용매의 선택에 따른 전도성 Polyaniline의 자기적 성질변화

오응주,서정선,노태호,류광선,정상국,송승기 명지대학교 자연과학연구소 1994 자연과학논문집 Vol.11 No.-

Polyaniline(emeraldine base:EB)를 pH에 따라 HCI로 1차 doping을 한후ESR을 사용하여 자기적 성질을 조사했다.또한 emeraldine base를 camphorsulfonic acid(HCSA), dodecylbenzene sulfonic acid(HDBSA)등의 산으로 1차 doping 시키고 이것을 m-cresol, acetic acid, 및 formic acid에 녹여 2차 doping을 한 후 SQUID 를 이용하여 자기적 성질을 측정하였다. Doping에 사용된 HCI용액의pH가 감소함에 따라 ESR 신호의 강도가 증가하였으며, 이로부터 doping에 따라 상자성을 나타나게 하는 화학종이 가타다는 것을아타내고 있다.m-cresol내에서 HCSA 및 HDBSA로 각각 doping된 EB-CSA/m-cresol 과 EB-DBSA/m-cresol 시료 무두 상자성을 나타내었고, 온도가 증가함에 따라 자하율값이 감소하는 경향을 나타내었다.χ?값은 2.18x10?과 7.87x10?emu/mol2-rings unit 보이며 두 스핀에 대한 Fermi 에너지 level(E?)에서의 상태밀도를 나타내는 N(E?)는 0.67과 0.24 상태(eV/2-rings unit?)로 나타났다.Camphorsulfonic ascid(HCSA)로 doping 된 EB를 m-cresol, acetic acid 및 chloroform 등 다른 용매에서 처리시 관찰된 자화율의 변화를 온도에 의존하지 않는 χ?값과 온도에 의존하는 χ? 값으로 구분하여 curie spin의 온도의존성을 규명하였다. Dependency of magnetic properties of polyaniline(emeraldine base:EB)on the pH of HCI used in doping was inverstigated by electron spin resonance spectroscopy. Emeraldine base doped with functionalized acid (primary dopant) such as camphorsulfonic acid (HCSA), dodecylbenzene sulfonic acid(HDBSA) was processed in various solvents (m-cresol, acetic acid, formic acid etc.)into homogeneous solution and free standing film and its magnetic properties were measured by SQUID. The intensity of ESR signal was increased with decrese in pH of HCL solution and paramagnetic behavior of doped polyaniline due to the formation of polaron upon doping could be confoirmed from these results. The same g value of 2.004±0.001 measured for all of the samples means that the chemical species which show paramagnetism are sasme. Polyanilines doped with HCSA and HDBSA in m-cresol showed paramagnetism and decrease in susceptibility with increase in temperature. χ? value was appered 2.18x10? and 7.87x10? emu/mol2-rings unit and N(E?) which is density of states at Fermi energy level for two spins was 0.67 and 0.24 state eV? 2rings unit? respectively. The changes in susceptibility of polyanilines doped with HCSA in m-cresol, acetic acid, formic acid etc. were divided into temperature independent χ? term and temperature dependent χ? term and temperature dependency of curie spin concentration was examined.

뇌실내출혈로 인한 급성 수두증에서 관찰된 해리증후군

김광기,이경민,이정주,오종배,안태범,정상욱,남현우,박성호 대한신경과학회 1999 대한신경과학회지 Vol.17 No.5

수은폭로 근로자의 조기 신기능 장해 지표로서의 요중 β-Galactosidase 활성도에 관한 연구

오연희,김광종,천병철,박종태 大韓産業醫學會 1995 대한직업환경의학회지 Vol.7 No.1

The objective of this study was to evaluate the relationship between β-galactosidase activity in urine, in serum and urinary N-acetyl-β-glucosaminidase activity as an early indicator of renal effect and mercury concentration in urine and blood, reflecting the intensity of exposure to or the amount of body burden of mercury. This study was carried out among 70 workers exposed to mercury vapor and 63 non-exposed workers as a reference. The results were as follows; 1. The mean concentration of urinary mercury(43.5 ㎍/l) in exposed subjects was about nine times higher than that of non-exposed subjects, but the mean values of blood mercury were not different from each other. 2. The mean values of β-galactosidase activity in urine(119.7μmolMU/h/g creatinine) and in blood(73.7 molMU/h/l) of mercury-exposed subjects were significantly higher than those of non-exposed subjects. 3. In mercury-exposed subjects, β-galactosidase activities in urine(r=0.38, P<0.01) and in serum(r=0.26, P<0.05) were correlated to urinary mercury concentration, but not to blood mercury concentration. The urinary excretion of β-galactosidase activity was closely associated with urinary mercury concentration in the result of the multiple regression analysis. 4. The urinary β-galactosidase activity in exposed subjects increased as the urinary mercury increased, and in the exposed subjects with more than 50㎍/l of urinary mercury was highly related to urinary β-galactosidase activity(r=0.47, P<0.05). 5. Among exposed subjects with more than 50㎍/l of urinary mercury, 20.0% of them showed abnormal value of urinary β-galactosidase activity.

MnO₂를 촉매로 사용한 SnO₂계 CO센서의 특성

오태영,한상도,이상호,명광식,박기배 경북대학교 센서기술연구소 1998 센서技術學術大會論文集 Vol.9 No.1

CO sensors were fabricated with SnO_(2) thick-films using MnO_(2) or V_(2)O_(5) catalysts. The SnO_(2) thick-films doped with MnO_(2) or V_(2)O_(5) showed better selectivities to CH_(4), NO_(x) than the pure SnO_(2) film material in air at operating temperature of 450°C, 500°C respectively. In addition, MS2-2[(3wt%)MnO_(2)+SnO_(2)] showed better selectivity than SVS[(3wt%)V_(2)O_(5)+Pd+SnO_(2)]. MS2-3[(6wt%)MnO_(2)+SnO_(2)] showed the highest selectivity for 420ppm-NO_(x), 3500ppm-CH_(4) at 450°C

이동 애드 혹 네트워크에서 QoS를 지원하는 AODV 라우팅 프로토콜

吳世德,趙榮泰,丁燦赫,金玄郁,李光培,姜景仁,朴京培,文泰洙,郭承郁,河載承 明知大學校 産業技術硏究所 2003 産業技術硏究所論文集 Vol.22 No.-

Abstract - In this paper, we propose a bidirectional mobile Ad Hoc routing protocol based on AODV(ad-hoc on-demand distance victor routing) with QoS(quality of service) support. At presence, wireless mobile communication focuses on how to efficiently support mobility of users more than QoS guarantee. However, in order to satisfy requirement of various applications which have been or will be served, QoS guarantee between end point is a very important issue. The existing AODV routing protocol is implemented to use only BE (Best Effort) service. However, actual wireless mobile environment requires to reduce a waste of communication resources and meet with the real-time change of data paths by setting up routes with QoS support, considering available communication resources at each node in advance. Therefore, in this thesis, we propose an adaptive QoS support method using hello message in order to rapidly meet with the change of available communication resources and to smoothly perform route maintenance. For performance evaluation, we analyzed the average date reception rate. At that time, we used evaluation parameters such as node's mobility -stop time, hello message period, and packet priority, considering the node's mobility and the number of best effort/QoS data flows. As results, we found that with our proposed method the average data reception rate was increased 16.3% for 0 mobility-stop second case and 4.7% for 300 mobility-stop second case.

비전도성 접착제를 이용한 COG 본딩용 Sn/Ag 범프에서 본딩 응력이 접속저항에 미치는 영향

이광용,이윤희,김영호,오태성 대한금속재료학회 2005 대한금속·재료학회지 Vol.43 No.3

Chip-on-glass bonding using nonconductive adhesive was accomplished with joining of the Sn/Ag bumps, and the average contact resistance of the Sn/Ag bump was measured with variation of the bonding stress. Average contact resistance of the Sn/Ag bump could be obtained from the slope of the curve for daisy chain resistance vs. number of Sn/Ag bumps. With increasing the bonding stress from 31.8 MPa to 69.8 MPa, the average contact resistance decreased from 30 mil/bump to 15.6 mΩ/bump. With further increasing the bonding stress above 69.8 MPa, however, the average contact resistance changed little within the range of 12.9-15.6 mil/bump. Among the factors affecting the contact resistance with variation of the bonding stress, plastic deformation of the Sn/Ag bump had larger effect than the amount of the microvoids remaining at the contact interface between Sn/Ag bumps. (Received November 22, 2004)

소아 상완골 과상부 골절에 대한 임상적 고찰

이광진,박건영,오선태 충남대학교 의과대학 지역사회의학연구소 1991 충남의대잡지 Vol.18 No.2

In the pediatric age group, the supracondylar fracture of humerus is the second most common fracture after that of the forearm. But the supracondylar fracture of humerus in children has a greater rate of rereduction, nerve injury, surgical intervention, and poor results than any other type of extremity fracture. Forty eight cases of 48 children with the supracondylar fracture of humerus who had been treated at the department of orthopaedic surgery, Chungnam National University Hospital from February, 1986 to January, 1991, were analyzed retrospectively for the methods of treatment and its results. 1. The mean age of the patients was 8.3 years, ranging from one to fourteen years. 26 boys and 22 girls with minimum six months follow-up were included in this sudy and the most of the causes of injuries were silp-down(45.8%) and fall-down from height(50.0%). 2. Of all fractures, the extension type was 46 cases(95.8%) and the flexion type was 2 cases(4.2%). 3. Accoding to the classification by Pirone et al., fractures were classificated to type Ⅰ in 2 cases, type Ⅱ-A in 6, type Ⅱ-B in 14 and type Ⅲ in 26 cases. 4. There were 8 cases of concomitant peripheral nerve injuries, radial nerve palsy in 6, ulnar nerve in 1 and median nerve in 1 case. 5. The treatment were consisted of closed reduction and casting in 10, closed reduction and percutaneous pinning in 20, and open reduction and multiple pinning in 18 cases with or without preoperative skeletal traction. 6. The clinical and radiological results were Excellent in 22(45.8%), Good in 13(27.1%), Fair in 8(16.7%) and Poor in 5(10.8%) cases, according to the criteria of Flynn. 7. The closed reduction and percutaneous pinnings of 20 cases were rated Excellent and Good results in 18(90.0%) cases and these results were superior to another methods of treatment. So we concluded that the closed reduction and percutaneous pinnings was simple, safe and effective method of the treatment for the supracondylar fracture of the humerus in children. But it was technically difficult to reduce the displaced fracture satisfactory by closed manipulation and in these cases, the open reduction was still indicated.

식이 상태와 카페인 투여가 일회적 운동 시 흰쥐 가자미근의 제 4형 당수송체에 미치는 영향

김광찬,김종오,오명진,윤재석,서태범,윤진환,정일규 한국스포츠리서치 2004 한국 스포츠 리서치 Vol.15 No.6

The purpose of this study was to evaluate the effects of diet condition and caffeine ingestion prior to long distance treadmill running on the GLUT-4 protein expression in Sprague-Dawley rats' soleus muscle. Total is rats were used For subjects and assigned to six groups: Fasting control(FaC group), feeding control(FeC), asting+exercise(FaE), feeding +exercise(FeE), Fasting +caffeine+exercise(FaCE), and Feeding+caffeine+exercise(FeCE). Each animal belongs to fasting group was forced to be in fasting state at least for 14 hours, The food was provided to each rat in feeding group 12minutes prior to treadmill running and the caffeine was ingested through the stainless steel tube 60minutes prior to exercise. All rats in exercise groups were forced to perform treadmill running for B9 minutes at the speed of 18m/min, and 0%grade, immediately after exercise, all animal was anesthetized by Chlorofolm (DC Chemical, Co, Ltd) and about 10ml of blood was drawn from each animal's heart and than soleus muscle was exposed and separated from the rat's leg. we found that the GLUT-4 in feeding groups increased much significantly compared to fasting groups(p<.05). The exercise in fasting state appeared to suppress the expression of GLUT-4 protein different from the exercise in feeding state. Cafreine ingestion prior to treadmill running of 60 minutes induced the significant increase or GLUT-4 protein expression both in fasting or feeding states.

제1형 당뇨병 환자에서 췌도세포 동종이식의 반복시행

양태영,정인경,서인아,오은영,조건영,오승훈,김성주,정재훈,민용기,이명식,이문규,김광원,도영수,주성욱 대한당뇨병학회 2002 Diabetes and Metabolism Journal Vol.24 No.4

연구배경:췌도세포 이식은 시술이 간편하고 안전하기 때문에 반복이식이 가능하여 그 동안 여러 센터에서 반복이식의 성공을 보고한 바 있다. 국내에서도 본 병원을 비롯하여 몇몇 센터에서 췌도세포 이식이 활발히 시도되고 있으나 사람에서의 동종이식 및 동종 이식의 반복시행은 보고된 바 없는 실정이다. 저자 등은 국내 최초로 췌도세포 동종이식을 시행하여, 혈청 C­펩타이드가 증가하고 인슐린 요구량이 감소하였으며, 혈당농도와 당화혈색소의 안정을 보였다. 그러나 이식 70일 후 다시 인슐린 요구량이 증가하고 C­펩타이드가 감소하여 췌도세포 이식을 다시 시행한 바 있다. 2차 이식 후 70여일이 지난 현재 다시 혈청 C­펩타이드가 증가하고, 인슐린 요구량이 더 감소되어 췌도세포 이식에서 반복 시행의 유용성을 보고하는 바이다. 방법:환자는 32세 남자로 17년전 당뇨병 진단 후 인슐린 치료 중이었으며, 3년전 부터는 만성신부전증으로 혈액툭석을 하고있었다. 1999년 12월 25일 신장이식을 하였고 3일 후 췌도이식을 하였으며, 두번째 이식은 70일 후 시행하였다. 췌도분리는 변형된 Recordi방법과 비연속성 자당 농도차(discontinuous density gradient)를 이용하였으며 분리한 췌도는 배양 후 환자의 신장기능이 정상화되고 미생물학 검사에서 음성을 확인한 후 경피경간으로 간문맥을 접근하여 16G 폴리 에틸렌 카테터를 이용하여 간실질에 이식하였다. 결과:1차 췌도이식시 순수분리전 췌도수는 210,000개, 순수분리후 획득한 췌도수는 90,000개, 순도 95%, 세포양 1.0mL 이었고, 2차 췌도이식시 순수분리전 췌도수는 420,000개, 순수분리후 획득한 췌도수는 370,000개, 순도 95%, 세포양 1.5mL 이었다. 1,2차 모두 간문맥을 통해 약 20분에 걸쳐 간실질에 주입하였다. 췌도이식전 인슐린요구량은 75∼75U/일, HbA1e 8∼10%, C­펩타이드 0.6ng/mL 였으며, 1차 췌도이식수 7일째 인슐린 요구량은 40U/일, C­펩타이드 1.5ng/mL, FPS 109mg/mL 였고, 40일 추적관찰 후 인슐린 요구량이 36U/일, C­펩타이드 1.8ng/mL, HbA1e 6.5∼7.0%로 안정되었다. 그러나 이식 50일째부터 인슐린 요구량이 50∼56U/일, C­펩타이드 0.6ng/mL, FPS 130∼200mg/dL로 혈당 조절이 불안정하여 다시 췌도이식을 시행하였다. 2차 이식후 50일이 경과한 현재, 인슐린 요구량은 26U/일, C­펩타이드 1.8ng/mL, FPS 90∼120mg/dL로 다시 안정되었다. 결론:췌도이식은 반복이식이 가능하며, 본 환자의 경우 인슐린요구량 감소, 혈당의 안정화 및 C­펩타이드가 상승하여 이식한 췌도의 기능을 확인할 수 있었고, 향후 스테로이드 등 면역억제가 유지 용량으로 감량되면 인슐린 요구량은 더 감소될 것으로 기대된다. Over the past 20 years, significant advances have been made in human islet transplantation. However, cases of prolonged insulin independence after islet allotransplantation have rarely been reported and over time, a slight, gradual decrease in insulin secretion appears to occur, as suggested by the lower C-peptide. Although preliminary clinical success achieved over the past few years has been considerably higher with whole pancreatic transplant than with isolated islet grafts, both approaches remain experimental. Islet grafts might gain, over time, increasing credibility and might eventually provide an easier alternative in terms of grafting procedures and patient management, as compared with the more "traumatizing" whole-pancreas transplantation. Also, using islet, re-transplantation is possible. But it is not known whether re-transplantation of islet could be suitable for those patients who lost grafted islet function. The aim of the present study was to investigate the benefits of re-transplantation of islet in previously simultaneous islets-kidney transplant (SIK) patient who have lost graft function. Methods : The recipient was a 32 year old male. First islet transplantation was underwent at December 25, 1999. However, the grafted islets lost function after 70 days. So we performed re-transplantation of islets. The isolation of islet was conducted sterilely on a laminarflow hood and isolated by a modified Recordimethod. The islet was injected slowly into the liver via a cannular placed in the potalvein for 20 minutes. Results : Transplanted islets were 90,000 IEq at first islet transplantation, 370,000 IEq at second islet transplantation. The insulin requirement was reduced from 75-85 to 35-40 U/day, the basal C-peptide level was 1.5 ng/mL at 7 days posttransplant Unfortunately, the grafted islets lost function after 70 days. After second transplantation, the insulin requirement was reduced to 26 U/day. Conclusions : Despite the continuous need for exogenous insulin therapy, islet transplantation can prevent wide glucose fluctuations, thus resulting in normalization of glycemic control and improvement in HbAlc, and also, show that islets can be successfully and safely re-transplanted intraportally in patients who have lost previously grafted islet function (J Kor Diabetes Asso 457~466, 2000).

HDPE 개질 아스팔트 혼합물의 강도 및 변형특성

김광우,이기호,권오선,고태영 강원대학교 부설 석재복합신소재 제품연구센터 2004 석재연 논문집 Vol.9 No.-

본 연구는 폐비닐 펠렛을 도로포장재료로 재활용하여 자원절약 및 아스팔트 혼합물의 품질향상을 위한 연구이다. 이를 위하여 폐비닐의 첨가량별 배합설계를 수행하여 적정 폐비닐 첨가량과 최적 아스팔트 함량으로 편마암과 화강암 2가지 골재와 폐비닐인 RHDPE의 함량을 4가지로 혼합물을 제작하여 8종류의 재질 혼합물과 2종류의 무개질 혼합물을 제작하였다. 그리고 이 공시체에 대하여 마샬안정도, 간접인장강도 및 Kim test와 반복주행시험 등 실내시험을 통하여 혼합물의 특성을 분석하였다. 폐비닐 첨가량은 RHDPE가 8%일 때 안정도와 간접인장강도 모두 가장 우수한 것으로 나타났고 취성도 나타나지 않았다. RHDPE를 첨가한 혼합물에 대하여 Kim test를 수행한 결과 DR과 DS 모두 높은 상관성을 보였다. 그리고 반복주행시험에서는 RHDPE를 첨가한 혼합물이 일반 혼합물보다 우수하였다. 향후 많은 실험을 통해 RHDPE의 우수성을 입증한다면 소성변형 저항성에 우수한 재료로 이용될 수 있을 것이다. This study is a fundamental research for recycled high-density polyethylene (RHDPE) in asphalt mixture for improving roadway pavement. Marshall mix design was conducted and optimum asphalt content(OAC) was determined for dense-graded surface course mixture by RHDPE content. Marshall stability test, indirect tensile strength (ITS) test, wheel tracking trest and Kim-test were carried out to measure the characteristics of RHDPE-added asphalt concretes. From the results of this study, RHDPE in asphalt mixture if possible. It could be considered that adding too much RHDPE in asphalt mixture is not proper. The optimum content of RHDPE was appeared to be 8%. In Kim-test, statistical analysis was performed for each loading head and aggregate to find out correlation between S_(D) values and each rut parameter. The analysis result showed that S_(D) had very high coefficient of determination with rut parameters on the average.