피리딘 치환제와 2-Bromoacetophenone과의 반응에 대한 속도론적 연구

조영재,김용건,김장열,경진범 한양대학교 이학기술연구소 2000 이학기술연구지 Vol.2 No.

메탄을 용매내에서 2-bromoacetophenone과 피리딘 치환체(3-CH3, 3,5-(CH3)2, H, 3-Cl)와의 반응속도를 여러 온도와 농도 조건하에서 전도도법으로 측정하였다. 이 때 반응속도상수는 온도와 피리딘 농도가 증가함에 따라 증가하였으며, 피리딘 치환체에서 치환기의 전자주게 능력이 클수록 반응속도는 증가하였다. 이들 반응속도상수로부터 활성화 엔탈피, ?H≠, 활성화 엔트로피, ?S≠, Hammett 반응상수, p 및 Bsonsted 상관계수, B를 결정하였다. 이 때 ?H≠는 상대적으로 낮은 양의 값을 갖는 반면, ?S≠는 큰 음의 값을 얻었으며, 친핵체의 치환기 효과인 p와 Bronsted 상관계수인 B는 40℃에서 각각 -2.49 및 0.38의 값을 나타내었다. 이러한 결과로부터 본 반응은 dissociative 이분자성 반응으로 진행됨을 알 수 있었다. Kinetics of 2-bromoacetophenone with substituted pyridines (3-CH3, 3,5-(CH3)2, H, 3-Cl) in methanol have been also studied using conductometric method at various temperatures and concentrations. Rate constants are increased with the increment of both temperature and concentration. They are also increased with more electron-donating ability of substituent in nucleophile. The activation enthalpy, ?H≠, the activation entropy, ?S≠, Hammett reaction constant, p and Bronsted coefficient, B are evaluated from the rate constants. The ?H≠ values are positive relatively small while the ??S≠?values are relatively large, and the corresponding coefficients, p and B are -2.49 and 0.38 at 40℃, respectively. From these results, it could be concluded that this reaction proceeds with the dissociative bimolecular pathway.

자연발화억제제를 활용한 고휘발분 석탄의 가연성 가스 억제에 관한 연구

조영재,이광희,노호성 한국재난정보학회 2021 한국재난정보학회 학술대회 Vol.2021 No.11

본 연구에서는 자연발화억제제를 활용하여 고휘발분 석탄의 가연성 가스 억제에 관한 실험을 수행하였다. 석탄의 자연발화 는 심부에서의 열 축적과 공극률, 저탄 높이, 저탄면의 경사각, 석탄 입자 크기, 대기의 온도, 습도 등이 주요 원인이며, 그중 휘발 분 35% 이상의 역청탄은 자연발화가 상대적으로 용이하다. 이러한 고휘발분 역청탄의 자연발화 시 발생하는 가연성 가스의 증감 유무를 확인하기 위하여 20,000톤의 역청탄을 사용하 였으며, 메틸디에탄올아민 등 6가지 성분이 혼합된 자연발화억제제를 도포하고 55일간 분석하였다. 가연성 가스의 증감 유무 확인을 위하여 FT-IR Spectrum Detector가 사용되었으며, 자연발화억제제 도포에 따른 품질 영향 여부를 확인하기 위하여 Carbon & Sulphur Determinator 580, Parr-6400, TGA-219 등의 공업분석 장비가 동원되었다. 실험 결과, 55일이 경과한 시점 에서의 메탄은 자연발화억제제를 미도포 했을 경우 274.29ppm, 도포된 경우 23.90ppm으로 약 10배 이상의 억제 능력을 나타 내었다. 또한, 자연발화 악취의 원인인 황화수소의 최대치는 실험 1일차로 자연발화억제제 미도포의 경우 14.48ppm, 도포의 경우 2.47ppm으로 약 6배가 감소하였다. 그 외, 석탄의 품질 영향 여부에 대한 실험 결과, 자연발화 억제제를 도포했을 경우 발 열량이 일부 감소하고, Ash 및 탄소가 소량 증가했으나 조업 영향에 상관없는 오차범위인 것으로 분석되었다.

Clinical Practice Guideline of Acute Respiratory Distress Syndrome

조영재,문재영,신인순,김제형,정훈,박소영,김호철,심윤수,이진국,임재민,이석정,리원연,이현정,곽상현,강은경,정경수,최원일 대한중환자의학회 2016 Acute and Critical Care Vol.31 No.2

There is no well-stated practical guideline for mechanically ventilated patients with or without acute respiratory distress syndrome (ARDS). We generate strong (1) and weak (2) grade of recommendations based on high (A), moderate (B) and low (C) grade in the quality of evidence. In patients with ARDS, we recommend low tidal volume ventilation (1A) and prone position if it is not contraindicated (1B) to reduce their mortality. However, we did not support high-frequency oscillatory ventilation (1B) and inhaled nitric oxide (1A) as a standard treatment. We also suggest high positive end-expiratory pressure (2B), extracorporeal membrane oxygenation as a rescue therapy (2C), and neuromuscular blockage for 48 hours after starting mechanical ventilation (2B). The application of recruitment maneuver may reduce mortality (2B), however, the use of systemic steroids cannot reduce mortality (2B). In mechanically ventilated patients, we recommend light sedation (1B) and low tidal volume even without ARDS (1B) and suggest lung protective ventilation strategy during the operation to lower the incidence of lung complications including ARDS (2B). Early tracheostomy in mechanically ventilated patients can be performed only in limited patients (2A). In conclusion, of 12 recommendations, nine were in the management of ARDS, and three for mechanically ventilated patients.

곡률변화가 CFRP 적층쉘의 관통특성에 미치는 영향

조영재,이상훈,김영남,양인영 한국공작기계학회 2004 한국공작기계학회 추계학술대회논문집 Vol.2004 No.-

Currently, carbon-fiber reinforced plastics(CFRP) are widely used in both space and civil aircraft due to their superior stiffness and strength to weight ratios compared to conventional metallic materials. This paper is to study the effects of curvature and stacking sequence on the penetration characteristics of composite laminated shell. And were performed to investigate the penetration characteristics of composite laminated shells by the oblique impact. They are stacked to [0₃/90₃]_(s), [90₃/0₃]_(s) and [0₂/90₃/0]_(s), [90₂/0₃/90]_(s) their interlaminar number two and fore. They are manufactured to varied curvature radius (R=100,150,200㎜ and ∞). When the specimen is subjected to transverse impact by a steel ball, the velocity of the steel ball was measured both before and after impact by determining the time for it to pass two ballistics-screen sensor located a known distance apart. In general, the critical penetration energy interface decrease and slope angle on the impact surface increased. [0₃/90₃]_(s) and [0₂/90₃]_(s) specimens higher than [90₃/0₃]s and [90₃/0₃/90]_(s) specimens.

Pumpless Extracorporeal Interventional Lung Assist를 시행한 중증 호흡부전 1예 -증례 보고-

조영재,서지연,김유정,이재호,이춘택 대한중환자의학회 2012 Acute and Critical Care Vol.27 No.2

Pumpless extracorporeal interventional lung assist (iLA) is a promising respiratory rescue system permitting protective lung ventilation for severe respiratory failure. Herein, we report a case of prolonged iLA support with regards to a patient exhibiting severe hypercapnic respiratory failure. A 51-year-old female patient with metastatic endometrial carcinoma developed progressive hospital-acquired pneumonia and was intubated in order to restore respiratory failure. Despite maximal mechanical ventilator care, her clinical condition deteriorated due to severe respiratory acidosis. The iLA was performed for the management of refractory hypercapnia. The total duration of iLA support was 23 days without any vascular complications, however, she could not survive because of oxygenation failure.

새만금 간척지 주변지역의 중심기능 분석

조영재,최수명,윤용철,김영주 경상대학교 농업생명과학연구원 2007 농업생명과학연구 Vol.41 No.1

交易條件에 따른 輸出商品의 國際競爭强化

趙泳在 원광대학교 무역학과 1983 무역연구 Vol.3 No.-

농촌마을의 공동화와 과소·고령화 현상의 관련성 연구 - 충남 금산군을 중심으로 -

조영재,김두환,조은정 한국농촌계획학회 2015 농촌계획 Vol.21 No.4

The purpose of this study is to investigate how the hollowization in rural villages which causes marginal villages appears in Korean rural villages and whether the hollowization has relation with decrease and aging of population or not. For achieving the research objective, survey was carried out focused on Geumsan-gun. As a result, it confirmed that rural out-migration and rural decline especially in 'people', 'land(economic situation)' and 'community' have being progressed. Also variance analysis and regression analysis were executed with using the number of population and the ratio of people over 65 as dependent variables and using each survey contents(variables) as independent variables. The results of analysis showed that the ratio of people over 65(+), the income level per household(-), the rate of fallow lands(+), the number of empty houses(+), programs for urban-rural interchange(+), and the implementing public projects(+), etc. have a relation with the number of population(-) and the number of population(-), the income level per household(-), the rate of fallow lands(+), the number of empty houses(+), activities of communities(+), and the implementing public projects(+), etc. have a relation with the ratio of people over 65(+) (+: increase, -: decrease). So the hollowization in people', 'land(economic situation)' and 'community' has direct relation with decrease and aging of population in rural areas.

충남논단 : 충청남도의 농촌개발사업 추진실태에 관한 공무원 및 전문가 의식 분석

조영재,박지혜 충남발전연구원 2009 열린충남 Vol.48 No.-

굴곡성 기관지경으로 치료 후 호전된 2개월 영아에서의 흡인성 폐렴

조영재,함세창,김우경,김영균,박용원,이혜경 인제대학교 백병원 2002 仁濟醫學 Vol.23 No.4

The flexible bronchoscopy is not frequently used in children as in adults due to many causes. However the role of bronchoscopy in children is important in respect of diagnosis and treatment. We have done with flexible bronchoscopy for the purpose of diagnosis and treatment in a two-month-old infant with pneumonia and atelectasis. The lipid-laden alveolar macrophage(LLAM) index was 227/400. We thought the aspiration pneumonia of the patient resulted from his mother's abnormal feeding posture. After the bronchoscopy and washing, the radiologic findings and clinical symptoms were improved. We recommended the feeding position to the patient's mother and he has been well-being state afterwards.