• 제목/요약/키워드: water swelling

검색결과 816건 처리시간 0.027초

Non-swelling type의 Hydrophilic polyurethane 합성 및 응용에 관한 연구 (Synthesis and Application for Hydrophilic Polyurethane of Non-swelling Type)

  • 양정한;전재우;염정현;김덕한;오경석;윤남식
    • 한국염색가공학회지
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    • 제23권2호
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    • pp.118-130
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    • 2011
  • In this study, hydrophilic polyurethane (PU) was synthesized by one shot process to get good non-swelling effect and to keep high breathability using reactive silicone oil of mono terminal and bi-terminal types. We also blended non reactive silicone oil with pure hydrophilic PU to compare non-swelling effect and breathability with hydrophilic PU synthesized by the two types of reactive silicone oils. The hydrophilic films were analyzed by nuclear magnetic resonance (NMR) spectroscopy, scanning electron microscope (SEM), Fourier transform infrared (FT-IR) spectroscopy, X-ray photo electron (XPS) spectroscopy, energy dispersive spectrometry (EDS), breathability, waterproofness, tensile strength, contact angle and swelling effect. The results showed that the film made by hydrophilic PU which was synthesized with mono terminal type silicone oil provided good non-swelling effect and acceptable moisture permeability due to the modified surface properties.

A model for calculating the irradiation swelling of AgInCd absorber in nuclear control rods

  • Hongsheng Chen;Hongxing Xiao;Chongsheng Long;Xuesong Leng
    • Nuclear Engineering and Technology
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    • 제56권2호
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    • pp.552-557
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    • 2024
  • The actual swelling of AgInCd absorber might exceed the predicted swelling value after years of service in pressurized water reactors, and the chemical and microstructural changes of AgInCd absorber induced by transmutation reactions are the main reason for the swelling acceleration of AgInCd absorber. In the present study, a model for calculating the irradiation swelling of AgInCd absorber in nuclear control rods is developed according to chemical and microstructural changes of AgInCd absorber. In this model, the chemical compositions of AgInCd absorber as a function of the thermal neutron fluence are firstly calculated, and then the volume of AgInCd absorber after irradiation is obtained on the basis of the crystallographic parameters of phases in the AgInCd absorber, and the irradiation swelling of AgInCd absorber is finally calculated. The crystallographic parameters can be obtained by preparing the simulated AgInCd alloys and fitting the experimental data. The model calculating results of irradiation swelling are in good agreement with the actual swelling data in literature. More importantly, the present model can well explain the EPRI results of the acceleration in the diametral swelling rate above 6-8 × 1020 n/cm2 and the decrease in the diametral swelling rate above about 2 × 1021 n/cm2.

Leachability of Zinc Borate-Modified Oriented Strandboard (OSB)

  • Lee, Sun-Young;Wu, Qinglin
    • Journal of the Korean Wood Science and Technology
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    • 제35권5호
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    • pp.46-57
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    • 2007
  • The leachability of boron in zinc borate (ZB)-modified oriented strandboard (OSB) from southern wood species was investigated in this study. The leaching experiments were conducted by exposing edge-sealed OSB samples under running water at $31^{\circ}C$ for 8, 24, 72, and 216 h. The results from leached samples were compared with those from the unleached controls. Boron leaching of the modified OSB occurred upon the initial water exposure, and the leaching rate decreased as the leaching time increased. Initial boric acid equivalent (BAE) level, wood species, and sample thickness swelling significantly influenced the leachability. There was no consistent effect of polyethylene glycol (PEG) on zinc borate leaching. The glue-line washing within OSB due to thickness swelling of the test samples under water and decomposition of the borate to form water-soluble boric acid were thought to be two possible causes for the observed leaching. The relationship between assayed BAE and leaching time followed a decaying exponential function for zinc borate treated OSB. From the boron/zinc ratio after each leaching period, boron element in ZB was more or less leachable. The material constant of the regression models allowed comparing the leachability of the modified OSB for various wood species. An unified leaching method for treated wood composite materials is needed.

Inhibition of Browning and Preference Improvements of Dioscorea batatas through the Addition of Sugar Alcohols and Organic Acids

  • Lee, Myung-Ki;Yang, Hye-Jung;Kim, Byoung-Mok;Jo, Ae-Ri;Park, Young-Min
    • Preventive Nutrition and Food Science
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    • 제14권3호
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    • pp.220-225
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    • 2009
  • In this study, the color value, water solubility, swelling power and sensory evaluation of Dioscorea batatas was examined with the addition of functional additives such as sugar alcohols and organic acids to investigate the browning inhibition and preference of these additives. Treatment with erythritol and citric acid were found to result in the highest hunter L-value, solubility and swelling power relative to the other functional additives. Therefore, erythritol and citric acid were selected as additives for Dioscorea batatas. The Dioscorea batatas containing the mixed additives (erythritol and citric acid) showed higher brightness, water solubility and swelling power than those containing only a single additive. In addition, the color and taste preference determined in the sensory evaluation had higher values when the mixed additives were used.

Numerical Simulations of the Moisture Movement in Unsaturated Bentonite Under a Thermal Gradient

  • Park, J.W.;K. Chang;Kim, C.L.
    • Nuclear Engineering and Technology
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    • 제33권1호
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    • pp.62-72
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    • 2001
  • The one-dimensional finite element program was developed to analyze the coupled behavior of heat, moisture, and air transfer in unsaturated porous media. By using this program, the simulation results were compared with those from the laboratory infiltration tests under isothermal condition and temperature gradient condition, respectively. The discrepancy of water uptake was found in the upper region of a bentonite sample under isothermal condition between numerical simulation and laboratory experiment. This indicated that air pressure was built up in the bentonite sample which could retard the infiltration velocity of liquid. In order to consider the swelling phenomena of compacted bentonite which cause the discrepancy of the distribution of water content and temperature, swelling and shrinkage factors were incorporated into the finite element formulation. It was found that these factors could be effective to represent the moisture diffusivity and unsaturated hydraulic conductivity due to volume change of bentonite sample.

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Genotypic and Environmental Effects on Flour Properties in Korean Winter Wheat

  • Hong, Byung-Hee;Park, Chul-Soo;Baik, Byung-Kee
    • 한국작물학회지
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    • 제47권1호
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    • pp.1-12
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    • 2002
  • Flour characteristics of Korean winter wheat grown in Suwon in 1997 and 1998, and in Suwon and Deokso in 1998 were evaluated. Korean winter wheat cultivars were significantly influenced by years and locations in flour properties such as ash content, protein content, damaged starch content, starch swelling volume and power. Protein content was highly correlated with starch damage and alkaline water retention capacity. There were highly significant correlations between mixing time of mixograph and SDS sedimentation volume. Swelling properties of flour and starch were highly correlated with pasting properties of flour and starch, respectively. Compared to commercial flours for baking, Alchanmil, Gobunmil, Keumkangmil and Tapdongmil showed similar protein content, SOS sedimentation volume and mixograph mixing time. Eunpamil, Geurumil, Olgeurumil, Suwon 258, Suwon 261, Suwon 265, Suwon 275, Suwon 276, Suwon 277, Suwon 278 and Urimil had similar values to commercial noodle flours in SDS sedimentation volume. Alchanmil, Olgeurumil, Suwon 274, Suwon 275, Suwon 276 and Urimil showed higher swelling and pasting properties than the others. Chokwang, Olgeurumil, Suwon 277 and Urimil were similar to commercial cookie flours. Friabilin-absence lines showed higher protein content and starch damage than those of friabilin-presence lines. Absence lines of 1D$\times$2.2 + 1Dy12 subunit in high molecular weight glutenin subunits showed higher SDS sedimentation volume and mixing time of mixograph than those of presence lines.

Swelling Behavior and Drug Release of Poly(vinyl alcohol) Hydrogel Cross-Linked with Poly(acrylic acid)

  • Byun, Hong-Sik;Hong, Byung-Pyo;Nam, Sang-Yong;Jung, Sun-Young;Rhim, Ji-Won;Lee, Sang-Bong;Moon, Go-Young
    • Macromolecular Research
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    • 제16권3호
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    • pp.189-193
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    • 2008
  • Thermal cross-linking method of poly(vinyl alcohol) (PVA) using poly(acrylic acid) (PAA) was carried out on PVA/PAA hydrogels. The level of gelation was measured in the PVA/PAA hydrogels with various PAA contents. The swelling behavior at various pHs showed that the swelling kinetics and water contents of the PVA/PAA hydrogels reached equilibrium after 30 h, and the time to reach the equilibrium state decreased with increasing PAA content in the hydrogel. The water content increased with increasing pH of the buffer solution. The permeation and release of the drug were tested using indomethacin as a model drug. The permeated and released amounts of the drug increased with decreasing the PAA content because of the low free volume in the hydrogel due to the higher cross-linking density. The kinetic profile of drug release at various pHs showed that all samples reached the equilibrium state within the 5 h.

동해안 너울성 파도 예측을 위한 머신러닝 모델 연구 (A Study of Machine Learning Model for Prediction of Swelling Waves Occurrence on East Sea)

  • 강동훈;오세종
    • 한국정보기술학회논문지
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    • 제17권9호
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    • pp.11-17
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    • 2019
  • 최근 들어 동해안에서 너울성 파도에 의한 손실이 빈번히 발생하고 있다. 너울성 파도는 다양한 요인들이 결합되어 발생하기 때문에 예측이 어렵다. 본 연구에서는 머신러닝 기술에 기초하여 동해안에서 너울성 파도의 발생을 예측하는 모델을 제안하였다. 모델 개발을 위해 포항 신항의 하역중단 데이터 및 신항 부근의 기압, 풍속, 풍향, 수온 등의 기상자료를 수집하였다. 수집한 데이터로부터 너울발생에 중요한 영향을 미치는 변수들을 선별하였으며, 모델 개발을 위해 다양한 머신러닝 예측 알고리즘들을 테스트 하였다. 그 결과 조위, 수온, 기압이 너울 발생 예측을 위한 주요 변수로 확인이 되었고, Random Forest 모델이 가장 우수한 성능을 보였으며. 모델의 예측 정확도는 88.6%이다.

Inhibitory Effects of Ginsenosides on Glutamate-Induced Swelling of Cultured Astrocytes

  • Seong, Yeon-Hee;Koh, Sang-Bum;Kim, Hack-Seang
    • Journal of Ginseng Research
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    • 제24권3호
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    • pp.138-142
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    • 2000
  • 흰쥐 대뇌겉질로부터 별아교세포를 배양하여 흥분성아미노산인 L-glutamate에 의하여 유발되는 세포종창(astrocytic swelling)에 대한 ginsenosides의 억제효과를 검토하였다. Glutamate(0.5 mM)를 세포에 가하고 1시간동안 배양하면 swelling을 일으켜, 세포내의 물의 용적([$^3$H]OMG의 uptake량으로 측정)은 대조세포에 비하여 약 2배의 증가를 나타냈다. Glutamate와 함께 ginsenosides Rb$_2$와 Rc를 가하고 배양하면 glutamate에 의한 astrocytic swelling이 용량의존적으로 감소하였다. 세포는 Rb$_2$와 Rc(0.5 mg/ml)에 24시간까지 노출시켜도 MTT reduction이 감소하지 않는 것으로 보아 이 ginsenosides에 의한 swelling의 억제효과는 세포막의 손상에 의한 것이 아님을 알 수 있었다. Rb$_2$와 Rc는 glutamate에 의한 세포내 $Ca^{2+}$농도의 상승을 억제하였다. 따라서 Rb$_2$와 Rc는Ca$^{2+}$의 유입을 억제하므로서 glutamate에 의한 astrocytic swelling을 억제하는 것으로 생각된다.

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금궤요략${\cdot}$수기병맥증병치제십사(水氣病脈證幷治第十四)에 대한 연구 (Study On the 'Diagnosis and Trearment of Edema' in the Chapter 14 of Synopsis of Golden Chamber)

  • 노승조;박금숙;권미자;이영섭;정헌영
    • 동의생리병리학회지
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    • 제22권1호
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    • pp.60-81
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    • 2008
  • This thesis is written about the causes, the processes and the treatments of edema. It consists of 31 chapters. Covering 11 chapters, there are prescriptions and constructions. When one of the organs fails to work metabolizing water, you can have edema. It is the result of the accumulation of excess fluid under the skin. Edema most commonly occurs in the head facial, the palpebral portion, the feet and legs or all the body. Sometimes it is accompanied with ascites. There are three classifications in the thesis. First, according to the cause and the symptom of disease, it is divided into 5 types. Type 1. The swelling caused by the disorder of the lungs from the troubling wind. Type 2. The swelling caused by the weak spleen. Type 3. The swelling caused by abnormal condition between the kidneys and the lungs. Type 4. The swelling in abdomen caused by the weak kidneys. Type 5. The swelling (Yellow sweat) caused by the heat inside body as water outside. Second, the swelling and the abnormal symptom of five viscera. Third, the swelling accompanied with menstruation in female and with chilliness. In short, the original textbook is showed that the treatment of edema focuses on the cause and the region of fluid accumulation. When the swelling is in the upper body or the cause of diseaseis outside, the useless humidity can be expelled through sweating. On the other hand, when the swelling is in the lower body or the cause of disease is inside, it is pushed out by urination. In this book, the author presents further treatments. And these treatments are often cited by doctors after ages. Even one of them suggested that the swelling be divided by cosmic dual forces. In spite of many researches, it is too complicate for us to understand the writer’s intend. For that reason, comparing with other medical books and referring to guides explained by doctors, I have studied the textbook to help understand.