• Title/Summary/Keyword: extraction

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Simultaneous Analysis of Pesticide Priority Pollutants in Soil (토양 중의 Pesticide Priority Pollutants 동시 분석에 관한 연구)

  • Lee, Seung-Seok;Park, Young-Joo;Lee, Sueg-Geun
    • Analytical Science and Technology
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    • v.8 no.3
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    • pp.237-248
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    • 1995
  • The simultaneous analysis of 16 organic pesticides, which are listed as a part of 129 priority pollutants by EPA(Environmental Protection Agency), was performed by GC-ECD(electron capture detector) and GC/MS-SIM(selected ion monitoring). Two extraction procedures from SW-846, sonication extraction and Soxhlet extraction, were somewhat modified and compared as an extraction and concentration method for the analysis of priority pollutants in soil. Accuracy and precision of the methods were reported from the calculation of mean recovery, mean relative standard deviation, and method detection limit.

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Oleoresin Content and Physiological Activities of Fresh Red pepper by microwave-Assiated Extraction (마이크로웨이브 추출공정에 의한 홍고추 올레오레진의 함량 및 기능적 특성)

  • 권영주;정승원;김현구;권중호
    • Food Science and Preservation
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    • v.7 no.1
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    • pp.74-79
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    • 2000
  • Water and ethanol extracts of fresh red peppers were obtained by two methods, conventional extraction (CE) and microwave-assiated extraction (MAE), under different extraction conditions. Red pepper oleoresins extracted by CE and MAE were examined in oleoresin yield and physiological activities. The proper extraction time of MAE was about 5 minutes, whereas that of CE was 2 hours. therefore extraction time was decreased drastically by MAE but there was no significance in oleolesin yields. the electron donating abilities also showed negligible difference between two extracts obtained by CE and MAE, and 80% level in all extracts . the nitrite scavenging effect was reduced by increased of ph , and showed a high elimination effect over 85% at ph 1.2. All extracts had a high tyrosinase inhibitory effects of 100%. The angiotensin I-conventing enzyme effect showed higher activity with over 80% in MAE than 70% level in CE. the capsanthin was extracted with ethanol and was 11.4 and 12.9 ${\mu}$moles per 1 g of fresh red pepper by CE and MAE, respectively.

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Minutiae extraction using improved Binarization process of the fingerprint (지문의 개선된 이진화 과정을 통한 특징점 추출)

  • Son Won-Mu;Song Jong-Kwan;Yoon Byung-Woo;Lee Myeong-Jin
    • Journal of the Institute of Convergence Signal Processing
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    • v.5 no.4
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    • pp.243-248
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    • 2004
  • Automatic fingerprint identification is a process of direction extraction, binarization, thinning, minutiae extraction of fingerprint identification. In this process, binarization after direction extraction affects a process of thinning and minutiae extraction. The fasle binarization is increased the false minutiae extraction rate. In this paper, we proposed more exact minutiae extraction algorithm with more enhanced binarization method, compared with traditional binarization process. We could have more enhanced results by using the direction and the half distance between ridges as the threshold of binarization process. In an experiment, Fingerprint images from NIST DBI are tested and the result shows that the proposed binarization algorithm increases minutiae extraction.

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Thermodynamic Analysis of the Extraction Process and the Cold Energy Utilization of LNG (LNG추출과정과 냉열이용의 열역학적 해석)

  • Lee, G.S.;Chang, Y.S.;Ro, S.T.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.7 no.1
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    • pp.120-131
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    • 1995
  • Thermodynamic analysis of extraction process from the constant pressure LNG(Liquefied Natural Gas) vessel was performed in this study. LNG was assumed as a binary mixture of 90% methane and 10% ethane by mole fraction. The thermodynamic properties such as temperature, composition, specific volume and the amount of cold energy were predicted during extraction process. Pressure as a parameter ranges from 101.3kPa to 2000kPa. The result shows the peculiar phenomena for the LNG as a mixture. Both vapor and liquid extraction processes were investigated by a computer model. The property changes are negligible in the liquid extraction process. For the vapor extraction process, the temperature in the vessel increases rapidly and the extracted composition of methane decreases rapidly near the end of extracting process. Specific volume of vapor has the maximum and that of liquid has the minimum during the process. When pressure is increased, specific volume of vapor decreases and that of liquid increases. It was found that specific volume of vapor phase had a major effect on the heat absorption at constant pressure during vapor extraction process. If the pressure of the vessel increases, the total cold energy which can be utilized from LNG decreased.

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A STUDY HO THE PREDICTION OF DURATION OF ORTHODONTIC TREATMENT IN MALOCCLUSION (부정교합 치료기간의 예측에 관한 연구)

  • Kim, Hyuk-Jae;Lee, Dong-Joo
    • The korean journal of orthodontics
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    • v.18 no.1 s.25
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    • pp.105-112
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    • 1988
  • To predict duration of orthodontic treatment of malocclusion, 304 male and female patients whose orthodontic treatment was finished in department of orthodontics, Infirmary of dental college, Chosun University were studied. The duration of treatment was studied according to types of malocclusion, beginning ages of treatment, Hellman's dental ages, the determination of tooth extraction, types of tooth extraction and types of orthodontic appliance. The following results were obtained. 1. The duration of treatment was 18 months in Class I malocclusion, 20 months in Class II malocclusion and 24 months in Class III malocclusion. 2. The more early treatment was done, the more duration of treatment was needed according to beginning age of treatment and Hellman's dental ages. 3. Treatment of tooth extraction case was needed for 78 days more than that of non-extraction case. 4. The duration of treatment with unilateral extraction of premolars was the shortest (598 days) and that with single arch extraction of premolars was the longest (685 days) according to types of tooth extraction. 5. The duration of treatment by removable appliance was the shortest (237 days) and the combination of removable appliance, headgear and full banded appliance was the longest (1425 days) according to types of orthodontic appliance. 6. The duration of treatment was 18 months in typical orthodontic treatment with 4 extraction of premolar and full banded appliance.

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Optimization of Oil from Moringa oleifera seed using Soxhlet Extraction method

  • Ojewumi, M.E.;Oyekunle, D.T.;Emetere, M.E.;Olanipekun, O.O.
    • The Korean Journal of Food & Health Convergence
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    • v.5 no.5
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    • pp.11-25
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    • 2019
  • Extraction of oil from Moringa oleifera seed using Response Surface Methodology (RSM) was investigated. Effects of three factors namely: sample mass, particle size and extraction time on the response, Moringa oleifera a volume extracted, were determined. The Box-Behnken design of RSM was employed which resulted in 15 experimental runs. Extraction was carried out in a 250 ml Soxhlet extractor with Hexane and Ethanol as solvent. The Moringa oleifera seed powder was packed inside a muslin cloth placed in a thimble of the Soxhlet extractor. The extraction was carried out at 60℃ using thermostatic heating mantle. The solvent in the extracted oil was evaporated and the resulting oil further dried to constant weight in the oven. This study demonstrates that Moringa oleifera oil can be extracted from its seed using ethanol and acetone as extraction solvent. The optimum process variables for both solvent (ethanol and acetone) was determined at sample weight of 40 g, particle size of 325 ㎛ and extraction time of 8 hours. It can be deduced that using acetone as solvent produces a higher yield of oil at the same optimum variable conditions compared to when ethanol was used.

A Study on Extracting News Contents from News Web Pages (뉴스 웹 페이지에서 기사 본문 추출에 관한 연구)

  • Lee, Yong-Gu
    • Journal of the Korean Society for information Management
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    • v.26 no.1
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    • pp.305-320
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    • 2009
  • The news pages provided through the web contain unnecessary information. This causes low performance and inefficiency of the news processing system. In this study, news content extraction methods, which are based on sentence identification and block-level tags news web pages, was suggested. To obtain optimal performance, combinations of these methods were applied. The results showed good performance when using an extraction method which applied the sentence identification and eliminated hyperlink text from web pages. Moreover, this method showed better results when combined with the extraction method which used block-level. Extraction methods, which used sentence identification, were effective for raising the extraction recall ratio.

Changes of Soluble Solid Content in Red Pepper by Different Extraction Conditions (추출 조건에 따른 고추 수용액의 가용성 성분의 변화)

  • Lee, Hyun-Duck;Lee, Cherl-Ho
    • Journal of the Korean Society of Food Culture
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    • v.11 no.3
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    • pp.385-392
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    • 1996
  • The soluble solid of red pepper was extracted by water in order to investigate changes of soluble solid content by different extraction temperature $(4{\sim}90^{\circ}C)$ and time $(1/2{\sim}3\;hrs)$, and the contents of carotenoid, capsaicinoids, free sugar, organic acid, free amino acid in soluble solid were measured. Most of soluble solid in red pepper was extracted within the first 2 hrs and $93{\sim}98%$ of total soluble solid was extracted during the first 30 min. The contents of carotenoid increased by increasing extraction time and temperature, but decreased by increasing extraction time at $60^{\circ}C$ and $90^{\circ}C$. ${\beta}$-carotene content was sharply decreased after 2 hrs at $90^{\circ}C$. The content of capsaicinoid was sharply increased between 1 hr and 2 hr. Fructose and glucose in red pepper were extracted in the range of $83.8%{\sim}96.4%$ and the contents of free sugar gradually increased by increasing extraction time and temperature. The content of organic acid was gradually increased by increasing extraction time and temperature and the greatest amount of organic acid was extracted during the first 30 min of extraction time. The content of free amino acid was decreased by increasing extraction temperature.

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Separation of Gold and Silver from Diverse Solutions by Solvent Extraction (다양한 용액으로부터 용매추출에 의한 금과 은의 분리)

  • Xing, Weidong;Lee, Manseung
    • Resources Recycling
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    • v.26 no.5
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    • pp.3-11
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    • 2017
  • Solvent extraction is an important process to recover pure gold and silver from various leaching solutions. The present work reviews the aqueous chemistry and solvent extraction separation of gold (I, III) and silver (I) from several leaching systems such as cyanide, thiocyanate, thiosulfate, thiourea and chloride medium. The extraction and separation behavior of gold (I, III) and silver (I) by various single and mixtures was compared on the basis of extraction reaction and the selectivity from these mediums. The chloride medium is recommended for the separation of gold and silver by solvent extraction in terms of extraction and stripping efficiency.

Extraction behaviors of platinum group metals in simulated high-level liquid waste by a hydrophobic ionic liquid bearing an amino moiety

  • Wu, Hao;Kim, Seong-Yun;Takahashi, Tadayuki;Oosugi, Haruka;Ito, Tatsuya;Kanie, Kiyoshi
    • Nuclear Engineering and Technology
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    • v.53 no.4
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    • pp.1218-1223
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    • 2021
  • A hydrophobic ionic liquid including an amino moiety ([DiOcAPmim][NTf2]) was synthesized. Its extraction behaviors towards Pd(II), Ru(III), Rh(III) were investigated in nitric acid aqueous solution as a function of contact time, effect of concentration of nitric acid, effect of temperature, and effect of co-existing metal ions. The extraction kinetics of Pd(II) was fairly fast and extraction equilibrium can be attained within only 5 min under the [HNO3] = 2.05 M. When [HNO3]< 1 M, the extraction percentage of Pd(II), Ru(III), Rh(III) were all above 80%. When [HNO3] reached 2 M, all of the extraction percentage decreased and in an order of Pd(II)>Ru(III)>Rh(III). When [HNO3]> 2 M, the extraction performance gradually recovered. The effect of temperature can slightly affect the extraction performance of Pd(II). Furthermore, in simulated high-level liquid waste, [DiOcAPmim][NTf2] showed a better preference towards Pd(II) under the interference of various other co-existing metal ions.