제점을 갖고 있다. 피마자유를 이용해 제조한 바이오디젤, 즉 지방산메틸에스터의 함량을 분석한 결과 약 90%의 메틸에스터화 반응 전환율을 나타내었으나 국내외 품질규격상의 탄소수 C14~C24:0의 지방산 에스터(fatty acid methyl esters)로 검출되는 바이오디젤의 함량은 10% 미만으로 나타났으며 나머지 90%는 라이신올레익산메틸에스터(ricinoleic acid methyl ester)로 분석되었다. 따라서, 기존의 대두유, 유채유, 팜유, 폐식용유로부터 제조한 바이오디젤과 물성이 매우 상이하고 특히 끊는점(boiling point)과 점도가 높아 경유 대체연료로는 활용이 불가능할 것으로 판단된다. 하지만 기존의 다양한 용도의 오일로 사용하기 위해 정제하는 과정에서 전체 착유 오일중의 약 10%만을 선택적으로 분리하여 바이오디젤 원료로 활용하는 방안은 가능할 것으로 판단된다.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.589-593
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• 2007

재생 가능한 자원인 동식물성 기름을 원료로 제조되는 수송용 연료 바이오디젤은 낮은 대기오염물질 배출과 $CO_2$ Neutral 특성으로 환경친화적인 연료로 인정을 받으며 전세계적으로 그 생산량이 급격히 증가하고 있다. 대부분의 상용화 공정은 염기촉매를 이용한 전이에스테르화 반응에 근거하고 있으며 높은 생산성을 위해 연속 공정을 채택하고 있다. 원료유 중의 유리지방산(free fatty acid, FFA)은 염기 촉매와 반응하여 지방산염(Soap)과 수분을 생성하며 반응촉매의 투입양을 증가시카고 반응 후에 글리세롤과 지방산 메틸에스테르와의 분리를 어렵게 만든다. 높은 수율과 후속공정의 부하를 줄이기 위해서는 식물성 원료유 중의 FFA는 고체 산촉매 하에서 메탄올과 에스테르화 반응시켜 전환 제거되어야 한다. 본 연구에서는 고체산 촉매인 Amberlyst-15을 충전한 4단 PBR(Packed Bed Reactor, 충전율 60%(v/v))에서 반응시간과 반응온도에 따른 대두원유의 전처리 효율을 조사하였으며 최적 전처리 조건을 도출하였다. 최적 전처리 조건에서 대두원유는 초기 산가 1.6에서 0.4-0.6으로 연속 전처리할 수 있었다. 본 연구에서는 연속 흐름 반응기인 PFR(Plug Flow Reactor)와 4단 CSTR(Continuous Stirred Tank Reactor)에서 균질계 촉매인 KOH 존재하에 대두유와 메탄올과의 전이에스테르화 반응 특성을 조사하였으며 각 연속 반응시스템에서 최적 운전 조건을 도출하였다. PFR 반응기에서 반응온도, 반응시간, 반응물 흐름방향, static mixer(SM) 개수에 따른 반응특성을 조사한 결과, PFR에서의 최적 반응조건은 하향류 흐름 방향과 3개의 SM를 설치한 조건에서 반응시간 5.8분, 반응온도 90$^{\cdot}C$, 메탄올:오일 몰비 9:1, KOH 농도 0.8%로 도출되었다. CSTR 반응기에서는 반응온도와 체류시간에 따른 반응특성을 조사하였으며 최적반응 조건으로 반응온도 80$^{\cdot}C$, 메탄올/오일 몰비 9:1, KOH 농도 0.8%, 체류시간 18.4분, 교반속도 250rpm로 조사되었다.

• Archives of Plastic Surgery
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• v.35 no.5
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• pp.626-629
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• 2008

Purpose: We investigate the possibility of vessel preservation with glycerol and evaluate the potential of preserved gastroepiploic artery as a tool for the microsurgical practice. Methods: In 5 early gastric cancer patients, IRB(No. C-0603-040-170), we gained gastroepiploic artery specimens(5 segments, about 10 cm) after gastrectomy. Each segment was rinsed in a normal saline and subsequently placed in a bottle, containing 50 mL anhydrous glycerol (87%). The bottles were refrigerated at $4^{\circ}C$, the longest preservation time being 5 months. Results: At first glance, no fragmentation was detected and the surface of vessel seemed mild sclerotic. In histological examination, vascular structures remained intact though preservation with glycerol led to a mild atrophy of the smooth muscle in the tunica media. Especially, we found out the elastic fibers and endothelial lining of the intima were preserved until 5 months. Adequate status for using microsurgical practice was also maintained and leakage test was performed successfully with gentian violet ink. Conclusion: Based on the results obtained in this study, the gastroepiploic artery preservation with glycerol as a training model for microvascular anastomosis is a technically very simple procedure and useful for the novice microsurgeon.

• Journal of the Korean Applied Science and Technology
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• v.15 no.4
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• pp.35-44
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• 1998

All the triacylglycerols including the molecular species having ${\Delta}^5$-unsaturated fatty acids from the seeds of Pinus Koraiensis, were split into a mixture of diacylglycerols by a Grignard reagent prepared with allyl bromide without arousing acyl chains of a glycerol moiety to migration, and were also easily partially hydrolyzed to diacylglycerols by pancreatic lipase. (S)-(+)-(1-naphthyl)ethyl urethane(NEU) derivatives of the diacylglycerol mixture derived from the triacylglycerols were fractionated into sn-1, 3-, sn-1, 2- and sn-2, 3-DG-NEU by silica-HPLC and the fatty acid composition of these fractions was analysed. $C_{18:1{\omega}9}$ is distributed evenly in the three positions of TG with $C_{18:2{\omega}6}$ mainly located in sn-2 position, while ${\Delta}^5$-unsaturated fatty acids such as ${\Delta}^{5.9}-C_{18:2}$, ${\Delta}^{5.9.12}-C_{18:3}$ and ${\Delta}^{5.11.14}-C_{20:3}$ are exclusively present in the sn-3 position. These results could be confirmed by $^{13}C$-NMR spectroscopy : the signals at $^{\delta}$173.231 ppm and $^{\delta}$172.811 ppm of the carbonyl carbon of acyl moieties indicate the presence of saturated acids and/or $C_{18:1{\omega}9}$ (oleic acid) in the ${\alpha}({\alpha}')$- or ${\beta}$- positions, and $C_{18:2{\omega}6}$ including $C_{18:1{\omega}9}$ in the ${\beta}$-position, respectively. In addition, the resonance at $^{\delta}$173.044 ppm suggested a location of ${\Delta}^5$-unsaturated fatty acid moiety in the ${\alpha}({\alpha}')$-position.

• KSBB Journal
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• v.21 no.6 s.101
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• pp.418-421
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• 2006

Fatty acid methyl esters, also referred to as biodiesel, have been determined to have a great deal of potential as substitutes for petro-diesel. In order to enhance productivity in the biodiesel production process, feedstocks were previously recommended to be anhydrous, with a free fatty acid content of less than 0.5%. In this study, the effects of several catalysts, methanol molar ratio, catalyst amount, and reaction time on the reduction of free fatty acid level were studied with a simulated feedstock consisting of 20% oleic acid in rapeseed oil. Ferric sulfate was selected as the best catalyst. Increasing the catalyst amount and methanol molar ratio is very effective in decreasing the acid value of the simulated mixture. Our results may provide useful information with regard to the development of more economic and efficient free fatty acid removal system.

• KSBB Journal
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• v.31 no.4
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• pp.246-255
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• 2016

Co-production of 3-hydroxypropionic acid (3-HP) and 1,3-propanediol (1,3-PDO) was suggested as an innovative strategy to overcome several limitations occurring in the single production of 3-HP from glycerol. In this study, two new isolates of Klebsiella pneumoniae, which produce less lipopolysaccharide (LPS) thus considered less pathogenic than K. pneumoniae DSM 2026, were compared and evaluated for their potential for the co-production of 3-HP and 1,3-PDO. The newly isolated strains showed significantly faster sedimentation rate than DSM, which should be beneficial for downstream processing. Analysis of genome sequences of the isolates confirmed the presence of all genes necessary for glycerol assimilation, 1,3-PDO production and biosynthesis of coenzyme $B_{12}$. Co-production yield was highest under anaerobic condition while cell growth was highest under aerobic condition. Both strains showed similarly good performance for the co-production although J2B gave the slightly higher co-production yield of 0.80 mol/mol than GSC021 (0.75 mol/mol). The evaluation of the newly developed strains presented here should be useful in designing similar evaluation experiments for other microorganisms.