• Korean Journal of Food Science and Technology
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• v.11 no.4
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• pp.291-297
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• 1979

The experimentally cultivated potatoes of 4 varieties, Irish Cobbler, Warba, Shimabara, and Saco were dried in a frozen state, powdered subsequently and subjected to the extraction of free and bound lipids. Constituents of the prepared lipids were fractionated, quantified, and compared by the methods of column and gas-liquid chromatographies. The results were summarized as follows : 1. The total crude lipid content in potato on a dry weight basis was 0.57 % of which 0.2 % was free lipid and 0.37 % was bound lipid. 2. The neutral lipid content in the free lipid was 14.9 %, approximately 3 times as much as the 4.5 % contained in the bound lipid, whereas the glycolipid content in the free lipid was 15.1 %, slightly less than 22.2 % contained in the bound lipid. However, the phospholipid content was 33.9 % in the bound lipid, approximately 4.5 times as much as the 7.2 % contained in the free lipid. This fact revealed that the bound lipid consisted mainly of polar lipid, while the free lipid consisted of neutral lipids, glycolipids and phospholipids in about the same proportion. 3. The main fatty acids constituting more than 90 % in the free and bound lipids were linoleic, palmitic and linolenic acids. The content of the saturated fatty acid was slightly less in the free lipid than in the bound lipid, whereas the unsaturated fatty acids were more abundant in the free lipid.

• Journal of the Korean Applied Science and Technology
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• v.34 no.4
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• pp.1085-1093
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• 2017

Plasticizers are materials added to give softness and elasticity to plastics having rigid properties to give soft properties as products, and they are mainly added to high molecular materials to give flexibility to improve workability and to improve cold resistance, resistance to volatility and electrical properties. It is used for the purpose. Most plasticizers are inert liquids, similar in function to solvents but with high molecular weight and no volatility. In addition, when dissolved in petrochemical products, only the plasticizer is separated by the matrix effect with other compounds, and qualitative and quantitative analysis. In this study, qualitative and quantitative analysis of DOA and DOP, which are representative components of petrochemical products, were conducted using MD-GC/MS and developed an optimal plasticizer analysis method.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.10
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• pp.100-106
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• 2019

Ground and high altitude simulated combustion experiments were conducted using a liquid rocket engine with hydrogen peroxide and kerosene as the propellant. A ground and high altitude simulated combustion test facility was constructed by installing a high altitude model diffuser and TMS (Thrust Measuring System) on a vertical combustion test bench. The thrust characteristics according to altitude were investigated using the combustion test equipment. The diffuser was designed on a 1:4.8 scale to verify the characteristics of the high diffusing diffuser and starting pressure. The cold flow tests were conducted using nitrogen gas, and the performance characteristics and starting characteristics of the scale down diffuser were verified. A diffuser and TMS were installed on the vertical combustion test bench, and the thrust correction equations for the system resistance were derived. The thrust correction equations were derived from the step test and vacuum step test before the actual hot firing test. Nozzles with an operating altitude of 10km were designed. Hot firing tests were conducted to analyze the thrust characteristics according to the operating altitude changes. The actual thrust was calculated using each correction equation with the thrust value measured by the TMS.

• The Korean Journal of Malacology
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• v.9 no.1
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• pp.1-16
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• 1993

한국의 담수에 광범위하게 서식하고 있으면서 역학적으로 중요한 역할을 하고 있는 두 종의 복족류 즉 쇠우렁이(Parafossarulus manchouricus)와 물달팽이(Radix auricularia coreana)의 소화기관 중에서 식도, 소화선 및 장에 대한 미세구조 관찰을 시도하였다. 이 부위들은 간흡충(간디스토마)과간질(소간디스토마)의 유생들이 그들의 생활사 중 거쳐가는 곳으로 알려진 소화관들이어서 이후 흡충류의 유충들이 위의 소화관에 주는 영향을 연구하는데 필요한 기초자료를 얻고자 수행된 것이었다. 관찰해 본 결과 다음과 같은 결론을 얻을 수 있었다. 식도의 상피조직은 두 종류에서 공히 원주세포와 원주섬모세포 및 점액분비 세포로 이루어져 있었다. 식도강상피 내에서도 어느 정도의 흡수와 소화가 이루어 지고 있음은 특이한 현상이라 하겠다. 소화선은 두 종에서 공히 복분지 관상선으로서 그 상피는 micovilli를 선강 또는 도관에 연한 유리표면에 가지고 있어 brush boredr을 이루고 있는 원주세포과 원주섬모세포로 구성되어 있었다. 이들 세포들의 내부 구조로 보아 소화세포와 배석세포로 구분할 수 있었다. 장의 상피는 원주세포와 원주섬모세포로 구성되어 있었으며 이들도 장강에 연한 유리표면에는 brush border를 이루고 있었다. 흡수와 분비기능이 활발한 것으로 사료된다. 전반적으로 보아 본 연구에서 관찰한 두 복족류의 소화관은 모든 부위에서 세포의 유리표면에 microvilli를 가지고 있어 물질의 흡수기능을 가지고 있음을 시사해주고 있었고, 이들 세포 중에는 때로 밀집한 cilia를 가지고 있어 소화관 내의 액체물질이나 이에 내포된 미세입자들의 유동을 도와주고 있음을 추측할 수 있었다.)은 결합조직으로 이루어진 근육질의 두꺼운 벽을 가지고 있었으며 내강은 돌출부위에 의해 4부분으로 갈라져 있었다. 내강에 연한 상피는 원주세포로 되어 있었다. 상음경(epiphallus)의 벽은 근섬유 다발은 벽의 외곽으로 갈수록 밀도가 높아졌다. 상부에 내강과 연결되는 함입구조(groove)를 가지며, 내강에 연한 상피는 섬모가 없는 원주세포로 이루어져 있었다. 음경(penis)은 근섬유가 산재된 두꺼운 벽을 가졌으며 상음경보다 굵은 원통형이었다. 내강은 많은 돌출부에 의해 복잡하게 나뉘어 있으며 상피세포는 원주 세포로 이루어져 있었고 섬모는 관찰되지 않았다. 내강 내의 분비물과 세포의 형태로 보아 내강상피세포는 분비기능을 가진 것으로 사료된다.술적 문제가 적절히 해결되는 경우 비활성 가스 제너레이터는 민수용으로는 대형 빌딩, 산림, 유조선 등의 화재에 매우 적절히 사용되어 질 수 있을 뿐 아니라 군사적으로도 군사작전 중 및 공군 기지의 화재 그리고 지하벙커에 설치되어 있는 고급 첨단 군사 장비 등의 화재 뿐 아니라 대간첩작전 등에 효과적으로 활용될 수 있을 것으로 판단된다.가 작으며, 본 연소관에 충전된 RDX/AP계 추진제의 경우 추진제의 습기투과에 의한 추진제 물성 변화는 미미한 것으로 나타났다.의 향상으로, 음성개선에 효과적이라고 사료되었으며, 이 방법이 편측 성대마비 환자의 효과적인 음성개선의 치료방법의 하나로 응용될 수 있으리라 생각된다..7%), 혈액투석, 식도부분절제술 및 위루술·위회장문합술을 시행한 경우가 각 1례(2.9%)씩이었다. 13) 심각한 합병증은 9례(26.5%)에서 보였는데 그중 식도협착증이 6례(17.6%), 급성신부전증 1례(2.9%), 종격동기흉과 폐염이 병발한 경우와 폐염이 각

• Clean Technology
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• v.25 no.1
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• pp.19-32
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• 2019

As regional air pollution gets worse by the sulfur oxides emitted from various types of vessels passing through the many countries, the International Maritime Organization establishes the emission control areas and regulates sulfur dioxide in those areas. In order to satisfy these regional regulations, the fuel selection method and the exhaust gas post-treatment device are applied to the ships. Due to the economic reasons, the post-treatment method of exhaust gas for reducing the amount of sulfur oxides discharged is mainly preferred. The scrubber which is dominantly used in the ships are the spray type system where the sprayed liquid drops used for capturing the soluble sulfur dioxides in the exhaust gas. The performance of the spray type system depends on the size distribution of the sprayed droplets. In order to evaluate this performance, we designed counterflow type scrubber and cyclone scrubber and evaluated the desulfurization efficiency and the amount of droplet evaporation according to the size of each droplet by using computational fluid dynamics. The Eulerian-Eulerian analysis method was used because the scrubber had a gas-liquid two-phase flow inside the scrubber. When the diameter of the droplet was $100{\mu}m$, $300{\mu}m$, $500{\mu}m$ and $700{\mu}m$. As a result, both of scrubbers showed high desulfurization efficiency and low evaporation amount at $500{\mu}m$ and $700{\mu}m$.

• Membrane Journal
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• v.30 no.6
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• pp.443-449
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• 2020

In this study, CO2 separation experiment was performed on a CH4/CO2 mixed gas using a ceramic hollow fiber membrane contactor module (HFMC). In order to fabricate high-durability HFMC, a high-durability hollow fiber membrane was prepared and evaluated. HFMC was fabricated using the prepared hollow fiber membrane, and the experiment used a mixture of CH4/CO2 (30% CO2, CH4 balance) and monoethanolamine (MEA). During HFMC operation, the effect of gas and absorbent pressure on the CO2 removal efficiency was evaluated. The CO2 removal efficiency increased as the gas pressure increased, and the CO2 absorption flux also showed a tendency to increase with the liquid flow rate. In addition, when the CO2 absorption rate was less than 40%, LTS-1, a counter-current form where the absorbent enters from the bottom, has higher CO2 removal performance than LTS-2, a countercurrent form in which the absorbent enters from the top. and when the absorption rate was 40% or higher, LTS-2 had higher performance than LTS-1.

• Journal of Practical Agriculture & Fisheries Research
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• v.9 no.1
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• pp.121-132
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• 2007

1. 버섯종균 개선 버섯의 품질과 수량을 좌우하는 주요 요인은 종균의 활력이다. 그러나 라오스에서는 종균의 활력이 낮아 조그마한 100cc 병에 배양완성하는데 14일이 소요되는 등 볍씨종균의 균사생장과 균사밀도가 매우 낮음을 확인하였다. 따라서 100cc 병을 1000cc 비닐봉지로 개선하여 입봉하는데 소요되는 시간을 10배로 단축 개선하였다. 또한 곡립종균을 액체종균으로 대처한 결과 균사생장속도가 2배가 빨랐으며 작업속도가 4배가 빨라졌다. 2. 버섯배지제조 방법 개선 미세하고 건조한 톱밥에 수분을 첨가하는데 50%이하의 수분함량을 유지함으로서 균사가 표면에만 자라고 있는 것을 확인하고 버섯 배지제조 시 물리성을 개선하기 위하여 볏짚을 잘게 잘라 10%~100%까지 혼합하는 실험을 실시하였다. 그 결과 톱밥 50%에 볏짚 50% 혼합하는 것이 균사생장 속도와 밀도가 좋았다. 또한 왕겨도 30%정도 혼합한 배지처리에서 가장 좋았다. 또한 수분함량도 65%로 향상하여 혼합하도록 지도하였다. 3. 버섯배지살균 방법 개선 라오스에서는 왕겨를 태워 살균을 실시하고 있다. 화력이 약하여 살균한 배지에서 볍씨의 새싹이 돋아나오는 경우를 발견하였다. 이는 살균이 제대로 되지 않았음을 의미한다. 그래서 이동식 직화식 살균을 권하였으나 시설자재값이 감당이 안되어 엄두를 내지 못하였다. 따라서 가스버너를 도입하여 단시간에 화력을 높여 살균을 실시하므로서 세균의 증식을 막아 균사생장속도를 빠르게 하고 균사량의 축적을 높이는데 교육을 하고 컨설팅을 실시하여 개선하였다. 4. 병뚜껑과 형성틀을 대체한 링을 이용한 입봉작업시간 단축과 비용절감 버섯봉지에 배지를 담는 입봉작업을 할 때 병뚜껑과 그의 형성틀을 끼우고 솜을 조금 뜯어 톱밥배지 위에 놓는 작업을 한다. 이는 아주 잘못된 방법이다. 왜 그렇게 하는가하는 것은 이해가 간다. 그렇게 하는 이유는 접종할 때 실내에서 그냥 접종하므로 뚜껑을 열때 보호막 역할을 할 것으로 생각하고 그렇게 하는데 천만의 말이다. 어떻든 뚜껑을 열면 잡균이 들어가는 것은 마찬가지이다. 그래서 이 솜을 배지표면에 놓으면 마른 솜이 그렇지 않아도 수분이 적은데 이 솜이 수분을 또 빼앗아 가버린다. 그래서 균사생장이 늘려 15일이면 다 자라야할 균사배양기간이 한달씩 걸려도 표면만 살짝 잘린 결과가 빗어진다. 이렇게 표면만 균사가 사탕 발림식으로 자라면 품질이 저하되고 수량이 적고 병해충에 저항력이 약해지게 된다. 따라서 뚜껑과 형성틀, 솜을 모두 없애고 봉지 상단부위를 U자형으로 꺽어서 링을 끼우는 방법을 실제로 실험으로 보여준 결과 작업능률이 5배로 빠르고 작업공정이 빨라짐으로서 세균번식밀도가 적어 균사생장 속도가 2배로 빨라졌고 수량이 배가됨을 증명하고 보급하여 많은 호평을 받았다.

• Analytical Science and Technology
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• v.19 no.5
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• pp.441-448
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• 2006

11-nor-9-carboxy-${\Delta}^9$-tetrahydrocannabinol (THCCOOH) is the major metabolite of tetrahydrocannabinol (THC) which is the primary psychoactive component of marijuana. It is also the target analyte for the discrimination marijuana use. A method using solid-phase extraction (SPE) and gas chromatography/mass spectrometry (GC/MS) was developed for the determination of THCCOOH in human urine. Urine samples (3 mL) were extracted by SPE column with a cation exchange cartridge after basic hydrolysis. The eluents were then evaporated, derivatized, and injected into the GC/MS. The limits of detection (LOD) and quantitation (LOQ) were 0.4 and 1.2 ng/mL, respectively. The response was linear with a correlation coefficient of 0.999 within the concentration range of 1.2 (LLE 1.3)~50.0 ng/mL. The precision and accuracy were stable within 1.20% and the recovery was 83.6~90.7%. The recovery of SPE method was lower than that of liquid-liquid extraction (LLE), but there were no apparent differences in LOD, LOQ, precision and accuracy between the two methods. While SPE method is used as a very effective and rapid procedure for sample pretreatment, and clean extracts, LLE method was not suitable for the extraction procedure of THCCOOH in urine. The applicability of the method was proven by analyzing a urine samples from a marijuana abusers.

• Journal of the Korean Society for Marine Environment & Energy
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• v.11 no.1
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• pp.24-34
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• 2008

To mitigate the climate change and global warming, various technologies have been internationally proposed for reducing greenhouse gas emissions. Especially, in recent, carbon dioxide capture and storage (CCS) technology is regarded as one of the most promising emission reduction options that $CO_2$ be captured from major point sources (eg., power plant) and transported for storage into the marine geological structure such as deep sea saline aquifer. The purpose of this paper is to review the latest progress on the development of technologies for $CO_2$ storage in marine geological structure and its perspective in republic of Korea. To develop the technologies for $CO_2$ storage in marine geological structure, we carried out relevant R&D project, which cover the initial survey of potentially suitable marine geological structure fur $CO_2$ storage site and monitoring of the stored $CO_2$ behavior, basic design for $CO_2$ transport and storage process including onshore/offshore plant and assessment of potential environmental risk related to $CO_2$ storage in geological structure in republic of Korea. By using the results of the present researches, we can contribute to understanding not only how commercial scale (about 1 $MtCO_2$) deployment of $CO_2$ storage in the marine geological structure of East Sea, Korea, is realized but also how more reliable and safe CCS is achieved. The present study also suggests that it is possible to reduce environmental cost (about 2 trillion Won per year) with developed technology for $CO_2$ storage in marine geological structure until 2050.

• Journal of Life Science
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• v.29 no.6
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• pp.671-678
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• 2019

Antibacterial and antioxidant activities of plant sources have attracted a wide range of interest across the world over the last decade. This is due to the growing concern for safe and alternative sources of antibacterial and antioxidant agents. In this study, we focused on the antibacterial and antioxidant activities and the chemical composition of a methanol extract from Viburnum sargentii seeds. The chemical composition was determined by gas chromatography-mass spectroscopy (GC-MS), and the antibacterial activity was screened by a disc diffusion assay. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined using the microbroth dilution and spread plate method, respectively. The V. sargentii extract showed growth inhibition activity on all tested Gram-positive (Listeria monocytogenes, Staphylococcus aureus, and Staphylococcus saprophyticus) and Gram-negative (Escherichia coli, Pseudomonas putida, and Proteus vulgaris) pathogenic bacteria. The MIC and MBC ranged from 0.156~1.25 mg/ml for Gram-positive and 0.625~5.0 mg/ml for Gram-negative tested bacteria. The GC-MS results revealed the presence of several phytochemicals such as ${\beta}-sitosterol$ and vitamin E, which are known for their pharmacological applications. The antioxidant activities of V. sargentii extract were investigated by three different methods: the 2,2-diphenyl-1-picrylhydrazyl free radical scavenging assay, the reducing power assay, and the total antioxidant capacity assay. The results showed a concentration-dependent antioxidant potential for all three used methods. In sum, our findings suggest that the methanol extract of V. sargentii seeds has the potential to inhibit the growth of pathogenic bacteria and provide antioxidant compounds, making it therefore worthy of further investigation.