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      • 디에틸아민과 브롬화벤질류의 反應速度論

        구본기,최성용,김덕기,김영철 漢陽大學校 自然科學硏究所 1997 自然科學論文集 Vol.16 No.-

        아세토니트릴 용매내에서 파라치환 브롬화벤질류(p-CH₃, p-H, p-NO₂)와 디에틸아민의 반응을 고진공하에서 온도(20, 25, 30℃) 변화에 따라 속도론적으로 연구하였다. 이때 반응속도상수는 온도가 증가함에 따라 증가하였으며, 또한 기질에 전자 주게 치환체(p-CH₃)가 치환된 경우 증가하였다. 이들 반응속도상수로부터 활성화에너지(Ea), 활성화엔탈피(???), 활성화엔트로피(???), 활성화자유에너지(???) 및 Hammett 반응상수 ρ를 구하였으며, 전반적인 반응메카니즘은 dissociative ??? 반응으로 진행됨을 알 수 있었다. The reaction rates of p-substituted benzyl bromides(p-CH₃, p-H, p-NO₂) with diethylamine have been measured by conductivity method in acetonitrile, and pseudo-first order and second order rate constants are determined at 20℃, 25℃, and 30℃. The rate constants are increased with a function of temperatures and are further increased by introducing the electron donating substituents in substrates. The activation energies(Ea), activation parameters(??????) and Hammett ρ values are calculated from the rate constants and, generally, the results of these studies show a greater degree of bond breaking than bond formation in the transition state.

      • KCI등재
      • 실리카 도파로형 WDM 광 필터의 설계 및 해석에 관한 연구

        최대필,문성욱,정영철,신장욱,정명영,최태구 광운대학교 신기술연구소 1997 신기술연구소논문집 Vol.26 No.-

        본 논문에서는 Mach-Zehnder 간섭기로 구성된 1×4 필터와 성형결합기로 구성된 5×5 광도파로 격자 라우터를 BPM CAD TOOL을 이용하여 설계하였고 최적화 하였다. 마스크 레이아웃을 효율적으로 실현하기 위한 전체 도파구조를 설계하였다. BPM 전산모사를 통해 설계된 소자의 WDM 특성을 0.8 nm(100 ㎓)와 8.0 nm(1000 ㎓)의 채널간격에 대해서 살펴보았다. 설계된 소자는 두가지 채널간격 모두에 대하여 3.5dB 이내의 잉여손실, 0.5dB 이내의 균일성과 -22dB 이내의 누화(crosstalk)특성을 보임을 확인하였다. In this paper, we designed and optimized 1×4 WDM Filter composed of Mach-Zehnder Interferometer and 5×5 Waveguide Grating Router(WGR) composed of two star couplers. The overall guiding structure is designed to realize the mask layout efficiently. Through the BPM simulation, we demonstrated WDM characteristics of these devices with 0.8 nm and 8.0 nm channel-spacing. It is shown that the excess loss is less than 3.5dB, uniformity less than 0.5dB and the crosstalk smaller than –22 dB for both the channel spacings.

      • KCI등재후보

        골아세포 MC₃T₃-E₁의 증식과 기능에 Insulin Like Growth Factor Ⅰ, Ⅱ 및 부갑상선 호르몬이 미치는 영향

        윤현구,정호연,양인명,김성운,김진우,김광원,김영설,최영길,서광식 대한내과학회 1992 대한내과학회지 Vol.42 No.1

        MC₃T₃-E₁골아세포군을 이용하여 IGF-Ⅰ과 Ⅱ를 투여하고 DNA합성과 골아세포기능을 측정하기 위해 PTH에 대한 C-AMP반응정도, alkaline phosphatase 활성도를 측정하여 다음과 같은 결과를 얻었다. 1) IGF-Ⅰ과 Ⅱ는 모두 DNA합성이 어느 농도까지는 증식효과를 나타내지만 그 이후에는 억제되는 양상을 보였다. 2) PTH에 대한 골아세포의 C-AMP반응으로 증가되었지만 IGF-Ⅰ과 Ⅱ의 투여시 농도변화에 따른 의미있는 변화는 없었다. 3) 본 실험의 조건에서 alkaline phosphatase 활성도는 증가되지 않았다. 이상의 결과로 MC₃T₃-E₁ 골아세포에 IGF-Ⅰ과 Ⅱ는 세포의 증식을 자극하여 PTH는 C-AMP생성을 촉진하는 효과가 있었다. The effect of insulin-like growth factor (IGF) Ⅰ and Ⅱ on cloned MC₃T₃-E₁ cells that had osteoblastic activity was examined by [³H] thymidine incorporation into DNA, cyclic AMP responsiveness to parathyroid hormone (PTH), and alkaline phosphatase activity. IGF Ⅰ and Ⅱ stimulated the growth and proliferation of osteoblastic cells at 20ng/㎖ and 50ng/㎖, respectively. We next examined the effect of IGF-Ⅰ and Ⅱ on the expression of osteoblastic activity. Adenylate cyclase response of PTH to IGF-Ⅰ and Ⅱ-treated cells showed maximal stimulation at 10 and 50㎚PTH, respectively, but IGF Ⅰ and Ⅱ induced limited activity of osteoblastic function. In conclusion, IGF-Ⅰ and Ⅱ were potent stimulators to the growth of osteoblastic cells but did not have an immediate effect on expression of osteoblastic function in this experiment.

      • 복막투석복막염 환자에서 발생한 창자벽공기증 1예

        정선영,나지훈,최윤정,고성애,조규향,박종원,도준영,윤경우 영남대학교 의과대학 2009 Yeungnam University Journal of Medicine Vol.26 No.1

        Peritonitis is a serious problem in patients undergoing peritoneal dialysis. Rarely pneumatosis intestinalis can occur as a complication of this infectious process. Pneumatosis intestinalis is a potential life threatening condition with a challenging management. The mortality of peritoneal dialysis patients with pneumatosis intestinalis secondary to mesenteric ischemia is almost 100%. We describe a rare case of pneumatosis intestinalis in a peritoneal dialysis patient who developed Staphylococcus aureus peritonitis which was initially treated with appropriate antibiotics. Since initial response to therapy was not achieved, an abdominal computerized tomography was done which revealed a pneumatosis intestinalis. A laparotomy was performed and small bowel necrosis was seen. A segmented resection with ileostomy, jejunostomy was done. Though surgical treatment was performed, the patient died in 2 weeks after admission. Pneumocystitis intestinalis in peritoneal dialysis peritonitis is a uncommon complication which requires prompt evaluation to rule out mesenteric ischemia as it carries a high mortality and its management will be surgical.

      • 제주도 지하수의 전기비전도도와 염소이온의 지역별 변화 양상

        문영석,고기원,최영찬,고용구 濟州大學校海洋硏究所 1995 해양과환경연구소 연구논문집 Vol.19 No.-

        The specific electrical conductivity and the chloride contents were monitored at 98 sits in Cheju Island during two years (1994.2∼1995.11) to the purpose of characterized to regional variations of its elements. The areas of east and west were characterized by both higher elements contain than south and north area. Chloride and specific electrical conductivity values from Kimyoung to Shinhung areas showed more than 100㎎/ℓand 400 μmohs/㎝, respectively. Also west areas relatively high values of both elements were derived from agricultural practice and feeding cattle. However, the difference of difference of these areas indicated that the groundwater environments were different.

      • KCI등재

        McNamara분석법에 의한 Ⅲ급 부정교합 아동의 두부방사선 계측학적 연구

        양규호,김지영,최남기 대한소아치과학회 2001 大韓小兒齒科學會誌 Vol.28 No.3

        정상교합아동과 비교적 조기치료가 요구되는 Ⅲ급 부정교합을 갖는 성장기 아동에서 측모 두부 방사선 계측치의 평균치를 산출하여 진단 및 치료계획 수립에 도움이 되고자 전남대학교병원 소아치과에 내원한 7세에서 9세사이의 17급 부정교합 아동 83명과 안모가 단정하고 정상교합을 갖는 광주지역 초등학생 84명을 대상으로 측모 두부 방사선촬영을 하여 McNamara분석법을 이용한 계측치를 비교 분석하여 다음과 같은 결론을 얻었다. 1. 남아에서 정상교합자와 Ⅲ급 부정 교합자간의 계측치에서 Effective maxillary length.Maxillomandibular differential, Facial axis, Nasion perp to pogonion, Point A perp to Mx 1, A-Pog line to Mn 1의 항목이 유의성 있는 차이를 나타내었다(p<0.01) 2.여아에서 정상교합자와 Ⅲ급 부정교합자간의 계측치에서 Nasion Perp. to Point A(p<0.05), Erective Mandibular lengh, Effective Maxillary lengh, Maxillomandibular differential, Mandibular plane angle, Point A perp to Mx 1, A-Pog line to Mn 1의 항목이 유의성 있는 차이를 나타내었다(p<0.01). 3. Effective Mandibular lengh는 남아에서 정상교합자와 Ⅲ급 부정교합자간에 차이가 없었으나, 여아에서는 유의한 차이가 있었다(p<0.01) 그러나 Effective Maxillary lengh는 Ⅲ급 부정교합자가 남녀 모두에서 정상교합자보다 유의성 있게 짧았다(p<0.01) . 4. Anterior lower facial height는 남녀 모두 정상교합자와 Ⅲ급 부정교합자의 비교에서 유의한 차이가 없었다 7. 남아와 여아의 계측치 비교에서 Anterior lower facial height와 Mandibular plane angle은 정상교합자와 Ⅲ급 부정 교합자 모두에서 유의한 차이가 있었다(p<0.01) . In the growing children with normal occlusion and class Ⅲ malocclusion who need the early treatment to be helped to diagnose and to set up treatment plan by calculating the mean values of the lateral cephalometric measurements, cephalometric measurements by McNamara alalysis were achieved and compared on both the 84 elementary school children with normal occlusion and 83 class Ⅲ malocclusion children at the age of 7 to 9 in Kwangju city and the results were as follows : 1. On the boys group, between normal occlusion and class Ⅲ malocclusion, Effective maxillary length, Maxillomandibular differential, Facial axis. Nasion perpendicualr to pogonion, Point A perp to Mx 1, and A-Pog line to Mn 1 showed significant differences(p<0.05) . 2. On the girls group, between normal occlusion and class Ⅲ malocclusion significant differences were shown in Effective Maxillary length, Maxillomandibular differential, Mandibular plan angle, Nasion perpendicular to Point A, Point A perp to Mx 1 A-Pog line to Mn 1(p<0.01). 3 There were no significant differences between normal occlusion and class Ⅲ malocclusion of boys group but siginificant differences between them of girls group in Effective mandibular length(p<0.01), On the boys and girls group, Effective maxillary length of class Ⅲ malocclusion was shorter than that of normal occlusion. 4. There were no significant differences between normal occlusion and class Ⅲ malocclusion both in boys and girls at Anterior lower facial height. 5. There were significant differences between boys and girls both in class Ⅲ malocclusion and normal occlusion at Anterior lower facial height and Mandibular plane angle(p<0.01) .

      • 만성 심부전환자의 혈액에서 측정한 Tumor necrosis factor-α 및 Interleukin-6의 임상적 의의

        김명구,김성구,박상호,한대희,강진환,변정득,심규혁,최병조,방덕원,온영근,현민수,권영주 순천향의학연구소 2001 Journal of Soonchunhyang Medical Science Vol.7 No.2

        Background and objectives: Many conditions are responsible for the pathophysiology and progressive mechanisms of congestive heart failure. More recently, it has also become evidence that another class of biologycally activated molecules generically reffered to as cytokine these are also over expressed in congestive heart failure. Therefore, the purpose of this study was to measure concentrations of tumor necrosis factor-α(TNF-α), interleukin-6(IL-6) in mild to severe symptoms of heart failure and compare their values with those found in normal control and analysed correlation relationship between cytokine level, clinical findings and hemodynamic indicies. Subjects and Methodology: Levels of TNF-α and IL-6 were measured on pulmonary artery during cardiac catheterization in heart failure patients(n=32) and normal subjects(n=8) as well as physical examination and echocardiogram. Cytokines assay were performed on plasma using commercially available ELISA(Enazyme-Linked Immunosorbent Assay) kits. Results: Although the levels of TNF-α and IL-6 tend to increase in congestive heart failure group, the cytokines level was not made significantly statistical difference between congestive heart failure group and controls. When analyzing the correlation between the levels of PCWP(pulmonary capillary wedge pressure) and cytokines(TNF-α, IL-6), respectively, there were statistically significant correlation coefficient 0.32,(p<0.05), 0.39(p<0.01). The cytokine IL-6 and pressure of pulmonary artery were significant correlation.(correlation coefficient 0.36, p<0.02) More significantly, there was correlated with TNF-α and IL-6.(correlation coefficient 0.57, p<0.001) Conclusions: There was tended toward high concentration of TNF-α & IL-6 in congestive heart failure and significant difference for PCWP between TNF-α & IL-6, thus may be correlated with development and progression in congestive heart failure.

      • 2,4-D 處理가 'Harcot' 살구와 '美白' 복숭아의 果實 成熟과 品質에 미치는 影響

        윤철구,김영호,임상철,김학현,이철희,최관순,김선규 충북대학교 농업과학기술연구소 1999 農業科學硏究 Vol.16 No.-

        Effect of 2,4- D application on the fruit maturity and quality of 'Harcot' apricot and 'Mibaek' peach was examined. Leaf area of 'Harcot' apricot was not affected by 2,4-D while that of 'Mibaek' peach was increased by 35mg · L-1 2,4-D. Application of 2,4-D at 35mgㆍL-1 increased the fruit weight of both species, and that of 'Harcot' was doubled. Soluble solids content of 'Harcot' was decreased by 2,4-D while that of 'Mibaek' was not affected. Fruit maturity of 'Harcot' and 'Mibaek' was enhanced for respective 4 and 1 day by 2,4-D application. Percent fruit cracking of 'Harcot' apricot was decreased by 35mg · L-1 2,4-D.

      • 지베렐린과 에세폰의 葉面撒布가 '美白' 복숭아의 熟期와 品質에 미치는 影響

        김영호,윤철구,임상철,김학현,이철희,최관순,김선규 충북대학교 농업과학기술연구소 1999 農業科學硏究 Vol.16 No.-

        In order to obtain the basic data for artificial maturity control of 'Mibaek' peach, GA and ethephon were foliar sprayed 4 weeks prior to harvest, and their effects on fruit maturity and quality were examined. GA and ethephon tended to decrease the fruit weight except 100mg ㆍ L-1 GA+50 to 100mg · L-1 ethephon treatment. GA increased the fruit firmness, and ethephon at higher concentration increased the fruit drop. Harvest date was advanced for 7 to 8 days by ethephon while was delayed for 6 to 8 days by GA treatment, regardless of concentration.

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