• 제목/요약/키워드: Delayed Appearance

검색결과 97건 처리시간 0.025초

소형 오리멀젼 보일러의 연소특성 연구 (Study on the Combustion Characteristics of a Small-Scale Orimulsion Boiler)

  • 김혜숙;신미수;장동순;최영찬;이재구
    • 대한환경공학회지
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    • 제27권10호
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    • pp.1081-1089
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    • 2005
  • 본 연구에서는 기존에 중유를 사용하는 상용보일러에서 오리멀젼 연료의 활용 가능성을 평가하기 위하여 소형 보일러에서 오리멀젼 연료의 기본적인 연소특성을 실험과 더불어 수치해석하였다. 오리멀젼의 주요 연소특성은 최고 화염온도가 버너로부터 $20{\sim}30\;cm 뒤쪽에 나타나는 화염지연현상과 비교적 넓게 분포하는 화염의 형태로 이는 오리멀젼 제조과정에서 포함된 높은 수분함량과 미세한 수부액적으로 이한 미소폭발 현상에 기인한다. 오리멀젼 연료의 연소특성에 미치는 영향을 평가하기 위하여 연료공급량, 무화유체의 종류, 그리고 계산에 사용된 현상학적인 복사모델과 같은 중요한 설계 및 운전인자에 대한 일련의 변수연구를 수행하였다. 연소특성인 최고 화염온도 지연현상은 연료공급 속도를 조절함으로써 어느 정도 저감시킬 수 있었으며 연소생성물로 CO와 $SO_2$ 그리고 NO가스의 연소로 내 발생특성을 평가하였다. 또한 무화용 유체로 증기를 사용하였을 경우 로내 연소상태는 무화용 공기에 비해 안정화 되고 고온영역이 감소되는 결과를 보였다. 일반적으로 본 연구에서 수행한 실험조건에 대한 수치해석 결과는 물리적으로 일관성 있는 결과를 제시하였으나 오염물질 생성농도에 대한 보다 정확한 예측을 위해서는 추후 현상학적인 모델개선을 필요로 한다. 결국 본 연구로부터 개발된 컴퓨터 프로그램은 기존의 상용화 중유 보일러에서 오리멀젼 연료로 대체 사용시 개선사항 및 유용한 운전 자료를 제공할 것으로 판단된다.

배주배양에 의한 Nicotiana rustica와 N. tabacum의 잡종식물 육성 (Production of Sexual Hybrids Nicotiana rustica X N. tobacum via in vitro Culture .of Fertilized ovules.)

  • 최상주;홍병희
    • 한국연초학회지
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    • 제14권1호
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    • pp.3-11
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    • 1992
  • The present study examined various environmental and cultural media conditions for in vitro "rescue" of cross-fertilized ovules formed through sexual crosses between Nicotiana rustica and N. tabacum cv. BY4. The response ovules to two cultural procedures was compared; ovules were cultured either separately or left attached to the placenta. Total yield of seedlings and percent of normal seedlings were increased by culturing individual ovules separately, rather than on excised placenta. Total yield of seedlings and number of normal seedlings were produced following in vitro culture of individual fertilized ovules of N. rustica X M tabacum cv. BY4 at four days post-pollination on NN medium containing 2% sucrose. In the in vitro culture of fertilized ovules, high sucrose concentration increased the frequency of seedlings of abnormal appearance. Therefore, sucrose should be supplied to developing ovules at gradually decreased concentrations. Culture of fertilized ovules from three to eight days after pollination gave increased number of seedlings, but with delayed cultral time the number of morphologically normal seedling were decreased. Hybrids were uniform in appearance and showed vegetative heterosis but flower characteristics were generally intermediate between those of the parents. All hvbrids evaluated were self-sterile.f-sterile.

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일측성 유방절제술이 척추측만증을 일으키는가? (0Does Unilateral Mastectomy Cause Scoliosis?)

  • 이성욱;이택종;이성우
    • Archives of Plastic Surgery
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    • 제35권3호
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    • pp.279-282
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    • 2008
  • Purpose: It is known that the chronic absence of unilateral breast can cause spine curvature. The artificial breast manufactures take up the position of that possibility. This study was designed to evaluate the influence of the mastectomy on the spine and appearance of scoliosis among women who wanted delayed breast reconstruction. ted delayed breast reconstruction. Methods: The study population consisted of 47 women who underwent delayed breast reconstruction at our Department of Plastic Surgery from April 2001 to May 2007. The whole spine anteroposterior and lateral X-ray was taken to evaluate the Cobb's angle. As a general rule a Cobb angle of 10 is regarded as a minimum angulation to define scoliosis. We evaluated Cobb's angle and drew a correlation between the duration of the mastectomy state and the weight of the mastectomy specimen. Results: There were no family history of scoliosis, and no numbness or weakness in the upper or lower extremities. They had normal reflex and experienced no tenderness of the perispinal area. The Spearman Correlation Coefficient between Cobb's angle and the period that took time from the mastectomy to the X-rays and analysis between Cobb's angle and specimen weight was 0.032 and-0.115. there were no correlation between Cobb's angle and time, or between Cobb's angle and specimen weight. Conclusion: lthough the patients attribute their back pain and distorted posture to having received an one-sided mastectomy, it is unlikely that one-sided mastectomy causes spinal deformity and scoliosis.

Leaf Senescence in a Stay-Green Mutant of Arabidopsis thaliana: Disassembly Process of Photosystem I and II during Dark-Incubation

  • Oh, Min-Hyuk;Kim, Yung-Jin;Lee, Choon-Hwan
    • BMB Reports
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    • 제33권3호
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    • pp.256-262
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    • 2000
  • In this study the disassembly process of chlorophyII (ChI)protein complexes of a stay-green mutant (ore10 of Arabidopsis thaliana) was investigated during the dark incubation of detached leaves. During this dark-induced senescence (DIS), the Chi loss was delayed in the mutant, while the photochemical efficiency of photosystem II (PSII) or Fv/Fm was accelerated when compared with the wild type (WT) leaves. This indicates that the decrease in Fv/Fm is a separate process and not causally-linked to the degradation of Chi during DIS of Arabidopsis leaves. In the native green gel electrophoresis of the Chi-protein complexes, which was combined with an additional twodimensional SDS-PAGE analysis, the delayed senescence of this mutant was characterized by the appearance of an aggregate at 1 d or 2 d, as well as very stable light harvesting complex II (LHCII) trimers until 5 d after the start of DIS. The polypeptide composition of the aggregates varied during the whole DIS at 5 d. Dl protein appeared to be missing in the aggregates. This result supports the idea of a faster depletion of functional PSH in the mutants compared with WT, as suggested by the earlier reduction of Fv/Fm and the stable Chl a/b ratio in the mutants. At 5 d, the WT leaves also often showed aggregates, but the polypeptide composition was different from those of ore10. The results presented suggest that the formation of aggregates, or stable LHCII trimers in the stay-green mutants, is a way to structurally protect Chi-protein complexes from serious proteolytic degradation. Detailed disassembly processes of Chi-protein complexes in WT and ore10 mutants are discussed.

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消風散과 加味消風散이 免疫反應 및 抗 알레르기에 미치는 影響 (The Effects of Sopungsan and Gamisopungsan on Immune Response and the Anti-Allergic Reaction to Rats and Mice)

  • 김중호;채병윤
    • 한방안이비인후피부과학회지
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    • 제4권1호
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    • pp.1-22
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    • 1991
  • The object of this research is to find out the clinical effects of Sopungsan and Gamisopungsan on Immune response and the An1i-allergic reaction to rats and mice. The results obtained are as follows: 1. Both sopungsan and Gamisopungsan have a tendency to decrease on the delayed type hypersensitivity response in methotrexate treated mice, but are not recognized as having significance. 2. Both Sopungsan and Gamisopungsan reveal the increasing effects with significance on the hemagglution titer in mice. 3. Gamisopungsan reveals the increasing effect with significance on the hemolysin titer in mice. 4. Both Sopungsan and Gamisopungsan have a tendency to increase on the appearance of Rosette forming cells in mice, but are not recognized as having significance. 5. Both Sopungsan and Gamisopungsan reveal the increasing effects with significance on phagocytic index K and a in mice 6. Sopungsan reveals the decreasing effect, on the homologous passive cutaneous anaphylaxis in rats provoked by the IgE-like antibody aganist egg white albumin. 7. Gamisopungsan reveals the decreasing effect with significance on vascular permeabi1ity response to intradermal histamin in rats. 8. Sopungsan reveals the decreasing effect with significance, on vascular permeability response to intradermal serotonin in rats. 9. Both Sopungsan and Gamisopungsan reveal the decreasing effects with significance on the delayed type hypersensitivity response to picryl chloride in mice. 10. Both Sopungsan and Gamisopungsan reveal the decreasing effects with significance on the delayed type hypersensitivity response to sheep red blood cell in mice. According to the above results, Sopungsan and Gamisopungsan are concluded to have the increasing effect of immunity and anti-allergic reaction.

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개에서 골절의 지연유합에 대한 rhBMP-2의 임상적 적용 2례 (Clinical Application of Recombinant Human Bone Morphogenetic Protein-2 for Delayed Fractures in Dogs)

  • 김재경;김세은;고아라;김승현;심경미;배춘식;최석화;강성수
    • 한국임상수의학회지
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    • 제29권5호
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    • pp.412-415
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    • 2012
  • 1년령의 중성화된 수컷 요크셔테리어와 7년령의 암컷 푸들이 골절의 지연유합으로 내원하였다. 요크셔테리어의 경우 오른쪽 요골과 척골의 원위부가 골절되었고, 푸들의 경우 왼쪽 경골과 비골의 원위부가 골절되었다. 두 환자에서 신체검사 및 방사선검사를 통해 골절의 유합이 지연되고 있음을 확인하였다. 골절부는 금속판 및 나사못으로 고정시키고 자가해면질골을 골절 틈새에 이식하였다. 또한 빠른 골유합을 위해 $20{\mu}g$의 rh-BMP 2 가 포함된 matrigel을 골절부에 주입하였다. 수술 후 방사선검사를 통해 골절부의 치유 상태를 확인하였다. 장기간의 방사선검사에서 두 마리 모두 빠른 골유합을 보였다. 첫 증례에서는 방사선사진상에서 2주째에 요골과 척골 골절 틈새에 골밀도가 증가하였다. 20주째에는 골절선이 더 이상 관찰되지 않았으며, 정상 외관을 회복하였다. 두 번째 증례에서는 방사선사진상에서 11주째에 골절 치유가 진행되고 있음이 확인되었다. 이 두 증례 모두 예상한 것보다 골절의 치유가 빠르게 일어났다. 따라서 rh-BMP 2와 matrigel은 지연유합된 골절의 치유를 촉진하는데 효과가 있다고 생각된다.

Evolution of Social Life in Wood-Eating Cockroaches (Cryptocercus spp.) : Effects of the Winter Climate on the Evolution of Subsociality

  • Park, Yung-Chul;Choe, Jae-Chun
    • Journal of Ecology and Environment
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    • 제31권2호
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    • pp.97-105
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    • 2008
  • Subsocial behavior of the genus Cryptocercus cockroaches has been believed as primitive traits of termite eusociality. Thus, it has been believed that understanding Cryptocercus subsociality is a pre-requisite stage to infer evolutionary route of the eusociality in termites. Woodroaches of Cryptocercus are also well known because of its peculiar characteristics including adults living monogamously in pairs, semelparous reproduction, xylophagy, obligatory association between adults and their offspring, slow development, and anal trophallaxis by adults. Based on the previously accumulated data, we try to understand two major components of Cryptocercus life history, development and reproduction. We hypothesize that harsh winter and length of winter might be one of the main causes driving the appearance of the delayed development and semelparous reproduction in Cryptocercus life history.

상악골에 발생한 원발성 골내암종 (Primary intraosseous carcinoma occurring in the maxilla)

  • 김미자
    • Imaging Science in Dentistry
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    • 제34권1호
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    • pp.49-54
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    • 2004
  • Primary intraosseous carcinoma (PIOC) is a rare odontogenic carcinoma defined as a squamous cell carcinoma arising within a jaw having no initial connection with the oral mucosa, and presumably developing from residues of the odontogenic epithelium. A 56-year-old patient who complained of delayed healing after extraction of upper left central incisor visited our department. The conventional radiographs showed a bony destructive lesion with ill-defined margin and moth-eaten appearance. On the computed tomographic images, the lesion perforated the labial cortex of alveloar bone, elevated the left nasal floor superiorly, and perforated partially both nasal floor. The magnetic resonance images showed low signal intensity at T2 and Tl weighted images at the area and adjacent soft tissue. Histologically, there were irregular epithelial islands with cell atypia, nuclear hyperchromatism, pleomorphism, atypical mitosis. The final diagnosis was PIOC.

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주기적 상류 후류의 익 경계층과 손실에 미치는 영향에 대한 실험적 연구 (Experimental Study on the Effects of Upstream Periodic Wakes on Aerofoil-Boundary Layer and Loss)

  • 임인원;조강래;주원구
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2001년도 춘계학술대회논문집E
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    • pp.661-667
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    • 2001
  • This paper is concerned with the effects of periodically approaching upstream wakes on cascade-flow and loss. The reduced frequency of the periodic wakes was varied in the narrow range from 0.5 to 0.7. According to a wake-passing through the cascade, two velocity deficits appear near the boundary layer contour in the downstream from about 60% chord-length. The first velocity deficit is caused by a periodic wake and the second one appears after some delayed time. The second velocity deficit may be interpreted as the results of reattachment of flow-separation. The higher reduced frequency decreases the duration time of separation appearance and the lesser loss of aerofoil is resulted.

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Aerodynamic Performance Improvement by Divergent Trailing Edge Modification to a Supercritical Airfoil

  • Yoo, Neung-Soo
    • Journal of Mechanical Science and Technology
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    • 제15권10호
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    • pp.1434-1441
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    • 2001
  • A computational study has been performed to determine the effects of divergent trailing edge (DTE) modification to a supercritical airfoil in transonic flow field. For this, the computational result with the original DLBA 186 supercritical airfoil was compared to that of the modified DLBA 283. A wavier-Stokes code, Fluent 5. 1, was used with Spalart-Allmaras's one-equation turbulence model. Results in this study showed that the reduction in drag due to the DTE modification is associated with weakened shock and delayed shock appearance. The decrease in drag due to the DTE modification is greater than the increase in base drag. The effect of the recirculating flow region on lift increase was also observed. An airfoil with DTE modification achieved the same lift coefficient at a lower angle of attack while giving a lower drag coefficient. Thus, the lift-to-drag ratio increases in transonic flow conditions compared to the original airfoil. The lift coefficient increases considerably whereas the lift slope increases just a little due to DTE modification.

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