• 한국해양바이오학회지
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• 제2권1호
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• pp.55-59
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• 2007

The oil and concentrated protein powder from squid viscera was extracted and recovered by a semi-batch supercritical carbon dioxide ($SCO_2$) extraction system and the degree of oxidation in the extracted oil was measured in order to compare with extracted oils using organic solvents. The degree of storage in treated squid viscera by $SCO_2$ extraction was measured in order to compare with untreated squid viscera. As results obtained, it was found that the auto-oxidation of the oils using $SCO_2$ extraction occurred very slowly compared to the oils by organic solvent extraction. And the treated squid viscera by $SCO_2$ extraction was reached the point of initial rottenness slowly than untreated squid viscera.

• Journal of Plant Biology
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• 제19권4호
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• pp.95-99
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• 1976

This work deals with different extraction media and reaction mixtures on photosystem II activity of Spinach chloroplasts. The photoreduction rate of ferricyanide and DPIP by intact chloroplasts which extracted with four kinds of extraction media; S-Tris-N pH 7.2, 8.0, S-Tricine-N pH 7.2, 8.0, was measured in five kinds of reaction mixtures; S-Tris-N pH 7.2, 8.0, S-Tricine-N pH 7.2, 8.0, 0.05 M-Tris pH 7.2. The extraction medium which shows the highest photoreduction rate was S-Tris-N at pH 7.2 and S-Tricine-N at pH 8.0. As to the reaciton mixture, S-Tricine-N pH 8.0 showed the highest rate. On the complex effects of extraction media and reaction mixtures, the highest photordeuction rate of Hill oxidant by intact chloroplasts was obtained by S-Tris-N pH 7.2 extraction medium and S-Tricine-N pH 8.0 reaction mixture. The second highest activity was obtained by S-Tricine-N pH 8.0 extraction medium and reaction mixture.

• 한국의류학회지
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• 제27권11호
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• pp.1350-1357
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• 2003

This research was aimed to establish the standard extraction and analytical procedures for examining the chromophoric substance in madder root with the ultimate goal of identifying the dyes in badly faded textiles of archaeological origin. The separation temperature of gas chromatography, pH and other extraction conditions were tested. The results were as follows: The suitable separation temperature for the GC cappillary column was 50∼305$^{\circ}C$, and methanol was a good GC solvent for both standard alizarin and madder extraction. The best extraction of madder was achieved by 90 min soaking in room temperature followed by filtration and the actual heat extraction procedure. The best pH for extracting alizarin was pH 3 and above pH 5 alizarin was not detectible. Only alizarin and no purpurin was found in the extraction of the currently used madder plant.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 임시총회 및 추계학술발표회
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• pp.227-230
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• 2004

Two extraction techniques, Ultrasonic and Microwave extraction method, were tested for the determination of arsenic in contaminated soil SRM (Montana Soil). The extraction mixture was prepared by mixing 1 M ortho-phosphoric acid and 0.1 M ascorbic acid. This extractant was known to preserve arsenic species. The appropriate extraction time was 10 min to 20 min and the recovery rate was about 80%. A coupled system, SPE-HG-ICP-AES, was used for the determination of inorganic arsenic species. The detection limit was around 2 $\mu\textrm{g}$/1 and the linearity of calibration curve was better than $R^2$=0.99.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2003년도 International Symposium on Clean Environment
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• pp.135-138
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• 2003

Based on solid phase extraction, gas chromatography and mass spectrometry procedure for determining phenol and its derivatives in natural water was presented. In solid phase extraction, three types of techniques using solid phase adsorption material were treated with acid and salt, and converted second portion of acetyl derivatives. Under the these condition, extraction efficiency and detection ability dependent on extraction methods were discussed. Obtained results using optimized solid phase extraction techniques showed more convenience, simplifier and lower cost than the conventional analytical methods with holding wide dynamic range and lower detection limits.

• Journal of Information Processing Systems
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• 제8권4호
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• pp.693-712
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• 2012

The paper presents three machine learning based keyphrase extraction methods that respectively use Decision Trees, Na$\ddot{i}$ve Bayes, and Artificial Neural Networks for keyphrase extraction. We consider keyphrases as being phrases that consist of one or more words and as representing the important concepts in a text document. The three machine learning based keyphrase extraction methods that we use for experimentation have been compared with a publicly available keyphrase extraction system called KEA. The experimental results show that the Neural Network based keyphrase extraction method outperforms two other keyphrase extraction methods that use the Decision Tree and Na$\ddot{i}$ve Bayes. The results also show that the Neural Network based method performs better than KEA.

• 자원리싸이클링
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• 제15권4호
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• pp.13-18
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• 2006

본 연구는 Gd 용액을 대상으로 추출시간, 평형 pH와 초기농도의 변화를 통하여 HEH/EHP를 함유한 추출수지의 추출특성을 파악하고자 하였다. 추출수지를 사용하여 Gd을 추출시 추출시간은 90분 정도가 적절한 것으로 판단된다. 추출율(%)은 평형 pH $1.0{\sim}2.0$ 사이에서 평형 pH가 증가할수록 증가하였다. 평형에서 Freundlich 흡착등온식을 사용하여 계산된 측정값과 예측값이 잘 일치하였다.

• 자원리싸이클링
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• 제27권4호
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• pp.65-69
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• 2018

용매추출에서 등온추출곡선은 수상과 유기상에서 평형관계에 있는 농도를 나타낸다. 등온추출곡선과 조업선을 동시에 나타낸 McCabe-Thiele도는 물질 전달공정에서 여러 유용한 정보를 제공한다. 추출반응식과 평형상수를 알고 있는 경우 등온추출곡선을 계산으로 구하는 방법을 소개하였다. 또한 분배계수가 일정한 경우 금속 추출에 필요한 추출단수를 추산할 수 있는 Kresmer식을 소개하였다.

• 한국식품과학회지
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• 제35권6호
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• pp.1104-1109
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• 2003

초임계 이산화탄소를 이용하여 감귤박으로부터 ${\beta}$-cryptoxanthin을 포함한 carotenoids의 추출수율을 극대화하기 위하여, 주요 요인 변수인 추출 압력, 추출시간, 보조용매의 농도 등 추출 조건을 반응표면분석법에 의해 최적화하였다. Total carotenoids와 ${\beta}$-cryptoxanthin의 추출수율에 대한 반응표면 회귀방정식의 $R^2$는 각각 0.9789과 0.9796이었고, 1% 이내의 수준에서 유의성이 인정되었다. 추출조건에 따라 예측된 정상점은 안장점이었으며 능선분석을 실시한 결과 total carotenoids과 ${\beta}$-cryptoxanthin의 최대 추출수율은 각각 61.1%와 95.8%로 예측되었으며, 이 때의 추출 압력, 추출시간, ethanol의 농도는 각각 33.4MPa/39.6min/18.6%와 37.3 MPa/41.0 min/17.0%이었다. Total carotenoids의 추출수율은 추출 압력의 증가에 따라 증가하였지만 압력이 높을수록 일정한 값에 도달하는 경향을 보인 반면, 추출시간과 보조용매의 농도 증가에 따라 연속적으로 증가하였다. ${\beta}-Cryptoxanthin$의 추출수율은 추출 압력, 추출시간, 보조용매의 농도 증가에 따라 연속적으로 증가하였다. 감귤박으로부터 carotenoids의 추출에는 추출시간과 보조용매의 농도 사이의 상호작용이 중요한 역할을 하였다.

• 폴리머
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• 제32권1호
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• pp.13-18
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• 2008

전기 전자재료 중 고분자에 포함된 브롬계 난연제의 분석에 있어 용출이 어려운 4가지 재질 PC(polycar-bonate) PP(polypropylene), PET(poly(ethylene terephthalate)), PBT(poly(butylene terephthalate))에 대하여 추출방법 및 헥산/에세톤, THF, 톨루엔, THF/톨루엔에 대한 용매 특이성과 그 특성을 고찰하였다. 각 고분자에서의 deca-BDE(decabromo diphenyl ether)의 함량을 속슬렛, 초음파. 가속용매, 마이크로파, 초임계 유체 추출법을 사용하여 이들 방법의 효율을 정량분석 하였다. 초음파 추출은 낮은 고분자의 용해도 때문에 낮은 추출효율을 보여 사용한 고분자의 경우에 있어서 추출방법으로는 적합하지 않았으며, 나머지 3가지 방법에서는 톨루엔 사용시 약 80% 이상의 높은 추출효율을 보였다. 초임계 유체 추출은 고분자의 난연제 추출에 시도되지 않았던 방법이었으나, 본 실험에서 PP와 PC의 추출에서는 100%에 가까운 매우 높은 추출효율을 보였다.