• Title/Summary/Keyword: 흡수관

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표준형 원전을 위한 장주기용 개량연료 노심 해석

  • 이국종;최기용;이해찬;정선교
    • Proceedings of the Korean Nuclear Society Conference
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    • 1996.05a
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    • pp.73-79
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    • 1996
  • 현재의 원전 운용은 연료주기 비용을 최소화하여 경제성을 향상시키는 것이 세계적인 추세이다. 따라서 영광 3, 4호기 이후의 국내 원전 건설의 대부분이 될 한국 표준형 원전을 대상으로 하여, 현재 개발 중이거나 이미 실용화된 개량 원전 연료의 특성을 적용하여 실제 노심해석을 수행하고. 이에 따른 경제성 분석을 수행하였다. 노심해석은 현재의 영광 3, 4호기에 장전된 CE형 연료 및 장주기용 개량연료를 초기노심 및 평형 노심에 각각 장전하는 경우에 대하여 수행하였다. 가연성 흡수체는 현재 사용중인 Gadolinia 및 Integral Fuel Burnable Absorber(IFBA) 가연성 흡수체를 사용하여 분석하였다. 그 결과 현재의 CE형 연료에서 사용하는 0.382" 연료봉보다 0.374"의 연료봉이 중성자 경제성 측면에서 유리하며, Gadolinia보다 IFBA가 반경방향 첨두출력 계수의 제어를 쉽게할 수 있슴이 밝혀졌다. 그 외에 열적 여유도 증진을 위한 유량 혼합 날개의 채용과 고연소도를 위한 새로운 피복관 재료의 사용이 요청된다. 이상과 같은 결과는 향후 표준형 원전의 장주기용 개량연료를 위한 개발 방향으로 제시될 수 있다. 제시될 수 있다.

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Comparative Evaluation of the Survival Rates of Zirconia Crown and Stainless Steel Crown for Proximal Caries in Primary Molars: a Retrospective Study (유구치 인접면 우식증 수복 시 지르코니아 전장관과 기성금속관의 생존율 비교 평가: 후향적 연구)

  • Gahui Jeong;Nanyoung Lee;Hyewon Shin;Suhyun Park;Myeongkwan Jih
    • Journal of the korean academy of Pediatric Dentistry
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    • v.50 no.3
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    • pp.307-317
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    • 2023
  • Due to increasing demand for aesthetics, zirconia crowns have become a popular choice for treating primary molars. However, there is limited literature available comparing the survival rates of zirconia crowns with those of other restorative materials. The objective of this study was to compare the 36-month survival rates of zirconia crowns and stainless steel crowns for proximal caries, as well as to analyze failure types associated with each crown type. Electronic medical records and radiographs of 1,061 primary molars from 498 patients treated with 2 types of prefabricated crowns at Chosun University Dental Hospital and 2 private dental clinics between 2017 and 2019 were collected and analyzed. The survival rate of zirconia crowns was found to be lower compared to that of stainless steel crowns. Regarding the groups without pulp treatment, the survival rate of stainless steel crowns was significantly higher than that of zirconia crowns. However, in the groups that received pulp therapy, no significant difference in the survival rates was observed between the two preformed crowns. Notably, abnormal root resorption or periapical lesions were identified as the primary cause of restorative failure in stainless steel crowns, whereas loss of restoration was the predominant cause in zirconia crowns. This study holds valuable implications for clinicians when selecting preformed crowns for primary molars.

The Localization of Lectin Receptors in the Tissue of the Paragonimus westermani (폐흡충조직내 Lectin(WGA) 수용체의 분포)

  • Kim, Soo-Jin;Nahm, Heun-Woo;Lee, Joon-Sang;Joo, Kyung-Whan
    • Applied Microscopy
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    • v.30 no.1
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    • pp.101-111
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    • 2000
  • In this study, the distribution of lectin receptors in Paragonimus westermani tissue was explored using colloidal gold label complexed with lectin WGA purified from wheat germ (Triticum vulgare). The lectin WGA gold complex, shown to recognize GlcNAc (N-acetylgalactosamine) and NeuNAc (N-acetylneuraminic acid) regions, was applied to detect binding sites in Lowicryl HM 20 sections viewed under electron microscope. Labeled sections of the metacercaria revealed gold particles specifically distributed on the tegumental syncytium and lamella of the excretory canal. Labeling of young adult tissue was then quantified and compared to that of adult worm tissue. Adult worm tissue sections resulted in specific gold particle distribution on the lamella of caecal epithelium and excretory canal. These results indicate that lectin WGA receptors are located in the tegumental syncytium and lamella of the excretory canal of the metacercariae, and in the lamella of the caecum and excretory canal of the young adult and adult. Therefore, the GlcNAc and NeuNAc regions in the tegumental syncytium appear to be functionally associated with cell-recognition and protection from the immune system of the host, and linked with membrane transport and absorption of nutrients in the lamella of the excretaory canal and caecal epithelia.

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Behaviors of Arsenic in Paddy Soils and Effects of Absorbed Arsenic on Physiological and Ecological Characteristics of Rice Plant lll. Effect of Water Management on As Uptake and the Growth of Rice Plant at As Added Soil (토양중(土壤中) 비소(砒素)의 행동(行動)과 수도(水稻)의 비소흡수(砒素吸收)에 의(依)한 피해생리(被害生理) 생태(生態)에 관(關)한 연구(硏究);Ⅲ.물관리(管理)가 수도의 비소흡수(砒素吸收) 및 생육(生育)에 미치는 영향(影響))

  • Lee, Min-Hyo;Lim, Soo-Kill-H
    • Korean Journal of Environmental Agriculture
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    • v.6 no.1
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    • pp.1-6
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    • 1987
  • A pot experiment was conducted to find out the effect of water management on the growth and uptake of arsenic and inorganic nutrients of rice plant at As added soil. The arsenic were added to soil at the levels of As 0, 10, 50, 100 and 150 ppm, respectively. Water management was done with two ways: intermittent irrigation from ten days after transplanting, and continuous submersion until harvest. Higher soil As levels increased As content in plant but reduced growth rate. Aresenic content in plant was considerably reduced with intermittent irrigation compared to continuous submersion. Rice growth showed also same trend. With increasing As levels in soil, N content in plant was increased but P, K, Ca, Mg, $SiO_2$, Fe and Mn content in plant were tend to be decreased. These inorganic nutrients in plant were also much absorbed in continuous submersion compared to intermittent irrigation. Soil pH was slightly increased with increasing As levels in soil while soil Eh has no relationship with soil As levels. On the other hand, soil pH was higher in the treatment of continuous submersion than that of intermittent irrigation but soil Eh showed reverse trend. With increasing As levels in soil, water soluble-As and Ca-As fractions in soil tend to be increased with continuous submersion, but these fractions has no tendency with intermittant irrigation.

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Effect of Duloxetine in Functional Gastrointestinal Disorder : In the Perspective of 'Brain-Gut Axis' (기능성 위장관 장애에서 Duloxetine의 효과 : '뇌-장관 축' 모델을 중심으로)

  • Lee, Sang-Shin;Park, Si-Sung
    • Korean Journal of Psychosomatic Medicine
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    • v.20 no.2
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    • pp.135-138
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    • 2012
  • The pathophysiology of functional gastrointestinal disorder(FGID) is not completely understood, but the importance of the 'Brain-Gut Axis(BGA)' model in FGID is being increasingly recognized. The BGA model is a bidirectional, hard-wired and homeostatic relationship between the central nervous system(CNS) and the enteric nervous system(ENS) via neural, neurohormonal and neuroimmunological pathways. In addition, the BGA model would provide a rationale for the use of psychotropics on FGID. The authors experienced two cases in which duloxetine, a serotonin-norepinephrine reuptake inhibitor, was effective in relieving FGID symptoms as well as psychiatric symptoms such as depression and hypochondriacal anxiety. Therefore we discuss the vignettes from the perspective of BGA theory. Duloxetine showed efficacy in these two patients by reducing visceral hypersensivity (bottom-up regulation) and by relieving depression and anxiety(top-down regulation).

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Absorbing Rate of Solar Irradiation on Glass Evacuated Tube Collectors Depending on the Absorbing Tube Shape (진공관형 태양열 집열기의 집열관 형상에 따른 태양 복사 에너지 흡수량의 변화)

  • Seo, Tae-Beom;Kang, Hee-Dong;Kim, Yong
    • Journal of the Korean Solar Energy Society
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    • v.25 no.1
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    • pp.35-44
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    • 2005
  • The absorbing rate of solar irradiation on the surface of an absorbing tube in a glass evacuated solar collector is numerically investigated. Four different shapes of the absorbing tubes are considered, and the absorbed solar irradiation on the surface is calculated for several distances between the absorbing tubes and the incidence angle of solar beam radiation. From the calculation, it is known that the absorbing rate of solar irradiation on the tube surfaces depends upon the shape and the arrangement of absorbing tube and the incidence angle.

Effects of Hydrophilic Surface Treatment on Evaporation Heat Transfer at the Outside Wall of Horizontal Tubes (친수성 표면처리가 수평관 외벽의 증발열전달에 미치는 영향)

  • 박노성;황규대;강병하;정진택
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.12 no.5
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    • pp.525-532
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    • 2000
  • Evaporation heat transfer characteristics have been investigated experimentally when distilled water is sprayed on the outside wall of horizontal tubes in a evaporator. This problem is of particular interest in the design of evaporator of an absorption system. Hydrophilic surface treatment was employed to increase the wettability on copper tubes. The results indicate that evaporation heat transfer with hydrophilic tubes is shown to be 25-44% higher than that with bare tubes at evaporation pressure of 31.8 Torr(evaporation temperature$ 30^{\circ}C). Evaporation heat transfer rates of hydrophilic treatment tubes are improved substantially, comparing with those of conventional copper tubes in the wide range of operating parameters, such as water inlet temperatures, water mass flow rates and evaporation pressures.

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A Study on the Thermoacoustic Sound Generation by Steep Temperature Gradient (급격한 온도구배에 의한 열음향 발생에 관한 연구)

  • 박태국
    • Proceedings of the Acoustical Society of Korea Conference
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    • 1998.06c
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    • pp.235-238
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    • 1998
  • 파이프의 양 끝단에 심한 온도구배가 형성될 때 음향이 발생한다는 사실은 이미 알려진 사실이다. 본 연구는 열구동식 열음향냉동기를 구현하기 위해서 1단계로 열원에 의한 음향발생을 달성하고자 했다. 이를 위해 1/4 파장의 열음향 발생장치를 설계 및 제작하여 실험에 사용하였다. 열음향 발생기는 직경 3cm, 길이 16cm의 공명관에 가열부, 박판집적체, 고온부 및 저온부의 열교환기로 구성되며 발생음의 기본주파수는 520Hz로 설계하였다. 고온부를 38$0^{\circ}C$로 가열한 결과 열음향발생기의 개구부로부터 1m 떨어진 곳에서 최초 음압측정값이 약 112dB, 음향출력으로 약 1와트에 해당하는 값을 얻었다. 박판집적체에 급격한 온도구배가 형성되면서 주변의 기체가 자발적인 진동을 하여 형성된 음향동력중 일부는 공명관 벽에 흡수되고 일부는 열교환기에서 점성에 의해 소산된다. 따라서 실제로 음향으로 변하는 부분은 이들을 감한 부분인데 실험결과 약 53%의 음향 생성효율을 달성했으며 이는 스위프트 등이 얻었던 결과보다 우수하다.

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Tracheal Rupture Following Double-lumen Endotracheal Tube Intubation -One Case Report- (이중관 기관 삽관후 발생된 기관파열 - 1례 보고 -)

  • 박승일;원준호;이종국
    • Journal of Chest Surgery
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    • v.32 no.8
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    • pp.765-767
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    • 1999
  • Tracheobronchial rupture following tracheal intubation is a rare complication. We experienced a case of tracheal rupture following double-lumen endotracheal tube intubation. A 76 year old female was admitted due to coughing and chest discomfort. The operation was performed with the diagnosis of congenital broncho esophageal fistula. During the operation, accidently the main trachea was ruptured longitudinally. There was no history of surgical trauma. The ruptured trachea was repaired with prolene and monofilament absorbable sutures. The cause of tracheal rupture was suspected overinflation of the cuff. The patient was discharged from the hospital without any significant complications.

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A Biopharmaceutical Study on the Absorptive Effect of Some Compounding Drugs(IV) -Effect on the Writhing Syndrome of Salicylamide Combined with Chlorpheniramine Maleate- (배합약물(配合藥物)의 흡수효과에 관(關)한 생물약제학적(生物藥劑學的) 연구(硏究)(IV) -Salicylamide에 Chlorpheniramine Maleate를 배합투여(配合投與)하였을 경우의 Writhing Syndrome에 미치는 영향(影響)에 관(關)하여-)

  • Chung, Ki-Hwa
    • Journal of Pharmaceutical Investigation
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    • v.5 no.4
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    • pp.32-37
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    • 1975
  • The intentional test of the clinical test on the mouse, which are orally administered salicylamide combined with chlorpheniramine maleate were made by writhing syndrome method of 0.7% acetic acid-saline solution and following effects were found. 1) The cross-over test of writhing syndrome method have intention in case of three days rest after the first examination. 2) The most active rate of salicylamide by administration combined with chlorpheniramine maleate is salicylamide 20mg/kg: chlorpheniramine maleate 20mg/kg (1:1) 3) The most active range of chlorpheniramine maleate used for assistant action of salicylamide is $15mg/kg{\sim}20mg/kg$

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