• Title/Summary/Keyword: plasma in liquid

검색결과 613건 처리시간 0.037초

플라즈마 중합박막을 이용한 유기용매의 투과증발 (Pervaporation of Organic Solvents using Plasma Polymerized Thin Film)

  • 김성오;박복기;김두석;박진교;류성렬;이진;나동근;이덕출
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 D
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    • pp.1702-1703
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    • 1999
  • We have prepared the plasma-polymerized membrane for pervaporation of organic-liquid mixtures by the plasma polymerization technique. Plasma polymerization techniques were utilized in the development of hydrophilic composite membranes having high hydrogen ion permeability and excellent dimensional stability. To develop an organic liquid permselective membrane. suppressing membrane swelling as well as enhancing the solubility difference is important, the objectives of the present study are to design a suitable membrane for an organic-mixture system by the control of the plasma-polymer solubility.

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액체로켓엔진 연소기에 적용된 니켈-크롬 코팅의 열차폐 효율과 내구성 (Thermal Barrier Efficiency and Endurance of Ni-Cr Coating in Liquid Rocket Engine Combustor)

  • 이광진;임병직;김종규;한영민;최환석
    • 항공우주기술
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    • 제8권1호
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    • pp.138-143
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    • 2009
  • 액체로켓엔진 연소기에 적용된 대기 플라즈마 코팅 및 전해/무전해 도금 코팅의 열차폐 효율과 내구성 평가를 수행하였다. 연소시험 결과 대기 플라즈마 방식의 $ZrO_2$, NiCrAlY 코팅은 로켓엔진 연소기의 초음속 유동영역에서 코팅이 표면에서 박리되는 현상이 간헐적으로 발생하였으며 따라서 이러한 문제를 극복할 수 있는 대체 코팅 방식이 요구되었다. 시험 결과 열차폐 효율 및 내구성 관점에서 대기 플라즈마 방식의 $ZrO_2$, NiCrAlY 코팅의 대안으로 무전해/전해 방식을 사용한 니켈-크롬 코팅을 사용할 수 있음을 알 수 있었다.

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Determination of nadolol enantiomers in human plasma using a coupled achiral-chiral high-performance liquid chromatography method

  • Lee, Seung-Beom;Pham, Thuy-Vy;Mai, Xuan-Lan;Le, Thi-Anh-Tuyet;Nguyen, Thi-Ngoc-Van;Kang, Jong-Seong;Mar, Woongchon;Kim, Kyeong Ho
    • 분석과학
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    • 제33권2호
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    • pp.59-67
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    • 2020
  • Nadolol is a β-blocker drug, which effectively manages hypertension and angina pectoris. Its chemical structure allows the formation of four possible stereoisomers. A coupled column high-performance liquid chromatographic (HPLC) system with UV and fluorescence detection was investigated for simultaneously determining four nadolol enantiomers in human plasma. The plasma samples were prepared using a convenient liquid-liquid extraction process and passed through HPLC. Nadolol was initially separated from the endogenous compounds or other impurities in human plasma on a Phenomenex silica column, and its enantiomers were resolved and determined on a Chirapak AD-H column. The developed HPLC method achieved an effective chiral separation and significantly eliminated endogenous compound interference. This optimal HPLC method was validated following FDA guidelines. The results showed good selectivity, linearity, accuracy (90.50 % - 105.27 %), and precision (RSDs < 9.52 %) for each enantiomer. This method was also successfully applied to determine nadolol enantiomers in the plasma samples of a healthy male volunteer (after orally administering 80 mg racemic nadolol), proving its suitability for nadolol stereoselective pharmacokinetic studies.

Determination of Aloesin in Plasma by High-Performance Liquid Chromatography as Fluorescent 9-Anthroyl Derivative

  • Kim, Kyeong-Ho;Lee, Jin-Gyun;Park, Jeong-Hill;Shin, Young-Geun;Lee, Seung-Ki;Cho, Tae-Hyung
    • Archives of Pharmacal Research
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    • 제21권6호
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    • pp.651-656
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    • 1998
  • A sensitive high-performance liquid chromatographic (HPLC) method for the determination of aloesin in plasma was developed. After solid-phase extraction from plasma and derivatization of aloesin and compound AD-1, which was prepared from aloesin as a internal standard, with 9-anthroylnitrile in the presence of quinuclidine, the derivatives were separated on a Inertsil ODS-3 column using acetonitrile/methanol/water (3:1:6) as a mobile phase, and detected fluorimetrically at 460nm with excitation at 360nm. The detection limit of aloesin was 3.2ng/ml in plasma (S/N=3).

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혈장중 Ofloxacin의 HPLG분석 (High Performance Liquid Chromatographic Assay of Ofloxacin in Plasma)

  • 백채선;김영수
    • 한국임상약학회지
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    • 제10권1호
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    • pp.38-41
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    • 2000
  • A high-performance liquid chromatographic method with fluorometric detection was evaluated for analysis of ofloxacin in plasma. Biological fluids (plasma, $200\;{\mu}L$) were prepared for assay by protein precipitation with chlorofurm. The detection of ofloxacin and triamterene as an internal standard were performed at 358 nm for excitation and 495 nm for emission. The HPLC separation was carried out on Ultrasphere ODS column (4.6 mm${\times}25\;cm,\;5\;{\mu} m$) with acetonitrile $(45\%)$-phosphoric acid $(1.5\%)\;containing\;0.3\%$ sodium laurylsulfate as the mobile phase. The flow-rate was 1.0 mL/min. The calibration graphs were linear from 3.0 to 80 ng/mL with r=0.998. The minimal detectable concentration in plasma was 1.5 ng/mL. The proposed technique is reproducible, selective, reliable and sensitive.

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3구 노즐을 이용한 플라즈마 가스 용존율 향상을 위한 플라즈마 공정의 최적화 (Optimization of Plasma Process to Improve Plasma Gas Dissolution Rate using Three-neck Nozzle)

  • 김동석;박영식
    • 한국환경과학회지
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    • 제30권5호
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    • pp.399-406
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    • 2021
  • The dissolution of ionized gas in dielectric barrier plasma, similar to the principle of ozone generation, is a major performance-affecting factor. In this study, the plasma gas dissolving performance of a gas mixing-circulation plasma process was evaluated using an experimental design methodology. The plasma reaction is a function of four parameters [electric current (X1), gas flow rate (X2), liquid flow rate (X3) and reaction time (X4)] modeled by the Box-Behnken design. RNO (N, N-Dimethyl-4-nitrosoaniline), an indictor of OH radical formation, was evaluated using a quadratic response surface model. The model prediction equation derived for RNO degradation was shown as a second-order polynomial. By pooling the terms with poor explanatory power as error terms and performing ANOVA, results showed high significance, with an adjusted R2 value of 0.9386; this indicate that the model adequately satisfies the polynomial fit. For the RNO degradation, the measured value and the predicted values by the model equation agreed relatively well. The optimum current, gas flow rate, liquid flow rate and reaction time were obtained for the highest desirability for RNO degradation at 0.21 A, 2.65 L/min, 0.75 L/min and 6.5 min, respectively.

Simplified HPLC Method for the Determination of Prazosin in Human Plasma and Its Application to Single-dose Pharmacokinetics

  • Gwak, Hye-Sun;Chun, In-Koo
    • Biomolecules & Therapeutics
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    • 제13권2호
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    • pp.90-94
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    • 2005
  • Prazosin hydrochloride is an antihypertensive drug with selective ${\alpha}_1$-adrenoreceptor blocking effects. A simple high performance liquid chromatographic method has been developed and validated for the quantitative determination of prazosin in human plasma. A reversed-phase C18 column was used for the separation of prazosin and terazosin (internal standard) with a mobile phase composed of water, acetonitrile and triethylamine(75:25:0.1, V/V;pH5.0) at a flow rate of 1.5 ml/min. the fluorescence detector was set at excitation and emissionwavelengths of 250 and 370 nm, respectively. Intra-and inter-day precision and accuracy were acceptable for all quality control samples including the lower limit of quantification of 0.5 ng/ml. Good recovery (>80%) was seen in plasma. Prazosin was stable in human plasma under various storage conditions. This method was used successfully for a pharmacokinetic study in plasma after oral administration of a single 2-mg dose as prazosin base to 16 healthy volunteers. The maximum plasma concentration of prazosin was 23.1 ${\pm}$ 16.5 ng/ml at 2.1 h, and the mean area under the curve and elimination half-life were calculated to be 108.4 ${\pm}$ 74.2 ng ${\cdot}$hr/ml and 2.5 ${\pm}$ 0.6 h, respectively.

Quantification of Fargesin in Mouse Plasma Using Liquid Chromatography-High Resolution Mass Spectrometry: Application to Pharmacokinetics of Fargesin in Mice

  • Lee, Min Seo;Lim, Chang Ho;Bang, Young Yoon;Lee, Hye Suk
    • Mass Spectrometry Letters
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    • 제13권1호
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    • pp.20-25
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    • 2022
  • Fargesin, a tetrahydrofurofuranoid lignan isolated from Flos Magnoliae, shows anti-inflammatory, anti-oxidative, anti-allergic, and anti-hypertensive activities. To evaluate the pharmacokinetics of fargesin in mice, a sensitive, simple, and selective liquid chromatography-high resolution mass spectrometric method using electrospray ionization and parallel reaction monitoring mode was developed and validated for the quantification of fargesin in mouse plasma. Protein precipitation of 6 µL mouse plasma with methanol was used as sample clean-up procedure. The standard curve was linear over the range of 0.2-500 ng/mL in mouse plasma with the lower limit of quantification level at 0.2 ng/mL. The intra- and inter-day coefficient variations and accuracies for fargesin at four quality control concentrations including were 3.6-11.3% and 90.0-106.6%, respectively. Intravenously injected fargesin disappeared rapidly from the plasma with high clearance values (53.2-55.5 mL/min/kg) at 1, 2, and 4 mg/kg doses. Absolute bioavailability of fargesin was 4.1-9.6% after oral administration of fargesin at doses of 1, 2, and 4 mg/kg to mice.

Determination of carvedilol in human plasma by high-performance liquid chromatography

  • Lee, Jung-Ae;Lee, Ye-Rie;Kim, Ho-Hyun;Lee, Hee-Joo;Lee, Kyung-Ryul
    • 대한약학회:학술대회논문집
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    • 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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    • pp.220.1-220.1
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    • 2003
  • A sensitive and selective liquid chromatographic method for the determination of carvedilol in human plasma was developed and validated. Analytes were separated on a XTerra C18 column with acetonitrile-methanol-30 mM KH$_2$PO$_4$ (pH 2.5) (20 : 20 : 60, v/v/v), as mobile phase. One mL plasma were pipetted into glass tubes and spiked with 0.05 mL of internal standard solution. After adding 7 mL of diethyl ether, the plasma sample was then shacked for 15 min. A centrifuged upper layer was back-extracted with 150 uL of 0.05 M sulfuric acid. (omitted)

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전자담배용 니코틴 원액 음독 후 발생한 심정지 1례 (A Case Report of Cardiac Arrest Following Intentional Ingestion of Liquid Nicotine for Electronic Cigarette)

  • 김정호
    • 대한임상독성학회지
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    • 제16권2호
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    • pp.172-175
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    • 2018
  • Acute nicotine poisoning by liquid nicotine for electronic cigarettes is becoming an increasing problem worldwide. On the other hand, there are no regulations regarding its concentration, container or labelling in Korea. This is the first case of a cardiac arrest after liquid nicotine ingestion that was confirmed by plasma nicotine detection in Korea. A 34-year-old male was found with a cardiac arrest at home by the emergency medical services crew, and had a return of spontaneous circulation after 27 minutes of cardio-pulmonary resuscitation. The cause of his cardiac arrest was suspected to be acute nicotine poisoning by the ingestion of liquid nicotine. Toxicology analysis of the National Forensic Service confirmed plasma nicotine, and the pharmacokinetic estimated average concentration of plasma nicotine at the time of the cardiac arrest was 29.7 mg/L, a lethal dose. He was hospitalized for further treatment, but was discharged after 20 days without any improvement. Considering the strong toxicity of nicotine, appropriate policy decisions are required for sales and distribution.