• Title/Summary/Keyword: 열희석법

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열유동 상분리막의 구조연구

  • ;;Douglass, K. Lolyd
    • Membrane Journal
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    • v.1 no.1
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    • pp.13-23
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    • 1991
  • 열유도 상분리법을 이용하여 제조되는 분리막의 구조 변화를 열역학 및 속도론적 관점에서 고찰하였다. Polypropylene과 희석제로서 n-alkanes, n-fatty acids, n,n-bis(2-hydroxyethyl) tallowamine을 model system으로 하였다. 고분자/희석제 system의 상변화의 종류에 따라 다양한 형태의 분리막구조가 얻어졌다. 분리막의 구조에 영향을 미치는 변수로서 고분자/희석제간의 interaction parameter, 희석제의 분자 크기, 용액의 조성, 냉각 조건, 희석제의 결정화 온도 등이며, 각 변수의 역할을 전자현미경을 사용하여 규명하였다. 열유동 상분리법에 의하여 제조된 분리막은 inter-spherulitic 및 intra-spherulitic pore의 이중 구조로 이루어짐을 확인하였다.

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Thermal Ion Mass Spectrometry with Isotope Dilution Method: An application to Rare Earth Element Geochemistry (동위원소희석법을 이용한 열이온 질량분석: 희토류원소 지구화학에의 응용)

  • ;;;增田彰正
    • The Journal of the Petrological Society of Korea
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    • v.10 no.3
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    • pp.190-201
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    • 2001
  • Isotope Dilution Mass Spectrometry(IDMS) is one of the analytical method which uses enriched isotope spikes and analyzes the abundance of element by comparison of the spectrum between spiked mass and non-spike mass. Especially, the Thermal Ion Mass Spectrometry with isotope dilution technique (in general ID-TIMS) is the most accurate method of the chemical analysis, which enables us to obtain the data better than 1% in accuracy and precision. In IDMS, enriched isotope spike is one of the most important factor in order to obtain the best data. For rare earth elements, in general, a mixture of /sup 138/La, /sup 142/Ce, /sup 145/Nd, /sup 149/Sm, /sup 151/Sm, /sup 151/Eu, /sup 157/Gd, /sup 163/Dy, /sup 167/Er, /sup 171/Yb, and /sup 176/Lu is used as composite spike. IDMS is very useful in geochronology and REE geochemistry. Especially, it is very effective in studying the “tetrad effect” of rare earth elements in natural samples.

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Comparative Evaluation of Cardiac Output using Echocardiography in Beagle Dogs (비글견에서 심초음파를 이용한 심박출량 측정에 관한 비교 연구)

  • Park, Kitae;Yeon, Seongchan;Lee, Heechun
    • Journal of Veterinary Clinics
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    • v.29 no.5
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    • pp.384-390
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    • 2012
  • Echocardiographic measurements of cardiac output, including the modified Simpson's method, Automated Contour Tracking(ACT) method, and left ventricular outflow method are well described methods of evaluating cardiac function due to its reliability and the benefits of its non-invasive technique in human medicine. The purpose of this study was to evaluate the accuracy of an echocardiography estimate of cardiac output in isoflurane-anesthetized beagle dogs and was to compare the ACT method to the other methods used in measurement of cardiac output. In healthy beagle dogs, cardiac output results by echocardiography estimate methods showed an excellent correlations with those by the thermodilution method (The modified Simpson's method : r = 0.815, $r^2=0.665$, y = 0.434x + 0.311 ; ACT method : r = 0.86, $r^2=0.748$, y = 0.391x + 0.242 ; ventricular outflow method : r = 0.691, $r^2=0.478$, y = 0.593x + 0.242). Among the results obtained, the ACT method showed the highest correlation coefficient. In conclusion, our study demonstrated that echocardiography estimate methods did not prove to be suitable in accurately measuring absolute cardiac output values but showed an excellent correlation with thermodilution method. Therefore, by using the measurement of cardiac output as supplemental data, echocardiography estimate methods can be used for detection and correction of hemodynamic disturbances during emergency and anesthesia in veterinary practice.

열유도상분리법에 의한 HDPE 중공사 분리막의 제조시 방사조건이 분리막 성능에 미치는 영향

  • Park, Seon-Hu;Kim, Dong-Hwa;Sun, Hyang;Ma, Seok-Il
    • Proceedings of the Membrane Society of Korea Conference
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    • 1997.10a
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    • pp.90-93
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    • 1997
  • 1. 서론 : 본 연구에서는 수처리용으로 사용되는 PE 중공사 분리막을 HDPE/LP 혼합계의 열유도 상분리법을 이용하여 제조하고 PE의 MPR(Melt Flow Rate), 희석제 함량, 방사조건 등이 중공사 분리막의 물성변화에 미치는 영향을 투수 계수를 중심으로 검토하였다.

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Effects of operations on the performance and structure of hollow fiber membrane (용융방사 조건에 따른 중공사막의 성능 및 구조변화)

  • 유종범;김성수
    • Proceedings of the Membrane Society of Korea Conference
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    • 1998.04a
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    • pp.65-67
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    • 1998
  • 1. 서론 : 내용매성, 내약품성 및 내열성 등이 탁월한 결정성 고분자를 소재로 하여 우수한 성능의 분리막을 제조하기 위하여 열유도 상분리법이 제안되었다. 열유도 상분리법은 먼저 고분자를 희석제와 함께 melt-blending하여 단일상의 균일한 용액을 만들고 이를 냉각시킴으로써 상분리가 일어나도록 유도하는 공정이다. (생략)

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Development of Impedance Cardiograph and its Application (임피던스 심장기록기의 개발과 응용)

  • Kim, Deok-Won;Kim, Jeong-Yeol;Kim, Won-Ky;Park, Sang-Hui
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.27 no.3
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    • pp.54-62
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    • 1990
  • The thermodiluton is a standard method to measure cardiac output in clinical medicine. However it has many disadvantages such as expensive instrument and measurement, limited number of measurement, pain, safety problem, and side-effect due to insertion of catheter into heart. Electrical Impedance Cardiography has no such disadvantages and that it can continuously monitor stroke volume, contractility of cardiac muscle, and systolic time interval (STI) as well as cardiac output. While this impedance technique has been widely used and vigorously studied adroad, it is not introduced yet in Korea. Thus an Impedance Cardiograph has been developed in order to introduce this new technique. Its accuracy also has been verified by simultaneous measurement of cardiac output with the thermodilution technique. Finally changes of cardiac function during exercise were also measured.

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Cardiac Output Measurement Platform Development Using Swan-Ganz Catheter in Cardiopulmonary Patients with More Accurate (Swan-Ganz Catheter를 이용한 심폐기능 이상자의 정확한 Cardiac Output 측정 플랫폼 개발)

  • Jeong, Yong-Hyun;Na, Sang-Sin;Kim, Young-Kil
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.15 no.7
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    • pp.1591-1597
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    • 2011
  • In this paper, on cardiopulmonary function in the intensive care unit over the direction of the state to define the diagnostic or therapeutic cardiac output Study on Implementation of measures as a platform, Swan-Ganz Catheter with sensor inserted into the body by inserting a saline solution Using temperature change caused by using thermodilution be used to obtain cardiac output. Swan-Ganz Catheter with temperature sensors and pressure sensors and sensor value which is entered through the acquisition more closely if the cardiac output CO, systemic and pulmonary vascular resistance, oxygen consumption and may be able to more accurately calculate the patient's condition than accurate diagnosis and treatment is possible.

The Comparison of Cardiac Outputs between Impedance Cardiography and Thermobilution Technique (임피던스 카디오그래피와 열희석법에 의한 심박출량의 비교)

  • 김덕원;이웅구
    • Journal of Biomedical Engineering Research
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    • v.9 no.2
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    • pp.165-170
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    • 1988
  • The purpose of this study was to prove the accuracy of impedance cardiography by measuring cardiac outputs of patients simultaneously by thermodilution method, and impedance cardiography developed in our department. The subjects were eight patients with mitral stenosis admitted to the cathete rization laboratory in Severance Hospital. The correlation coefficient was 0.895, which is thought quite high considering the fact that accuracy of cardiac outputs of patients with valvular diseases measured by both methods was known to be low.

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