• Special Issue of the Society of Naval Architects of Korea
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• 2013.12a
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• pp.1-7
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• 2013

In past decades, a maximum standard vessel size for chemical tankers is not normally larger than 55,000 TDW due to the characteristic of chemical product shipment which is so variable but small quantity unlike single product carries such as crude oil tankers. These days, as demand of very large chemical tanker is rising due to the change of market trend of chemical product shipment, 75,000 TDW class chemical tanker has been developed. The newly developed vessel's structure has been designed based on CSR (Common Structural Rule) for double hull oil tankers (hereafter CSR) published by IACS (International Association of Classification Societies). However, due to the large difference from typical oil tankers, many items should be specially considered such as on deck transverse and corrugated bulkheads. In addition, two longitudinal bulkheads without upper stool have been constructed in order to maximise the number of cargo tanks and the volume of each cargo tanks. In this study, key word of the vessel has been briefly reviewed and the structural reliability of the proposed vessel has been investigated.

• Journal of Microbiology and Biotechnology
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• v.9 no.5
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• pp.624-630
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• 1999

In order to investigate the position of various fatty acids attached to glycerol and the specificity of Lipolase-100T, hydrolysis of fish oil was carried out with Lipolase-100T derived from Aspergillus oryzae. The amounts of free fatty acids produced from triglyceride, 1,2(2,3)-diglyceride, 1,3-diglyceride, and 2-monoglyceride and conversion rates of 1,2(2,3)-diglyceride to 1,3-diglyceride and 2-monoglyceride to 1(3)-monoglyceride were also calculated. The ratio of 1,2-diglyceride content to 1,3-diglyceride was higher than 70 in the early period of hydrolysis. The fatty acid content of the glyceride mixture after 72 h of hydrolysis was compared with that of fish oil, and it was found that polyunsaturated fatty acids such as C16:4, C20:4 n-3, C20:5 n-3, C21:5 n-3, C22:5 n-3 and C22:6 n-3 were located in the 2-position of glycerol. Material balance of each component in the hydrolysis system was written to obtain a set of simultaneous linear equations. The theoretical quantity of free fatty acids produced from triglyceride, 1,2-diglyceride, 1,3-diglyceride, and monoglyceride, respectively, were calculated by solving the linear equation system. The conversion rate of 1,2(2,3)-diglyceride to 1,3-diglyceride and that of 2-monoglyceride to 1(3)-monoglyceride were also obtained. The results showed that the migration rate of 1,2(2,3)-diglyceride to 1,3-diglyceride was higher than the hydrolysis rate of 1,2(2,3)-diglyceride to 2-monoglyceride and the conversion rate of 2-monoglyceride to 1(3)-monoglyceride was extremely low.

• Natural Product Sciences
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• v.26 no.1
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• pp.64-70
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• 2020

Citrus junos seeds (CS) have been traditionally used for the treatment of cancer and neuralgia. They are also used to manufacture edible oil and cosmetic perfume. A large amount of CS shells without oil (CSS) are discarded after the oil in CS is used as foods or herbal remedy. To efficiently utilize CSS as a by-products, it needs to be studied through chemical analysis. Therefore, we developed an ultra-performance liquid chromatography (UPLC)-diode array detection (DAD) method for simultaneous determination and quantitative analysis of five components (two flavonoids and threes limonoids) in CSS. A Waters Acquity UPLC HSS T3 column C18 (2.1 × 100 mm, 1.8 ㎛) was used for this separation. It was maintained at 40 ℃. The mobile phase used for the analysis was distilled water and acetonitrile with gradient elution. To identify the quantity of the five components, a mass spectrometer (MS) with an electrospray ionization (ESI) source was used. The regression equation showed great linearity, with correlation coefficient ≥ 0.9912. Limits of detection (LOD) and limits of quantification (LOQ) of the five compounds were 0.09 - 0.13 and 0.26 - 0.38 ㎍/mL, respectively. Recoveries of extraction ranged from 97.45% to 101.91%. Relative standard deviation (RSD) values of intra- and inter-day precision were 0.06 - 1.15% and 0.19 - 0.25%, respectively. This UPLC-DAD method can be validated to simultaneously analyze quantities of marker flavonoids and limonoids in CSS.

• Journal of the Korean Professional Engineers Association
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• v.34 no.5
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• pp.82-88
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• 2001

Mackerel(Scomber japonicus), pacific saury (Cololabis saira) and sardine(Sardinops melanosticta) is widely distributed in coastal seawater of Korea, these fishes are not effective utilization as processing material cause by rapid lipid oxidation and off flavour. This study was attempted to lipid distribution in body section, whole body, meat, viscera, skin and head, and fatty acid composition of the oils obtained from these body section. The content of total lipid of mackerel, pacific saury and sardine were 12.48%, 12.79% and 13.81% respectively, and lipid contents in different body section of mackerel was muscle 2.31%, viscera 3.54%, skin 1.43% and head 5.20%, while in cause of sardine was muscle 4.17%, viscera 3.15%, skin 1.72%, and head4.77%. The major saturated fatty acids of mackerel, pacific saury and sardine oil were C$\_$16:0/(palmitic acid), C$\_$18:0/(stearic acid), C$\_$14:0/(myristic acid), and monoenoic acids was C$\_$18:0/(oleic acid), C$\_$16:1/ (palmitolic acid), C$\_$22:0/(erucic acid) and C$\_$20:1/(gadoleic acid), in cause of polyenoic acid was C$\_$22:6/(DHA, docosahexaenoic acid), C$\_$20:0/(EPA, eicosapentaenoic acid), C$\_$22:4/(behenic acid), C$\_$18:2/(linoleic acid) high quantity in order. When fresh oil extracted from mackerel, pacific saury and sardine was stored for 20 days at 5$\^{C}$, carbonyl and acid value of oil increased with storage day, but peroxide value decreased after 15 days.

• Proceedings of KOSOMES biannual meeting
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• 2005.05a
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• pp.111-118
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• 2005

The Protocol adopted in Sep. 1997 included the new Annex VI of MARPOL 73/78, which will enter into force on 19 May 2005. MARPOL Annex VI sets limits on sulphur oxide and nitrogen oxide emissions from ship exhausts and prohibits deliberate emissions of volatile organic compound (VOCs) from oil tanker in port and oil terminal. This study was conducted to find out countermeasures for the new Annex VI of MARPOL 73/78 and draw up a feasible management plan. The emission quantity of NOx and SOX from ships in Ulsan Port was calculated by U.S. EPA and Japan Marine Engineering emission factors of air pollutant from ship exhausts. In addition, volatile organic compound (VOCs) from oil tanker during the loading and discharging period, also calculated.

• 한국태양에너지학회:학술대회논문집
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• 2009.11a
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• pp.279-284
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• 2009

Traditionally, so-called "industrial waste gases", such ad exhaust from boilers at industrial installations and a large quantity of soot discharged from power station, before their release into the atmosphere, have been on occasion subjected to an air cleaning process to remove fine particles that may pollute the atmosphere (such as mist and dust containing various powdery or oily substances and moisture from industrial waste gases). The release of industrial waste gases containing these particles directly into the atmosphere poses a serious threat to the earth environment; and recovery of these noxious substances is required by law in some countries and local governments. in urban areas, air pollution from automobile exhaust and others creates a serious condition. Some homes are equipped with and use indoor air purifiers. In many of the kitchens of restaurants, smoke generated during cooking and otherwise contaminated air are cleansed by air purifiers before being released outside or recycled inside. For the dust collecting devices to recover the fine particles contained in contaminated air, the cause for air pollution and how to purify air, many types based on various principles are known. Specifically, classified based on theories of particle collection, filtration, gravity, inertia, centrifugation, electricity, and cleaning types are cited as available processes. Among them, an appropriate type is selected according to the size or type of fine particles to be collected and conditions for installation. For the efficiency of dust collection, a filtration system (by using bag filters and others) and electric system are particularly outstanding and are therefore used widely in various areas of industry. In this research, rotary type high performance oil mist and smoke collecting system with self auto cleaning device equipped with the cleaning fluid spraying section is investigated.

• The Korean Journal of Food And Nutrition
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• v.32 no.4
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• pp.284-293
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• 2019

This study investigated the volatile flavor composition of essential oils from Ligularia fischeri and Ligularia fischeri var. spiciformis. The essential oils obtained from the plants were analyzed by gas chromatography (GC) and GC-mass spectrometry (GC-MS). 99.63% volatile flavor compounds were identified in the essential oil from the L. fischeri. The major compounds were (E)-3-hexenol (30.73%), longiverbenone (13.23%), viridiflorol (12.39%), ${\gamma}$-muurolene (7.32%), limonene (6.12%), and caryophyllene (${\beta}-4.24%$). 99.76% volatile flavor compounds were identified in the essential oil from the L. fischeri var. spiciformis. The major compounds were ledol (42.81%), (E)-15-heptadecenoic acid (33.91%), ${\beta}$-bisabolol (3.23%), viridiflorol (3.08%), and cis-${\alpha}$-farnesene (2.60%). Although the two plants are very similar, the chemical composition of the essential oils was significantly different in quality and quantity. In the case of L. fischeri., it has high contents of monoterpene and sesquiterpene. (E)-3-hexenol, longiverbenone, ${\alpha}$-phellandrene, and ${\alpha}$-myrcene were regarded as the characteristic odorants of L. fischeri, but they were not identified in L. fischeri var. spiciformis. Ledo, (E)-15-heptadecenoic acid, and ${\beta}$-bisabolol were regarded as the characteristic odorants of L. fischeri var. spiciformis, but they were not identified in L. fischeri. The ratio of limonene, ${\gamma}$-muurolene and viridiflorol can be used as an indicator to distinguish between these two plants.

• Tribology and Lubricants
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• v.35 no.2
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• pp.132-138
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• 2019

In this study, we demonstrate the effects of the acidic properties of montmorillonite (MMT), which is commonly used as a catalyst, on the conversion and selectivity of the dimer acid methyl ester (DAME) synthesis. We synthesize DAME by the dimerization of conjugated linoleic acid methyl ester (CLAME) and oleic acid methyl ester using MMT KSF. Incidentally, trimer acid methyl ester was formed as a by-product during the DAME synthesis. There is a necessity to adequately adjust the strength and quantity of the acid site to control the selectivity of DAME. Therefore, we vary the pH of the MMT acid by using various metal hydroxides. The purpose of this study is to increase the yield of monocyclic dimer acid methyl ester, which is a substance with adequate physical properties for industrial applications (e.g., lubricant and adhesive, etc.), using a heterogeneous catalyst. We report the dimerization of fatty acid methyl ester by using base treated-KSF, and apply it to conjugated soybean oil methyl ester. Then, we transmute the acid site properties of KSF, such as pH of 5 wt.% slurry KSF and various alkali metals (Li, Na, K, Ca). Characterization of base treated-KSF using a pH meter, x-ray diffraction, inductively coupled plasma-atomic emission spectrometer, Brunauer-Emmett-Teller surface analysis, and temperature-programmed desorption. We conduct an analysis of CLAME and DAME using nuclear magnetic resonance spectroscopy, gas chromatography, and gel permeation chromatography. Through these experiments, we demonstrate the effects of the acidic properties of KSF on the conversion and selectivity of the DAME synthesis, and evaluate its industrial potential by application to waste vegetable oil.

• Journal of Electrochemical Science and Technology
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• v.13 no.2
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• pp.308-320
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• 2022

The high internal resistance (R_int) that develops across the sediment microbial fuel cells (SMFC) limits their power production (~4/10 mW m^-2) that can be recovered from an initial oil-contaminated sediment (OCS). In the anolyte, R_int is related to poor biodegradation activity, quality and quantity of contaminant content in the sediment and anode material. While on the catholyte, R_int depends on the properties of the catholyte, the oxygen reduction reaction (ORR), and the cathode material. In this work, the main factors limiting the power output of the SMFC have been minimized. The power output of the SMFC was increased (47 times from its initial value, ~4 mW m^-2) minimizing the SMFC R_int (28 times from its initial value, 5000 ohms), following the main modifications. Anolyte: the initial OCS was amended with several amounts of gasoline and kerosene. The best anaerobic microbial activity of indigenous populations was better adapted (without more culture media) to 3 g of kerosene. Catholyte: ORR was catalyzed in birnessite/carbon fabric (CF)-cathode at pH 2, 0.8M Na₂SO₄. At the class level, the main microbial groups (Gammaproteobacteria, Coriobacteriia, Actinobacteria, Alphaproteobacteria) with electroactive members were found at C-anode and were associated with the high-power densities obtained. Gasoline is more difficult to biodegrade than kerosene. However, in both cases, SMFC biodegradation activity and power output are increased when ORR is performed on birnessite/CF in 0.8 M Na₂SO₄ at pH 2. The work discussed here can focus on bioremediation (in heavy OCS) or energy production in future work.

• Korean Chemical Engineering Research
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• v.47 no.6
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• pp.762-767
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• 2009

In this study, the feasibility of using vegetable oil extracted from tropical crop seed as a biodiesel feedstock was investigated by producing biodiesel and analysing the quality parameters as a transport fuel. In order to produce biodiesel efficiently, two step reaction process(pre-treatment and transesterificaion) was required because the tropical crop oil have a high content of free fatty acids. To determine the suitable acid catalyst for the pre-esterification, three kinds of acid catalysts were tested and sulfuric acid was identified as the best catalyst. After constructing the experimental matrix based on RSM and analysing the statistical data, the optimal pre-treatment conditions were determined to be 26.7% of methanol and 0.982% of sulfuric acid. Trans-esterification experiments of the pre-esterified oil based on RSM were carried out, then discovered 1.24% of KOH catalyst and 22.76% of methanol as the optimal trans-esterification conditions. However, the quantity of KOH was higher than the previously established KOH concentration of our team. So, we carried out supplemental experiment to determine the quantity of catalyst and methanol. As a result, the optimal transesterification conditions were determined to be 0.8% of KOH and 16.13% of methanol. After trans-esterification of tropical crop oil, the produced biodiesel could meet the major quality standard specifications; 100.8% of FAME, 0.45 mgKOH/g of acid value, 0.00% of water, 0.04% of total glycerol, $4.041mm^2/s$ of kinematic viscosity(at $40^{\circ}C$).