β-lactam 抗菌劑의 作用機轉

林定圭 대한감염학회 1982 감염 Vol.14 No.1

β-lactam 항인제란 β-위치에 lactam(NH-CO)환을 가지고 있는 항인제를 말하며 penicillin과 cephalosprin 계항인제를 말한다. penicillin 의 화학구조는 Fig. 1에서 보는바와 여히 ⓐ thiazolidine 환에 ⓑ β-lactam 환이 붙어 있으며 이 β-lactam 환에 ⓒ 유리 amino기가 있고 이 유리 amino기에 R_1 acidic radical이 붙어있다. 이 acidic radical R_1 에 따라 penicillin의 생물학적 여러 활성의 차이를 갖게된다.

WBI 활용 과학 학습지도 자료 개발 및 적용

임정규 강원과학교육연구회 2002 세미나 Vol.2002 No.1

胃捻轉症

林晶圭(Jeung Kyu Lim),裵元吉(Won, Kil Pai) 대한외과학회 1973 Annals of Surgical Treatment and Research(ASRT) Vol.15 No.4

Al-CNT 복합펠렛의 계면반응에 미치는 마그네슘 첨가 및 제조 조건의 영향

임정규 ( Jung Kyu Lim ),최순열 ( Soon Yool Choi ),최경환 ( Kyong Hwan Choe ),김상섭 ( Sang Sub Kim ),조규섭 ( Gue Serb Cho ) 대한금속재료학회(구 대한금속학회) 2013 대한금속·재료학회지 Vol.51 No.5

In the present study, Al-CNT pellets were investigated to understand the effect of Mg addition and manufacturing conditions on the interfacial reactions between Al and CNTs in Al-CNT pellets. The pellets were heated and held at 700 ℃ and 800 ℃ for 2 hours under nitrogen (N2) atmosphere. To confirm the reactions between Al and CNT in the pellets under different manufacturing conditions, the microstructures were observed by optical microscopy (OM) and field emission scanning electro microscopy (FESEM). And, the composition and reaction phases were analyzed by energy dispersive X-ray spectroscory (EDXS) and X-ray diffractometry (XRD). The presence of oxidation products and Mg on the surface of Al powder in the pellets appeared to prevent the formation of Al4C3. But, Al4C3 reaction products were increased due to the high temperature of 800 ℃, which produced a high amount of reduced aluminium and increased the reaction areas between Al and CNT. The Al-CNT pellets compacted under air atmosphere prohibited the reaction between Al and CNT because of the high amount of oxidation products, such as MgO and MgAl2O4.

Cefoperazone(T-1551)의 약리학적 연구

임정규,홍사악,박찬웅,김명석,서유헌,신상구,김용식,김혜원,이정수,장기철,이상국,장우현,김익상,Lim J.K.,Hong S.A.,Park C.W.,Kim M.S.,Suh Y.H.,Shin S.G.,Kim Y.S.,Kim H.W.,Lee J.S.,Chang K.C.,Lee S.K.,Chang K.C.,Kim I.S. 대한약리학회 1980 대한약리학잡지 Vol.16 No.2

The pharmacological and microbiological studies of Cefoperazone (T-1551, Toyama Chemical Co., Japan) were conducted in vitro and in vivo. The studies included stability and physicochemical characteristics, antimicrobial activity, animal and human pharmacokinetics, animal pharmacodynamics and safety evaluation of Cefoperazone sodium for injection. 1) Stability and physicochemical characteristics. Sodium salt of cefoperazone for injection had a general appearance of white crystalline powder which contained 0.5% water, and of which melting point was $187.2^{\circ}C$. The pH's of 10% and 25% aqueous solutions were 5.03 ana 5.16 at $25^{\circ}C$. The preparations of cefoperazone did not contain any pyrogenic substances and did not liberate histamine in cats. The drug was highly compatible with common infusion solutions including 5% Dextrose solution and no significant potency decrease was observed in 5 hours after mixing. Powdered cefoperazone sodium contained in hermetically sealed and ligt-shielded container was highly stable at $4^circ}C{\sim}37^{\circ}C$ for 12 weeks. When stored at $4^{\circ}C$ the potency was retained almost completely for up to one year. 2) Antimicrobial activity against clinical isolates. Among the 230 clinical isolates included, Salmonella typhi was the most susceptible to cefoperazone, with 100% inhibition at MIC of ${\leq}0.5{\mu}g/ml$. Cefoperazone was also highly active against Streptococcus pyogenes(group A), Kletsiella pneumoniae, Staphylococcus aureus and Shigella flexneri, with 100% inhibition at $16{\mu}g/ml$ or less. More than 80% of Escherichia coli, Enterobacter aerogenes and Salmonella paratyphi was inhibited at ${\leq}16{\mu}/ml$, while Enterobacter cloaceae, Serratia marcescens and Pseudomonas aerogenosa were somewhat less sensitive to cefoperagone, with inhibitions of 60%, 55% and 35% respectively at the same MIC. 3) Animal pharmacokinetics Serum concentration, organ distritution and excretion of cefoperazone in rats were observed after single intramuscular injections at doses of 20 mg/kg and 50 mg/kg. The extent of protein binding to human plasma protein was also measured in vitro br equilibrium dialysis method. The mean Peak serum concentrations of $7.4{\mu}g/ml$ and $16.4{\mu}/ml$ were obtained at 30 min. after administration of cefoperazone at doses of 20 mg/kg and 50 mg/kg respectively. The tissue concentrations of cefoperazone measured at 30 and 60 min. were highest in kidney. And the concentrations of the drug in kidney, liver and small intestine were much higher than in blood. Urinary and fecal excretion over 24 hours after injetcion ranged form 12.5% to 15.0% in urine and from 19.6% to 25.0% in feces, indicating that the gastrointestinal system is more important than renal system for the excretion of cefoperazone. The extent of binding to human plasma protein measured by equilibrium dialysis was $76.3%{\sim}76.9%$, which was somewhat lower than the others utilizing centrifugal ultrafiltration method. 4) Animal pharmacodynamics Central nervous system : Effects of cefoperazone on the spontaneous movement and general behavioral patterns of rats, the pentobarbital sleeping time in mice and the body temperature in rabbits were observed. Single intraperitoneal injections at doses of $500{\sim}2,000mg/kg$ in rats did not affect the spontaneous movement ana the general behavioral patterns of the animal. Doses of $125{\sim}500mg/kg$ of cefoperazone injected intraperitonealy in mice neither increased nor decreased the pentobarbital-induced sleeping time. In rabbits the normal body temperature was maintained following the single intravenous injections of $125{\sim}2,000mg/kg$ dose. Respiratory and circulatory system: Respiration rate, blood pressure, heart rate and ECG of anesthetized rabbits were monitored for 3 hours following single intravenous inje

Al-xMg-CNT 복합분말체의 용융특성에 미치는 마그네슘 첨가와 온도의 영향

임정규 ( Jung Kyu Lim ),최경환 ( Kyong Hwan Choe ),김상섭 ( Sang Sub Kim ),조규섭 ( Gue Serb Cho ) 대한금속재료학회(구 대한금속학회) 2013 대한금속·재료학회지 Vol.51 No.4

We conducted melt-down experiments on Al-xMg-carbon nanotube (CNT) complex powder compacts at 700℃ and 800℃ for carrying the CNTs into the molten Al7021 matrix alloy. The parameters in the melting experiments were the holding temperatures and the amount of Mg content. The microstructures of the melt-down compacts were observed by optical microscopy (OM) and field emission scanning electro-microscopy (FESEM). The several phases obtained from the reaction products within the Al-xMg-CNT compacts were identified by energy dispersive X-ray spectroscopy (EDXS) and X-Ray diffractometry (XRD). The complete melt-down area was increased due to a large addition of Mg in the compacts and outer areas remained as undissolved powder compacts due to the large number of oxidation products such as MgO, MgAl2O4 and Al2O3. CNTs were observed on the surface of Al powders with oxidation products at 700℃ in a melting experiment. However, at 800℃, the CNT agglomerates moved away from the center because of the poor wettability and low density of the CNTs.

Intelligent Power Module의 플로팅 게이트 전원 공급을 위한 전하 펌프 회로의 설계

林廷圭(Jeong-Gyu Lim),鄭世敎(Se-Kyo Chung) 전력전자학회 2008 전력전자학회 논문지 Vol.13 No.2

입간측영(⽴竿測影)을 통해 만들어지는 각도기 기원에 관한 연구 - 선생님, 각도기는 어떻게 만들어졌나요? -

임정규,복기대 한국초등과학교육학회 2021 한국초등과학교육학회 학술대회 Vol.80 No.-

본 연구는 학생들이 “선생님 각도기는 어떻게 만들어졌나요? 왜 직각이 100°가 아니고 90°입니까?”라고 질문을 받았을 때 각도기 기원에 관한 자신 없는 답변에서 시작되었다. 현재 학계에서는 각도기의 기원에 관해서는 365일 지구의 공전에서 360° 각도기가 나왔다는 설과 바빌로니아의 60진법에서 유래되었다는 설 등이 있다. 본 연구자는 ‘각도기 180°는 자연계에서 만들어졌고, 태양의 일주운동 및 공전과 관계가 깊을 것으로 생각한다’. 본 연구에서는 고대인들이 “그림자 관측 즉, 입간측영을 통해 달력 및 해시계를 만드는 과정 속에서 각도기가 만들어졌다.”라는 가설을 실험을 통해 세우게 되었고, 직접 검증해 보았다. 각도기의 기원을 알아보기 위해 관측 실험과 천문 자료 수집을 통해 알아보았다. 넓은 대지에 기둥을 세우고 주변에 동지 남중 기준으로 원을 그리면 자연계에서 입간측영을 통해 각도기를 만들 수 있음을 알게 되었다. 또한, 미국 해양대기국 데이터 수집 분석을 통해, 각도기는 북반구 동절기(추분∼동지∼춘분) 180일 동안 아침, 저녁으로 태양의 일주운동 결과를 동지 기준으로 반원에 나타낸 것이 각도기라는 결과를 얻어낼 수 있었다. 북반구 동절기 자연계에서 만들어지는 각도기는 현재 쓰고 있는 각도기와 매우 흡사한 형태를 갖고 있다. 매일 매일 아침, 저녁으로 그림자의 위치가 하루에 약 1°(0.98∼1.02)씩 움직이므로 180칸으로 나누어짐을 다양한 통계를 통해 확인할 수 있었다. 관측 위치는 적도 인근에서 관측한 것으로 설계하였으나, 적도식으로 각도기를 적도면과 평행하게 세워 설계하면 지구 어디에서나 같은 값을 얻을 수 있음을 알 수 있었다. 본 연구를 통해 현재 사용 중인 180° 각도기와 유사한 각도기를 자연계에서 만들 수 있음을 입증해 내는 성과가 있었다고 생각한다. 현재의 360° 각도기는 입간측영 180° 각도기를 오랜 세월 동안 보완하여 오늘날의 360°에 이르렀을 것이라는 결론에 도달하게 되었다. 앞으로 현대 물리학과 천문학 전공자와 연계하여 각도기가 만들어진 과정을 보다 깊이 있게 토론하고 연구할 필요가 있다고 생각한다.

입간측영(立竿測影)을 통해 만들어지는 각도기 기원에 관한 연구

임정규 ( Jeonggyu Im ),복기대 ( Gidae Bok ) 사단법인 아시아문화학술원 2021 인문사회 21 Vol.12 No.5

본 연구의 목적은 수학, 과학, 천문학, 건축학 등에서 많이 활용되고 있는 각도기의 기원을 밝히는데 있다. 연구방법은 실험 및 가설검증이다. 주요 연구내용과 관련하여 각도는 태양의 일주운동 및 공전과 관계가 깊다는 주장을 실험 및 자료 수집을 통해 알아보았다. ‘고대인들의 그림자 관측 즉, 입간측영을 통해 달력 및 해시계를 만드는 과정 속에서 각도가 만들어졌다’라는 가설을 가설검증을 통해 알아보았다. 또한, 각도에서 사용되는 1°, 180°가 자연계에서 만들어지는 사례를 미국 해양대기국의 프로그램을 활용하여 수집 분석하였다. 그 결과, 넓은 판에 기둥을 세우고 주변에 동지 때 남중고도 기준으로 원을 그리면 자연계에서 입간측영을 통해 1° 즉 각도를 만들 수 있음을 알게 되었다. 또한, 자료 수집 분석을 통해, 매일 아침, 저녁으로 그림자선의 위치가 하루에 약 1°씩 움직임이고 180칸으로 나누어짐을 통계를 통해 확인할 수 있었다. 입간측영을 통해 180° 각도기와 유사한 각도기를 자연계에서 만들 수 있음을 입증해 내는 성과가 있었다. The purpose of this study is to reveal the origin of the protractor, which is widely used in mathematics, science, astronomy, and architecture. Research methods are experimentation and hypothesis verification. The claim that the angle is deeply related to the sun’s diurnal motion and orbit was investigated through experiments and data collection. The hypothesis that ‘angles were created in the process of making calendars and sundials through the ancient people’s observation of shadows, that is, interrogation’, was investigated through hypothesis verification. Cases in which 1°, 180° used in angles are made in the natural world were collected and analyzed using the program. As a result, it was found that by building a pillar on a wide plate and drawing a circle around the solstice at the solstice, it is possible to create an angle of 1° through inter-incline measurement in the natural world. Through data collection and analysis, it was possible to confirm through statistics that the position of the shadow line moves about 1° per day and is divided into 180 spaces every morning and evening. There was a result of proving that a protractor similar to a 180° protractor can be made in the natural world through standing pole shadow measurement.

Intelligent Power Module의 플로팅 게이트 전원 공급을 위한 전하 펌프 회로의 설계

임정규(Jeong-Gyu Lim),김석환(Seok-Hwan Kim),서은경(Eun-kyung Seo),정세교(Se-Kyo Chung) 전력전자학회 2005 전력전자학술대회 논문집 Vol.- No.-

A bootstrap circuit for floating power supply has the advantage of being simple and inexpensive. However, the duty cycle and on-time are limited by the requirement to refresh the charge in the bootstrap capacitor. Hence, this paper deals with a design of charge pump circuit for a floating gate power supply of an IPM. The operation of the proposed circuit applied by three-phase inverter system for driving induction motor are verified through the experiments.