• Title/Summary/Keyword: Capillary Pressure

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Patterning of liquid crystal alignment layers using selective dewetting process in a thermoplastic polymer film

  • Kim, Hak-Rin;Shin, Min-Soo;Lee, You-Jin;Kim, Jae-Hoon
    • 한국정보디스플레이학회:학술대회논문집
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    • 2006.08a
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    • pp.1719-1722
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    • 2006
  • We proposed a soft-lithographic method for aligning a liquid crystal (LC) in patterned azimuthal orientations. It is demonstrated that a thermoplastic polystyrene layer is patterned from a thermally stable polyimide layer via pressure-assisted capillary force lithography, which provides multidirectional LC alignment condition simply followed by a unidirectional rubbing process.

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Scientific Appreciation of Groundwater in the Hydrologic Cycle. - Some Experimental Results Concerning Rapid Water Table Response to Surface Phenomena.

  • Kayane, Isamu
    • Water for future
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    • v.22 no.3
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    • pp.289-298
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    • 1989
  • A review is made of transient phenomena ralation to flow in the vadose zone. Reviewed topics include rapid water table response to rainfall, pulsating flow due to pressure perturbations in the vasoes zone, and the wave-like propagation of increased soil moisture caused by intermittent rainfall. As a basis of interpreting these phenomena, zoning of the vadose zone into a residual water zone, an unsaturated capillaty zone, and a saturated capillary zone are proposed. Possible implications with respect to hydrological processes relating to these phenomena are discussed.

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Hemodynamic Evaluation of Acute Mitral Valve Insufficiency Model induced by Chordae Tendinae Rupture in Normal Dogs (개에서 건삭파열로 유발한 급성 이첨판 폐쇄부전 모델의 혈류역학적 평가)

  • Kim, Sehoon;Kim, Nam-Soo;Lee, Ki-Chang;Kim, Jong Min;Kim, Min-Su
    • Journal of Veterinary Clinics
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    • v.31 no.5
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    • pp.367-370
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    • 2014
  • The study was to observe hemodynamic alterations of cardiac function to design a model of canine mitral valve insufficiency (MVI) based on chordae tendinae rupture (CTR). Ten healthy beagles with normal heart function were used in this study. To measure hemodynamics, the patient monitor was equipped for invasive blood pressure and a Swan-Ganz catheter. Hemodynamic alterations were checked promptly during CTR procedures. MVI model was made by transection of the chordae tendinae with small arthroscopy hook knife through $5^{th}$ intercostal open chest. Color Doppler at the level of the mitral valve showed high-velocity regurgitant flow immediately after CTR at intraoperative echocardiography. In hemodynamic measurements, pulmonary capillary wedge pressure (PCWP) was significantly increased, while mean arterial pressure (MAP), venous pressure (VP), pulmonary arterial pressure (PAP), cardiac output (CO) and cardiac index (CI) were significantly decreased after CTR. It was known that the left atrium was overloaded by regurgitant volume from the left ventricle. In conclusion, the MVI model induced by CTR technique in this study should be used as suitable one for the effective research of canine mitral valve disease. Further study should be needed to measure the chronic alternation of mitral valve in the model.

A Study on the Relationship between Vascular Perfusion and Interface Pressure on the Ischial Tuberosity in the Sitting Posture (않은 자세에서 둔부 좌골결절의 접촉압력과 혈류량과의 관계에 대한 연구)

  • Heo, Hyun;Bae, Tae-Soo;Mun, Mu-Sung
    • Journal of the Korean Society for Precision Engineering
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    • v.24 no.7 s.196
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    • pp.126-132
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    • 2007
  • Pressure-induced decubitus is a serious disease among the elderly people. Interface pressure occluding vascular perfusion is known to be a cause of decubitus. Therefore, it is essential to quantify the relationship between vascular perfusion and interface pressure among the elderly people to understand more about decubitus. Nine healthy elderly people (57.8$\pm$ 5.6 years, 63.3$\pm$ 7.0kg, 1.68$\pm$ 0.05m) were participated. Three healthy young people (31.7$\pm$ 3.2 years, 74.7$\pm$ 8.4kg, 1.75$\pm$ 0.04m) were also examined to be compared with the elderly group. Capillary vascular perfusion on the ischial tuberosity was recorded in the sitting posture as pressures were applied from 15mmHg to 135mmHg. The average interface pressure to occlude vascular perfusion (the average occlusion pressure) under the ischial tuberosity was 115.7mmHg in the elderly group. This value was not significantly different from the average occlusion pressure of the young group. Obesity effect on the occlusion pressure was investigated among the elderly group. The result was not significantly different between the obesity and the normal group in this study. This is a preliminary study to unveil the complicated cause of pressure-induced decubitus associated with occlusion of vascular perfusion. More subjects are required for the future study.

Modeling of the Tensile Strength of Unsaturated Granular Soil Using Soil-water Characteristic Curve (흙-수분 특성 곡선을 이용한 불포화모래의 인장강도 모델링)

  • Kim Tae-Hyung;Kim Chan-Kee;Kim Tae-Hoon
    • Journal of the Korean Geotechnical Society
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    • v.20 no.7
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    • pp.171-181
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    • 2004
  • This study was conducted to explore the tensile strength models in granular soil at the full range of unsaturated state. Direct tension experiments were carried out with a newly developed direct tension technique. The measured experimental data were compared with theoretical models developed by Rumpf and Schubert for monosized ideal particulate solids at the unsaturated state. To do this, the soil-water characteristic curve obtained from a suction-saturation experiment was used to define the unsaturation state and the negative pore water pressure with different water content levels, which are important factors in theoretical tensile strength models. The nonlinear behavior of the tensile strength for unsaturated granular soil at the pendular state is appropriately simulated with Rumpf's model. For the funicular and capillary states, the predicted trend by Schubert's model is properly matched with the experimental data: tensile strength steadily increases and reaches a maximum value and then decreases until it reaches zero. This comparison supports the concept that the tensile strength of unsaturated real granular soil can be approximately simulated with theoretical models.

Discrimination of Geographical Origin for Astragalus Root (Astragalus membranaceus) by Capillary Electrophoresis and Near-Infrared Spectroscopy (Capillary electrophoresis 및 근적외선분광분석기를 이용한 황기의 원산지 판별)

  • Kim, Eun-Young;Kim, Jung-Hyun;Lee, Nam-Yun;Kim, Soo-Jeong;Rhyu, Mee-Ra
    • Korean Journal of Food Science and Technology
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    • v.35 no.5
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    • pp.818-824
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    • 2003
  • Capillary electrophoresis (CE) and near-infrared spectroscopy (NIRS) were performed to discriminate astragalus roots (Astragalus membranaceus) according to geographical origin (domestic or foreign). Two-hundred-and-four astragalus roots were extracted with 30% methanol in 0.1 M phosphate buffer (pH 2.5) and separated in a uncoated fused-silica $(50\;{\mu}m{\times}27\;cm)$ capillary. Conditions for optimal analysis included: temperature $-45^{\circ}C$, voltage -14 kV, and pressure injection time -8 sec. The optimal separation buffer was 0.1 M phosphate buffer (pH 2.5) containing 40 mM hexane sulfonic acid with 20% 2-methoxy ethanol. Raw NIR spectra were obtained using NIRS, and modified partial least square regression was used to develop the prediction model. The correlation coefficient and standard error of prediction were 0.915 and 14.3%, respectively. Under the optimal conditions established for CE and NIRS, the geographical origins of the astragalus roots were correctly identified in 80 and 97%, respectively. Astragalus roots that were not discriminated by NIRS were correctly discriminated by CE. Hence, CE and NIRS are potential methods for discriminating the geographical origins of astragalus roots that complement one another.

A Study on the Related Factors and the Change after Foot-reflexo-massage Education Program for Diabetic Patients (당뇨병 환자의 발반사요법 교육프로그램 후 발관리지식, 자가간호행위, 생리적지표의 변화 및 관련요인분석)

  • Lee, Young-Hee
    • Korean Journal of Adult Nursing
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    • v.16 no.2
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    • pp.222-232
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    • 2004
  • Purpose: The purpose of this study was to identify the change in foot care knowledge, self care behavior, and physiologic indexes after foot reflexomassage education program, and the related factors. Method: Data were collected from 20 patients who were visited out patients clinic. The change and difference were analyzed with non-parametric statistics. Result: There were significant differences in foot care knowledge(P=.001), self care behavior(P=.000), dosalis pedis blood flow volume (P=.011), skin temperature of foot(P=.001), dorsalis pedis pulse(P=.000), capillary filling time of foot (P=.000) between pre and post. The level of changes of foot care knowledge was significant differences according to admission experience (P=.049), and negative related to systolic blood pressure(P=.028). The level of changes of self care behavior was related to age(P=.049), that of dosalis pedis blood flow was significant difference according to smoking(P=.042), that of skin temperatureof foot(P=.002) and dosalis pedis pulse(P=.038) were significant difference according to weight. The level of changes of capillary filling time of foot was related to diagnosis period(P=.014). Conclusion: Foot-Reflexo-Massage education program is an effective nursing intervention to promote foot care in diabetic patients. And the related factors can be recommended for the management of diabetic patients.

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Synthesis and Characterization of Methyltriethoxysilyl-Mediated Mesoporous Silicalites

  • Rabbani, Mohammad Mahbub;Oh, Weon-Tae;Nam, Dae-Geun
    • Transactions on Electrical and Electronic Materials
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    • v.12 no.3
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    • pp.119-122
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    • 2011
  • A series of mesoporous silicalites was synthesized using different compositions of tetraethylorthosilicate and methyltriethoxysilane (MTES) as the silica source. Cetyltrimethylammonium bromide was used as the organic template. Their detailed pore structures were investigated by transmission electron microscopy, X-ray diffraction, and N2 adsorption method. The thermal properties of these silicalites were studied by thermogravimetric analysis. The increased amount of MTES destroyed mesoporous channels and reduced pore sizes from 3.4 nm to 2.8 nm in calcined silicalites. The calcined silicalite transformed completely into an amorphous state at 30% MTES loading. Methyl pending groups of MTES hindered the structural ordering of ≡Si-O- frameworks, resulting in an amorphous structure. This was caused by the insufficient formation of supramolecular assembly with the organic template. No capillary condensation step was found in MS 7/3 silicalite. The other capillary condensation steps shifted toward the lower relative pressure with increasing MTES content, indicating the reduction of pore sizes.

An Experimental Investigation into the Characteristics of Sampling Module for East-Response Co2 Concentration Analyzer with NDIR (비분산 적외선 분광법을 이용한 Co2농도 고속 분석기의 Sampling Module 특성에 관한 실험적 연구)

  • Kim, Woo-Seok;Shon, Deok-Young;Park, Young-Moo;Yoo, Jae-Suk;Lee, Jong-Hwa
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.27 no.3
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    • pp.398-405
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    • 2003
  • A fast response analyzer for measuring carbon dioxide concentration has been developed for transient characteristic and researches tested on internal combustion engine. The analyzer uses the well known NDIR(Non-Dispersive Infrared) method with miniaturized detection system, giving a time constant of approximately 30 microsecond, and sampling module consists of capillary tube. Since the transit time and the time constant of the sampling system depend on the sampling conditions, it is necessary to investigate the characteristics of sampling system before applied to exhaust gas measurement in engine. A unique method was designed to study the influence of the diameter of transfer sample line and operating conditions of the FRNDIR on transit time and time constant. A database of transit time and time constant was built up for different measured and simulated pressure conditions. The database can be used for correcting eventual $CO_2$ concentration measurement.