• Environmental Analysis Health and Toxicology
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• 제22권1호
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• pp.49-55
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• 2007

Three kind of ASE (Accelerated Solvent Extraction) and SPMDs (Semi-Permeable Membrane Devices) combined methods (ASE-SPMDs, ASE-accelerated SPMDs and SPMDs without extraction) and general Soxhlet-GPC were compared each other for the analysis of PCDD/FS in sediment. The average recovery rate of three types ASE and SPMDs combined methods (108.1%) were higher than that of the Soxhlet-GPC (79.5%) for three samples in each method using surrogate internal standards. The average coefficient of variation (10%, $2.1{\sim}25.2%$) for each congener of PCDD/Fs shows the reasonable results. Total PCDD/Fs concentrations after SPMDs without extraction were quite low, but those after ASE-SPMDs and ASE-accelerated SPMDs methods were close to the Soxhlet-GPC. Thus, the ASE-SPMDs and ASE-accelerated SPMDs methods are considered as the excellent pre-treatments method because they need less solvent and time without quality degradation.

• 한국작물학회지
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• 제44권2호
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• pp.154-158
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• 1999

Volatile flavor compounds from perilla leaves were extracted and analyzed with different methods, head-space analysis (HS), simultaneous steam distillation and extraction (SDE) , and solvent extraction (SE), and to compare their efficiencies for quick analysis. Over 30 volatile compounds were isolated and 28 compounds were identified by GC/MSD. Major compound was perillaketone showing the compositions of which were 92% in SDE method, 86% in headspace analysis, and 62% in solvent extraction method. For quick evaluation of leaf flavor in perilla, it was desirable because the headspace analysis method had a shorter analyzing time and smaller sample amount than the other methods.

• 한국지하수토양환경학회지:지하수토양환경
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• 제19권3호
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• pp.15-24
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• 2014

Soil pollution has been recognized as a serious problem because it causes groundwater pollution through medium contacts. Although concentration of individual chemical could be more easily measured by physico-chemical analysis, it is not easy to consider the bioavailability of edaphic receptors living in soil or groundwater. To measure the toxicity of soil, the soil extracts (soil elutriates or soil suspensions in the other words) are often used due to the difficulties of extracting soil pore water. In this study, we reviewed 15 toxicity test methods found in literature to analyze the detail of each extraction method and to recommend the most frequently used extraction methods. The identified most commonly used extraction methods are as following: The 1 : 4 soil:water ratio, 24 hours shaking time, room temperature, dark, and separation of supernatant using a $0.45{\mu}m$ pore size filter.

• 대한한의학원전학회지
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• 제32권3호
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• pp.47-57
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• 2019

Objectives : We aim to assist in choosing an appropriate method for word extraction when analyzing East Asian Traditional Medical texts based on unsupervised learning. Methods : In order to assign ranks to substrings, we conducted a test using one method(BE:Branching Entropy) for exterior boundary value, three methods(CS:cohesion score, TS:t-score, SL:simple-ll) for interior boundary value, and six methods(BExSL, BExTS, BExCS, CSxTS, CSxSL, TSxSL) from combining them. Results : When Miss Rate(MR) was used as the criterion, the error was minimal when the TS and SL were used together, while the error was maximum when CS was used alone. When number of segmented texts was applied as weight value, the results were the best in the case of SL, and the worst in the case of BE alone. Conclusions : Unsupervised-Learning-Based Word Extraction is a method that can be used to analyze texts without a prepared set of vocabulary data. When using this method, SL or the combination of SL and TS could be considered primarily.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.2
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• pp.465-469
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• 2006

Pre-treatment methods to determine various heavy metal contents in packaging papers were investigated by ICP-ES (Inductively Coupled Plasma Emission Spectrometry) analysis. Pre-treatment methods utilized in this study include dry ashing and decomposition methods ($HNO_{3-}HClO_{4-}HF,\;HNO_{3},\;and\;H_{2}SO_{4-}HNO_{3}$). They were compared with the conventional extraction (water) and migration (3% acetic acid) methods. The five representative heavy metals (Cd, As, Pb, Cr and Hg) were analyzed. For Cd, Hg, and As, the results were below detection limit of the instrument. In case of Cr and Pb, the migration test is considered to be a better method compared to the extraction test, but all pretreated methods showed much higher detection efficiency than the extraction or migration test. However, the detection ratio between the migration test and decomposition methods was different. Among all decomposition methods, the nitric acid - perchloric acid - hydrofluoric acid treatment brought a slightly higher detection value than others, but there was no significant difference among them except sulfuric acid - nitric acid method. Concerning Pb, the sulfuric acid - nitric acid method showed a low detection efficiency compared to other decomposition methods. The sulfuric acid - nitric acid method is, thus, not considered to be a suitable analysis method for Pb in packaging papers.

• 한국토양동물학회지
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• 제5권2호
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• pp.63-70
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• 2000

영국의 고원지대 (Moorland)의 이탄토양 (blanket bog peat soil에 서식하는 애지렁이 정량조사를 위한 수분갈때기추출법의 효율에 미치는 수온, 물의 량, 추출시간의 복합적인 효과를 조사하였다. 이탄 토양에서 애지렁이 추출을 위한 최적조건은 물의 양과 초기 수온에 관계없이 표면수의 최종 온도는 35$^{\circ}C$이고, 추출시간은 6시간이었다. O'Connor의 방법 (최종 온도 40-45$^{\circ}C$,열의 점진적인 증가, 3시간 추출)은 비교적 늪은 온도와 짧은 추출시간으로 인해, 추출효율에 변이가 심하였다. 열을 가하지 않고 장시간 추출하는 방식은 열을 가하는 방식에 비해 추출효율이 현저히 낮았다.

• 한국식품저장유통학회지
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• 제12권2호
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• pp.146-150
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• 2005

오가피(Acanthopanax senticosus)로부터 영양 및 기능성 성분의 열수추출 수율을 증대시킬 수 있는 방법을 개발하기 위하여 추출 전처리 및 방법의 효과를 검토하였다. 오가피를 분쇄, 체질$(8\~20\;mesh)$하고 초음파(20 kHz), 마이크로파 (2,450 MHz) 또는 볶음$(180^{\circ}C)$ 처리를 10분 동안 실시한 후 물을 용매로 상압$(100^{\circ}C)$ 추출과 가압$(121^{\circ}C)$ 추출을 각각 2시간 동안 실시하였다. 전반적으로 전처리는 성분들의 추출수율과 유리기 소거능을 증가 시키는 경향을 보였다. 특히, 가용성 고형물, 총당 및 페놀성 물질의 추출수율은 마이크로파와 초음파에 의해, 단백질의 추출수율과 유리기 소거능은 볶음처리에 의해 더욱 증가됨을 보였다. 상압추출보다 가압추출에 의해 가용성 고형물, 총당, 단백질 및 페놀성 물질의 추출수율이 증대되는 경향을 보였다. 이로써 초음파, 마이크로파 및 볶음 전처리 및 가압추출은 오가피의 추출효율 향상에 유효한 방법인 것으로 판단된다.

• Journal of Ginseng Research
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• 제13권2호
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• pp.198-201
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• 1989

백삼의 주요 polyacetylene 성분인 panaxynol과 panaxydol을 capillary-GC(FID)로 정량하고 몇 가지 추출용매(석유 ether, dichloromethane, ether, ethyl acetate, acetone, acetonitrile and methanol) 및 추출방법(진탕추출, Soxhlet 추출 또는 환류추출)에 따른 이들 성분의 추출율을 비교하였다. 이 때, GC column은 SPB-1 fused silica capillary (0.25 mm id $\times$30 m, Supelco)를 사용하였고, column oven 의 온도는 $200^{\circ}C$에서 $300^{\circ}C$까지 분단 $4^{\circ}C$씩 승온하였다. 추출용매에 따른 panaxynol과 panaxydol의 추출율은 methanol 에 의하여 환류추출하는 방법이 백삼 중 polyacetylene 성분을 최대로 추출하는 조건인 것으로 사료되었는데, 이 추출방법에 의하여 얻어진 4년근 백삼시료의 panaxynol과 panaxydol의 함량분석값은 각각 4.2mg/g과 6.4mg/g이었다.

• 한국약용작물학회지
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• 제17권6호
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• pp.427-433
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• 2009

Volatile flavor compounds from the shoot and root of Angelica gigas Nakai were extracted by HE (Hydrodistillation extraction), SDE (Simultaneous steam distillation & extraction), and SFE (Supercritical fluid extraction system), and analyzed by GC-MS. The amount and the number of chemical components in essential oils from shoot and root by SFE was the higher than those by other extraction methods. Respectively, thirty one constituents were identified from the essential oil of the shoot and root by HE, twenty seven and twenty three constituents were identified from the essential oil of shoot and root by SDE, thirty one and forty five constituents were identified from the essential oil of shoot and root by SFE. The result showed large differences in extraction methods and in plant parts of Angelica gigas Nakai. Also, the bioactive compounds in root part was identified as nodakenin and decursinol (11.95% and 8.42%, respectively) by SFE. These results suggested that SFE was the best extraction method for the increasing of extraction yield, the determination of volatile components and the increasing of bioactive compounds in the shoot and root of Angelica gigas Nakai.

• 분석과학
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• 제17권4호
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• pp.289-294
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• 2004

고성능 액체 크로마토그래피를 이용하여 고삼 중의 oxymatrine을 분석하였다. acetonitrile을 포함하는 완충용액과 $C_{18}$컬럼을 이용한 역상 크로마토그래피를 수행하였다. Oxymatrine의 분리는 215 nm에서 UV흡수가 관측되었다. 고삼 중의 oxymatrine의 추출은 다양한 용매와 다양한 추출방법을 사용한 결과, 마쇄한 고삼의 최적의 추출 효율은 $80^{\circ}C$에서 50% ethanol로 5시간 동안 환류가열 하였을 때 가장 높은 효율을 보였다. 대부분의 추출 방법은 복잡한 전처리를 필요로 하지만, 본 연구에서는 승화 추출법으로 복잡한 전처리를 제외시킨 추출법을 고안하였다. 승화 추출은 높은 진공 ($1{\times}10^{-3}$ torr) 과 높은 온도 ($200^{\circ}C$)에서 수행되었다. 승화 추출법을 사용한 추출 효율은 다른 추출 방법들과 비교해서 전처리 과정을 거치지 않은 장점은 있었으나 추출 효율이 좀 낮았다.