• Title/Summary/Keyword: extraction times

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Extraction of Crude-BMP from Bovine Cortical Bone for Bone Grafts (골이식물로서의 소뼈 치밀골에서 Crude-BMP의 추출)

  • Choi Sung-jin;Park Chul;Heo Soo-young;Lee Jong-il;Jeong In-seong;Kim Nam-soo;Choi In-hyuk
    • Journal of Veterinary Clinics
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    • v.22 no.4
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    • pp.377-381
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    • 2005
  • We tried to extract bone morphogenetic protein (BMP) from the freeze-dried bovine cortical bone (FBCB) for bone graft, which were defatted with chloroform-methanol for 20 days, freeze-dried at $-80^{\circ}C$ for 7 days and sterilized by ethylene oxide gas. Two kg of FBCB were pulverized in a wheel mill to $0.5-2.0mm^3$ cubic in size. The bone particles were demineralized in 0.6N HCI for 10 days at chloroform-methanol$4^{\circ}C$ and defatted with chloroform-methanol for 6 hours at room temperature, which was going to be defatting and demineralized cortical bone (DDM). For extracting BMP, DDM was agitated continuously through 72 hours with magnetic stirrer at $4^{\circ}C$ into 12 times of volume of 6 M guanidine hydrochloride (Gdn-HCl) solution containing proteinase inhibitors to protect BMP such as 2mM N-ethylaleimide, 1mM iodoacetic acid, 1mM phenylmethylsulfonyl fluoride and a sterilizer, 1mM sodium azide. The extraction procedure was repeated for three times. All extracted solution was centrifuged at 10,000 rpm for 30 min and then, the supernatant was dialyzed with 12 times of volume of deionized water at $4^{\circ}C$ for 24-72 hours, which cut off below 6,000-8,000 molecular weight. The dialyzed specimen contained crude-BMP was centrifuged, freeze-dried, and weighted. Through these processing, we could obtained $84.9\%$ as FBCB, $17.8\%$ as DDM and $0.71\%$ as crude-BMP from the wet cortical bone without cancellous bone, marrow and muscles. The crude-BMP were obtained $68.3\%$ from the first extraction, $29.6\%$ from secondary and $2.1\%$ from tertiary, respectively. It was suggested that high yield of crude-BMP migth be explained by three-time repetition of the extraction processing for crude-BMP with Gdn-Hcl sol.

Comparison of finite element analysis of the closing patterns between first and second premolar extraction spaces (상악 제1 및 제2소구치의 발치공간 폐쇄기전에 대한 3차원 유한요소 해석의 비교 연구)

  • Koh, Shin-Ae;Im, Won-Hee;Park, Sun-Hyung;Chun, Youn-Sic
    • The korean journal of orthodontics
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    • v.37 no.6
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    • pp.407-420
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    • 2007
  • The aim of this study was to compare the differences in closing extraction spaces between maxillary first premolar and second premolar extractions using 3-dimensional finite element analysis (FEA). Methods: Maxillary artificial teeth were selected according to Wheeler's dental anatomy. The size and shape of each tooth, bracket and archwire were made from captured real images by a 3D laser scanner and FEA was performed with a 10-noded tetrahedron. A $10^{\circ}$ gable bend was placed behind the bull loop on a $0.017"{\times}0.025"$ archwire. The extraction space was then closed through 12 repeated activating processes for each 2mm of space. Results and Conclusions: The study demonstrated that the retraction of anterior teeth was less for the second premolar extraction than for the first premolar extraction. The anterior teeth showed a controlled tipping movement with slight extrusion, and the posterior teeth showed a mesial-in rotational movement. For the second premolar extraction, buccal movement of posterior teeth was highly increased.

Extraction Behaviour of Np with DEHPA from the Low Nitric Acid Solution Containing Hydrogen Peroxide (과산화수소가 함유된 저산도 질산용액에서 DEHPA 추출제에 의한 Np의 추출거동)

  • Lee, E.H.;Yang, H.B.;Kim, K.K.;Lim, J.K.;Yoo, J.H.
    • Applied Chemistry for Engineering
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    • v.7 no.4
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    • pp.707-714
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    • 1996
  • Extraction behaviour of Np with DEHPA(di-(2-ethyhexyl)Phosphoric acid) from the low nitric acid solution(below 1M $HNO_3$) containing $H_2O_2$ as a reducing agent was studied at a batch system in order to establish the conditions of extraction and stripping and to enhance the extraction rate. As results, it was confirmed that the Np was mainly the pentavalent oxidation state in the low nitric acid solution. The extraction yield of Np was increased with increasing the concentration of DEHPA and $H_2O_2$ and decreased more rapidly with the increase of $HNO_3$ concentration. It was also found that the Np could be extracted into DEHPA even without the addiction any redox agents, although the extraction yield is rather low as about 70%. The extraction rate was proportional to the 0.516 power of $H_2O_2$ concentration and inversely proportional to 0.483 power of $HNO_3$ concentration as follows. $d[Np(V)]/dt=-1.391{\times}10^{-2}[H_2O_2]^{0.516}[HNO_3]^{-0.483}[Np(V)]$ Regardless of the $H_2O_2$, the Np extracted in the organic phase was effectively stripped to the aqueous phase with $H_2C_2O_4$. The Np could be stripped more than 92 % with 0.5M $H_2C_2O_4$.

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Comparison of Analytical Methods for DEHP Migration from PVC Bags for Blood Storage and Infusion; By Gas Chromatography and UV-vis Spectrophotometry (혈액·수액용 PVC 백에서 용출된 DEHP의 검출 분석 방법 비교; 기체 크로마토그래프와 분광 광도계)

  • Kim, Jung Hwan;Kim, Seong Hun;Choi, Hyeong Ki;Lee, Chang Hyung
    • Analytical Science and Technology
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    • v.15 no.1
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    • pp.72-79
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    • 2002
  • Di-(2-ethylhexyl)phthalate (DEHP) may be released from plasticized poly(vinyl chloride) (PVC) articles. In the cases of various methods for the quantitative analysis of migrating DEHP, there are much differences in migrating quantity according to the experimental methods. It is therefore important to make the comparison and analysis between these two results. A study of DEHP migration from blood and infusion bags has been carried out in different methods to evaluate the amount of DEHP migration using gas chromatograph and UV-vis spectrophotometry. Five PVC bags were cut into plane sheets in size of $40{\times}10{\times}0.4mm$, then were immersed in extraction solvent for an hour to release DEHP. It was determined by a gas chromatograph that $23.2{\sim}70.9{\mu}g/mL$ of DEHP was extracted. While extraction solvent was injected into PVC bags which were then placed for an hour to leach DEHP out. It was checked by a UV-vis spectrophotometer that the concentration of DEHP in extraction solvent was $24.8{\sim}41.3{\mu}g/mL$. Two results show different values according to the extraction conditions and experimental methods and the gas chromatographic results were converted into UV-vis spectroscopic results on condition that DEHP would be extracted equally per unit time and unit contact area. It was concluded that DEHP migrating amounts are approximately equal in two analytical methods.

Water body extraction using block-based image partitioning and extension of water body boundaries (블록 기반의 영상 분할과 수계 경계의 확장을 이용한 수계 검출)

  • Ye, Chul-Soo
    • Korean Journal of Remote Sensing
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    • v.32 no.5
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    • pp.471-482
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    • 2016
  • This paper presents an extraction method for water body which uses block-based image partitioning and extension of water body boundaries to improve the performance of supervised classification for water body extraction. The Mahalanobis distance image is created by computing the spectral information of Normalized Difference Water Index (NDWI) and Near Infrared (NIR) band images over a training site within the water body in order to extract an initial water body area. To reduce the effect of noise contained in the Mahalanobis distance image, we apply mean curvature diffusion to the image, which controls diffusion coefficients based on connectivity strength between adjacent pixels and then extract the initial water body area. After partitioning the extracted water body image into the non-overlapping blocks of same size, we update the water body area using the information of water body belonging to water body boundaries. The update is performed repeatedly under the condition that the statistical distance between water body area belonging to water body boundaries and the training site is not greater than a threshold value. The accuracy assessment of the proposed algorithm was tested using KOMPSAT-2 images for the various block sizes between $11{\times}11$ and $19{\times}19$. The overall accuracy and Kappa coefficient of the algorithm varied from 99.47% to 99.53% and from 95.07% to 95.80%, respectively.

Chloride Extraction and Modified Structural Behavior of Concrete under Electrochemical Treatment (전기방식에 따른 콘크리트 중의 탈염효과 및 구조거동)

  • Ann, Ki-Yong;Kim, Ki-Beom;Yang, Hee-Jun
    • Journal of the Korea Concrete Institute
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    • v.29 no.1
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    • pp.109-116
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    • 2017
  • The present study concerns quantitative assessment of chloride extraction, repassivation and structural behavior of concrete. Concrete specimen ($160{\times}160{\times}1000mm$) was fabricated with 3 steel bar located in the middle with 20 mm of the cover depth, containing 5.0% of chloride to accelerate corrosion process, then to be subjected to electrochemical treatment. The current density accounted for $750mA/m^2$ at 2, 4 and 8 weeks. As a result, it was found that an increase in the duration of the treatment resulted in an increase in the chloride extraction, accounting for 64.7-83.7% for the specimen at 8 weeks treatment. It implies that a portion of bound chlorides would turn free to be removed, considering the binding capacity of cement about 50-60% to total ones. Even after the treatment, the corrosion was still active; the corrosion rate was $6.5mA/m^2$ and 330 mV vs. SCE in the potential. For structural behavior, the maximum load was increased by corrosion on the steel bars, which was subsequently lowered by the treatment, but still higher than for control.

Lutein, β-Carotene, and Polyphenol Contents of Sweet Potato Leaves under Different Extraction Conditions (추출조건에 따른 고구마 잎의 Lutein, β-Carotene 및 Polyphenol 함량)

  • Li, Meishan;Jang, Gwi Yeong;Lee, Sang Hoon;Hwang, Se Gu;Sin, Hyun Man;Kim, Hong Sig;Lee, Junsoo;Jeong, Heon Sang
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.46 no.11
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    • pp.1343-1349
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    • 2017
  • This study was carried out to determine the simultaneous extraction conditions of functional components (lutein, ${\beta}$-carotene, total polyphenol, flavonoids, and phenolic compounds) from sweet potato leaves and to evaluate the antioxidant activities. Extraction conditions included different ethanol concentrations (1st extraction: 99.9% ethanol; 2nd extraction: 50~90% ethanol) and times (30, 60, and 90 min). The highest values of lutein and ${\beta}$-carotene content were obtained by the 2nd extraction at an ethanol concentration of 90%. The extraction yields of lutein and ${\beta}$-carotene decreased with increasing extraction time. The maximum polyphenol, flavonoid, and total phenolic acid contents and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) and 1,1-diphenyl-2-picrylhydrazyl radical scavenging activities were 32.3 mg gallic acid equivalent/g, 17.0 mg catechin equivalent/g, 2,842.6 mg/100 g, 17.0 mg ascorbic acid equivalent/g, and 1.94 mg/mL ($IC_{50}$) at the 2nd extraction with an ethanol concentration of 60%. The optimum extraction conditions were as follows; ethanol concentrations of the extraction solvent were 99.9% (1st extraction) and 60% (2nd extraction), and extraction time was 30 min.

3D Line Segment Extraction Based on Line Fitting of Elevation Data

  • Woo, Dong-Min
    • Journal of IKEEE
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    • v.13 no.2
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    • pp.181-185
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    • 2009
  • In this paper, we are concerned with a 3D line segment extraction method by area-based stereo matching technique. The main idea is based on line fitting of elevation data on 2D line coordinates of ortho-image. Elevation data and ortho-image can be obtained by well-known area-based stereo matching technique. In order to use elevation in line fitting, the elevation itself should be reliable. To measure the reliability of elevation, in this paper, we employ the concept of self-consistency. We test the effectiveness of the proposed method with a quantitative accuracy analysis using synthetic images generated from Avenches data set of Ascona aerial images. Experimental results indicate that our method generates 3D line segments almost 7.5 times more accurate than raw elevations obtained by area-based method.

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Determination of Chlorpromazine Using Plasticizers as Extraction Solvent (가소제를 이용한 클로르프로마진의 용매 추출 분광광도법)

  • Lee, Ji-Yeoun;Jung, Moon-Mo;Hur, Moon-Hye;Ahn, Moon-Kyu
    • YAKHAK HOEJI
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    • v.42 no.3
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    • pp.243-247
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    • 1998
  • A method for the determination of basic drugs based on their reaction with picric acid to form an ion-association complex extractable into several plasticizers was developed. Ba sic drugs-picric acid complexes in acid medium could be extracted quantitatively into several plasticizers except phosphates. For example, the chlorpromazine-picric acid complex showed maximum absorbance at near 410nm and was applied to extraction spectrophotometric determination of chlorpromazine. The calibration curves are linear (r>0.998) within a range from $10^{-6}to\;5{\times}10^{-4}M$ and the precision of the method was acceptable because RSD was less than 2.6% (n=7). The factors affecting the extraction system was discussed.

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Studies on the Characteristics of Humic Acid and its Utilizations (I) (土炭 흄酸의 性狀 및 應用에 關한 硏究 (I) 흄酸의 溶出 및 그 條件에 따른 흄酸性狀의 變異)

  • Kim, Won-Taik
    • Journal of the Korean Chemical Society
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    • v.12 no.4
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    • pp.155-159
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    • 1968
  • On the extraction of humic acid from peat, the optimum conditions were studied and the effects of them on the characteristics of humic acid were also examined by means of infrared spectroscopy. 1. Pretreatment of peat with diluted 6-8% HCl solution for 5 hrs. prior to extraction with alcohol-benzol azeotropic mixture have resulted the better yield of humic acid. The water soluble Na-humates were obtained by the subsequent extraction with one hundred times quantity of caustic soda solutieon for 1hr. at 90 $^{\circ}C$. Thus the pure humic acids have been yielded approximately 40% (by wt.) from the raw peat. 2. In characteristics of humic acid, the chemical structure, mainly the contents of such functional groups as -COOH, -OH (phenol type), $-CH_2CO-$, $-CH_2{\cdot}O{\cdot}CH_2-$ and aromatic rings were varied according to the concentration of alkaline solution, temperature and time when the humic acids were extracted with alkali.

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