• 제목/요약/키워드: Capillary limit

검색결과 76건 처리시간 0.026초

식육중 Chlorfluazuron의 잔류분석법 및 잔류량에 관한 연구 (Studies on the Analytical Methods and Quantity of Residual Chlorfluazuron in Meat)

  • 박건상;홍무기;백선영;정병곤;박종세
    • 한국식품위생안전성학회지
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    • 제12권4호
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    • pp.288-293
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    • 1997
  • Analytical method using capillary GC/ECD was developed to determine trace residues of chlofluazuron, 1-[3, 5-dichloro-5-trifluoromethyl-2-pyridyloxy)phenyl]-3-(2, 6-difiuorobenzoyl), in meat, and applied to analyze the residues in domestic and imported meats. The analytical scheme developed does not require column chromatographic cleanup; chlorfiuazuron was extracted with diethyl ether and petroleum ether (50: 50), partitioned against acetonitrile, cleaned up with silica Sep-Pak cartridge, identified GC/ECD, and comfirmed by GC/MS. The mean recoveries of the pesticide in meat fortified with standard solution 0.1, 0.5, 0.1 mg/kg were ranged from 82 to 95%. The limit of detection and limit of quantitation were 0.001 and 0.005 mg/kg, respectively. Chlorfluazuron residues were not found in domestic samples, but found in imported Australian beef ranging from 0.02 to 0.17 mg/kg, detected by 18% among the samples.

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소결 금속 윅 히트파이프 개발을 위한 제조 기술 연구 (A Study on the Manufacturing Technology for the Development of Heat Pipes with a Sintered Metal Wick)

  • 최지훈;김성대;성병호;유성열;박형기;김철주;고한서
    • 유체기계공업학회:학술대회논문집
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    • 유체기계공업학회 2006년 제4회 한국유체공학학술대회 논문집
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    • pp.479-482
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    • 2006
  • The most the electronic industry has recently accelerated the modularization, the miniaturization and the high integrated trend of electronics fields such as electronics components, appliances and etc., the most increasingly the heat generation problem rises. Even though the conventional cooling technologies are widely used in order to reduce the heat loads, the technologies are not easy to meet the present trends due to the fact that most of many conventional methods are relative to external form environments such as size, design and so on. With regardless of those environments, however, a heat pipe is one of the most efficient systems to improve the heat transfer performance. And then the performance of the heat pipe depends on a wick structure. Of various wick structures, sintered metal wick is known so that it has some advantages such as smaller pore size, increasing porosity as well as high reliability. In this study sintered metal wicks, thickness 0.7 mm, 0.8 mm and 0.9 mm, were manufactured as of $100{\mu}m$ copper powder to obtain the manufacturing technology of heat pipes mounted with a sintered metal wick. Furthermore, experiments for the operational performance factors such as capillary limit, thermal resistance were not only performed but also compared with a theoretical model simultaneously. Experimental results agreed with the theoretical model, and then it seems to be required to study various development processes of sintered metal wicks for the high performance of a heat pipe system.

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Chiral Purity Test of Bevantolol by Capillaryelectrophoresis and High Performance Liquid Chromatography

  • Long, Pham Hai;Trung, Tran Quoc;Oh, Joung-Won;Kim, Kyeong-Ho
    • Archives of Pharmacal Research
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    • 제29권9호
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    • pp.808-813
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    • 2006
  • Two methods for the chiral purity determination of bevantolol were developed, namely capillary electrophoresis (CE) using carboxymethyl-${\beta}$-cyclodextrin (CM-${\beta}$-CD) as a chiral selector and high-perfomance liquid chromatography (HPLC) using a chiral stationary phase. In the HPLC method, the separation of bevantolol enantiomers was performed on a Chiralpak AD-H column by isocratic elution with n-hexane-ethanol-diethylamine (10:90:0.1, v/v/v) as mobile phase. In the CE method, bevantolol enantiomers were separated on an uncoated fused silica capillary with 50 mM amonium phosphate dibasic adjusted to a pH 6.5 with phosphoric acid containing 15 mM CM-${\beta}$-CD as running buffer. Validation data such as linearity, recovery, detection limit, and precision of the two methods are presented. The detection limits of S-(-)-bevantolol were 0.1% and 0.05% for CE and HPLC method, respectively and R-(+)-bevantolol were 0.15% and 0.05% for CE and HPLC method, respectively. There was generally good agreement between the HPLC and CE results.

Capillary Size-exclusion Chromatography as a Gel-free Strategy in Plasma Proteomics

  • Cho, Man-Ho;Wishnok, John S.;Tannenbaum, Steven R.
    • Molecular & Cellular Toxicology
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    • 제1권2호
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    • pp.87-91
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    • 2005
  • Although 2D-PAGE has been widely used as the primary method for protein separation, difficulties in displaying proteins with an extreme values of isoelectric paint (pI), molecular size and hydrophobicity limit the technique. In addition, time consuming steps involving protein transfer and extraction from the gel-pieces can result in sample loss. Here, we describe a novel protein separation technique with capillary size-exclusion chromatography (CSEC) for rapid protein identification from human plasma. The method includes protein fractionation along with molecular size followed by in-solution tryptic digestion and peptide analysis through reversed phase liquid chromatography (RPLC) coupled to nanoflow electrospray-tandem mass spectrometry (ESI-MS/MS). Tryptic peptides are applied an a $100\;{\mu}m\;i.d.{\times}10mm$ length pre-column and then separated on a $75\;{\mu}m{\times}200mm$ analytical column at -100 nL/min flaw rate. Proteins were identified over the wide ranges of pI (3.7-12.3) when this technique was applied to the analysis of $1-2\;{\mu}L$ of human plasma. This gel-free system provides fast fractionation and may be considered a complementary technique to SDS-PAGE in proteomics.

어유혼합경유의 균일액상 생성영역에 관한 실험적 연구 (An Experimental Study on the Uniform Droplet Production Regions of Light Oil Blended with Fish Oil)

  • 장재은;안수길
    • 수산해양기술연구
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    • 제28권2호
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    • pp.164-170
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    • 1992
  • In order to understand and explain the spary combustion, it was necessary to understand the disintegration mechanisms of liquid jet. To understand the disintegration mechanisms of liquid jet, the disintegration phenomena and uniform droplet production regions of testing liquid jet was investigated by means of longitudinally vibration capillary nozzle, which was injected the testing liquids. The testing liquids were light oil and light oil and light oil blended with 25wt% fish oil (File fish oil, Sardine fish oil, Alaska pollac oil) The results can be summarized as follows: 1. The uniform droplet phenomena have been changed according to the frequency of capillary tube, the jet velocity and physical properties of testing oils. 2. Within the region of uniform droplet, Reynold number was increased as Weber number increases. 3. The lower limit of wave length in which uniform droplet was produced 0.8d which was lower than Rayleigh wave length 4. The light oil blended with file fish oil which has lower viscosity and surface tension had the widest uniform droplet production region on the frequency and velocity among testing oils. But light oil blended with sardine fish oil were similar with light oil in the uniform production region.

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고속 회전 유연 디스크 시스템에서 곡면 안정기에 가공된 모세관형 오리피스의 감쇠계수 해석 (An Analysis of Damping Coefficients for Capillary Type Orifices on a Curved Stabilizer used in a High Speed Rotating Flexible Optical Disk System)

  • 송기욱;임윤철
    • 정보저장시스템학회논문집
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    • 제7권1호
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    • pp.25-30
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    • 2011
  • In the last couple of years, the flexible optical disk(FOD) system that consists of a thin polycarbonate(PC) film of 95 ${\mu}m$ thick, a rigid stabilizer, and a high speed spindle motor has been spot-lighted as the next-generation optical system for archival use of digital data. The air film between the rotating disk and stabilizer provides a means for damping out the lateral disk vibrations. However, its damping-capability drops significantly as the rotational speed of the disk exceeds a specific limit and, eventually, the disk vibration propagates inward causing the whole span of the disk exhibits large vibration amplitudes. Based on the numerical simulations as well as the experimental results, the present work aims to evaluate the damping coefficient of the air-film near the outer region of the disk where the capillary type orifices are applied to the edge of the curved stabilizer.

모세관 맥동파 영상을 이용한 맥파 측정 시스템 (Pulse wave Measurement System by analyzing a Moving Pulse Image in the Capillary Tube)

  • 이우범;최창열;홍유식;이상석;남동현
    • 한국인터넷방송통신학회논문지
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    • 제12권2호
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    • pp.145-151
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    • 2012
  • 심혈관계 질환의 발병 위험요인 분석이 가능한 맥진기는 한방 의료기기에서 대표적인 연구 분야 가운데 하나이다. 그러나 기존의 대부분의 센서 기반의 맥진기는 측정시의 맥박 박동처와 센서부의 접촉상태에 따른 편위, 검출된 파형의 부정확성 및 파형분석의 어려움 등에 있어서 문제점이 발생한다. 따라서 본 논문에는 특성 센서를 사용하지 않고 단지 맥동에 의해서 유발되는 모세관 시험액의 상태 변화를 촬영한 맥동영상을 분석하여 환자의 맥파의 측정이 가능한 맥진기를 제안한다. 제안한 방법에서는 맥동영상 분석을 위한 시약영역 추출, 이진화, 수정된 열림연산, 변위측정 등의 영상처리 방법들이 적용된다. 제안한 맥진기의 성능 평가를 위해서는 추출된 압맥파로부터 맥파분석에 필수적인 5가지 주요 특징점에 대한 추출률을 측정한 결과 성공적인 결과를 보였다.

모세관 전기영동 장치를 이용한 음이온계 계면활성제의 분석 (Analysis of the Anionic Surfactants by Capillary Electrophoresis)

  • 정혁;김승선;이병민;강호철;이원;김해동
    • 분석과학
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    • 제7권4호
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    • pp.435-440
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    • 1994
  • 모세관 전기영동 장치를 이용하여 금속 표면 세척제(상품명 BFA와 BCA) 2종에 포함된 음이온 계면활성제에 대한 정성 및 정량분석을 수행하였다. Acetonitrile과 sodium benzoate를 포함하는 pH 10의 완충용액을 이용하여 18kV의 전압하에서 분리한 결과 $10^4$ 이상의 이론단수를 보이는 좋은 electropherogram을 얻을 수 있었다. S/N~3인 농도를 기준으로 검출한계는 ~5ppm이었으며 표준물질을 이용하여 얻은 검정곡선의 경우 농도가 10~100ppm의 범위에서 ~0.99 이상의 상관계수를 갖는 좋은 직선성을 보였으며, 이러한 결과를 바탕으로 분석한 결과 BFA의 경우 음이온 계면활성제의 각 성분은 octanoate, decanoate, dodecanoate, tetradecanoate, hexadecanoate등이었으며 상대비는 각각 1.0 : 1.0 : 6.5 : 2.1 : 0.8이었다.

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표면 요철이 발달된 캐필러리 적용에 따른 Cu 와이어의 본딩 특성 (Enhancement of Cu Wire Bondability by Increasing the Surface Roughness of Capillary)

  • 이종현;김주형;강홍전;김학범;문정탁;류도형
    • 대한금속재료학회지
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    • 제50권12호
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    • pp.913-920
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    • 2012
  • In spite of some problems in processability and bondability, Au wires in the microelectronics industry are gradually being replaced by copper wires to reduce the cost of raw material. In this article, the effects of surface roughness enhanced capillaries on thermosonic Cu wire bonding were evaluated. The roughness-enhanced zirconia toughened alumina (ZTA) capillaries were fabricated via a thermal grooving technique. As a result, the shear bond strength of first bonds (ball bonds) bonded using the roughness-enhanced capillary was enhanced by 15% as compared with that of normal bonds due to more effective plastic deformation and flow of a Cu ball. In the pull-out test of second bonds (stitch bonds), processed at two limit conditions on combinations of process parameters, the bond strength of bonds formed using the roughness-enhanced capillary also resulted in values higher by 55.5% than that of normal bonds because of the increase in the bonding area, indicating the expansion of a processing window for Cu wire bonding. These results suggest that the adoption of roughness-enhanced capillaries is a promising approach for enhancing processability and bondability in Cu wire bonding.

Development of a biosensor from aptamers for detection of the porcine reproductive and respiratory syndrome virus

  • Kuitio, Chakpetch;Rasri, Natchaya;Kiriwan, Duangnapa;Unajak, Sasimanas;Choowongkomon, Kiattawee
    • Journal of Veterinary Science
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    • 제21권5호
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    • pp.79.1-79.12
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    • 2020
  • Background: Recently, the pork industry of Thailand faced an epidemic of highly virulent strains of porcine reproductive and respiratory syndrome virus (PRRSV), which spread throughout Southeast Asia, including the Lao People's Democratic Republic and Cambodia. Hence, the rapid and on-site screening of infected pigs on a farm is essential. Objectives: To develop the new aptamer as a biosensor for detection PRRSV which are rapid and on-site screening of infected pig. Methods: New aptamers against PRSSV were identified using the combined techniques of capillary electrophoresis, colorimetric assay by gold nanoparticles, and quartz crystal microbalance (QCM). Results: Thirty-six candidate aptamers of the PRRSV were identified from the systematic evolution of ligands by exponential enrichment (SELEX) by capillary electrophoresis. Only 8 out of 36 aptamers could bind to the PRSSV, as shown in a colorimetric assay. Of the 8 aptamers tested, only the 1F aptamer could bind specifically to the PRSSV when presented with the classical swine fever virus and a pseudo rabies virus. The QCM was used to confirm the specificity and sensitivity of the 1F aptamer with a detection limit of 1.87 × 1010 particles. Conclusions: SELEX screening of the aptamer equipped with capillary electrophoresis potentially revealed promising candidates for detecting the PRRSV. The 1F aptamer exhibited the highest specificity and selectivity against the PRRSV. These findings suggest that 1F is a promising aptamer for further developing a novel PRRSV rapid detection kit.