" The Korean Journal of Chemical Engineering " 게재 논문 요약 : Processabilities & Mechanical Properties of the Biodegradable LDPE / Modified Starch Blends

Young Jin Kim,Yong Man Lee,Hyang Mok Lee,O Ok Park 한국화학공학회 1994 NICE Vol.12 No.5

N/A An investigation of the biodegradable polymers based on starch has been accomplished. Starch needs to be modified before blending with low density polyethylene(LDPE) because of its hydrophilicity. Three kinds of modification methods were applied to obtain the compatibility to starch-LDPE blends. The first one was the esterification of the hydroxyl group of starch with acetic anhydride. The second was the copolymerization of actylonitrile and styrene onto starch. The last was the esterification reaction of the hydroxyl group of starch with three kinds of ionomers. The tensile strength, % elongation, Young`s modulus, and shear viscosities of blends of the modified starch and LDPE were examined. Ionomer-treated starch showed better compatibility with LDPE to give better performances than other blends.

Rat의 복강내에 투여한 5-fluorouracil-polyglycolic acid 제형이 장기에 미치는 영향에 관한 연구

강대영,송규상,최정목,노승무,정경수,오정연,김진향,양준묵,최선웅,이진호,조준식,민병무,김용백,김창식,박근성,김승영,김학용,인현빈 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

For more effective intraperitoneal chemotherapy, the authers made 5-fluorouracil-polyglycolic acid composite disks(FU-PGA disks) with 5-fluorouracil and polyglycolic acid, a biodegradable polymer. We inserted the FU-PGA disk into the peritoneal cavites of Sprague-Dawley male rats, the control and three experimental groups; one FU-PGA disk insert group(300mg/kg), two FU-PGA disk insert group(600mg/kg), and three FU-PGA disk insert group(900mg/kg). The control group received a similar number of PGA disk inserts. A pharmacokinetic study was performed to measure the 5-fluorouracil concentration in the peritoneal fluid, blood, and tissues(liver, kidney and heart) at 24 hours, 72hours and 168 hours after insertion of the FU-PGA disk. Light and electron microscopic studies were done. The results were as follows: 1) The number of white blood cells and platelets decreased after FU-PGA insertion. The degree was proportional to the duration and amounts inserted. The change in the number of red blood cells varied slightly. 2) Light microscopically, slight changes were noted at 168 hours in the 3 disk insert group (900mg/kg). Mild fatty change and hepatocyte degeneration around the central veins of the liver were noted, with vacuolar degeneration in the proximal convoluted tubules of the kidney. 3) Electron microscopically,the liver showed focal increases of lipid droplets in the hepatocytes, and irregular nuclear membrane with focal nucleolar segregation of the fibrillar and granular elements. Also the double membranous structure of the hepatocytes and Kupffer cells was widened with bleb formation. The kidney showed wide separation of the nuclear double membrane in the proximal convoluted tubular cells and mesangial cells, with vacuolation and myelin figure formation in the mitochondria of the proximal convoluted tubular cells, at 72 hours and 168 hours in the 2 to 3 FU-PGA insert groups. The heart showed focal loss of cristae,vacuolation and myelin figure formation in the mitochondria of the 2 to 3 FU-PGA insert groups. In conclusion, despite the large amont of FU-PGA inserted, the histopathological changes in the liver, kidney and heart were slight, and consonant with the very low amount of 5-fluorouracil concentrations detected in the liver, kidney and heart. The above results suggest that the FU-PGA composite can serve as a new device for releasing drugs in a controlled manner and easily targeted to intraperitoneal organs. This device can improve the efficacy of intraperitoneal chemotherapy for gastric cancer.

PROCESSABILITIES & MECHANICAL PROPERTIES OF THE BIODEGRADABLE LDPE/MODIFIED STARCH BLENDS

Kim, Young Jin,Lee, Yong Man,Lee, Hyang Mok,Park, O Ok 한국화학공학회 1994 Korean Journal of Chemical Engineering Vol.11 No.3

An investigation of the biodegradable polymers based on starch has been accomplished. Starch needs to be modified before blending with low density polyethylene (LDPE) because of its hydrophilicity. Three kinds of modification methods were applied to obtain the compatibility to starch-LDPE blends. The first one was the esterification of the hydroxyl group of starch with acetic anhydride. The second was the copolymerization of acrylonitrile and styrene onto starch. The last was the esterification reaction of the hydroxyl group of starch with three kinds of ionomers. The tensile strength, % elongation, Young's modulus, and shear viscosities of blends of the modified starch and LDPE were examined. Ionomer-treated starch showed better compatibility with LDPE to give better performances than other blends.

백서의 복강내에 투여한 Mitomycin-C-Polyglycolic acid 제형이 장기에 미치는 영향에 관한 연구

송규상,강대영,최정목,노승무,정경수,오정연,김진향,양준목,최선웅,이진호,조준식,민병무,김용백,김창식,박근성,김승영,김학용,인현빈 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

To evaluate the in-vivo effects of mitomycin-C-polyglycolic acid composite(MMC-PGA) the disk: shaped composite were implanted into the peritoneal cavity of the Sprague-Dawley rats. The pathologic changes were examined at various time points up to 12 weeks. Initially the soft tissue around the inserted disks showed capillary congestion at 3 days. Inflammatory infiltrates with foreign body giant cells appeared from the 2nd week and reached peak response at 6-8 weeks. These reaction diminished prominently at 12 weeks. No specific pathologic change was found in the liver, the kidneys, and the heart. The above results suggest that the MMC-PGA composite can serve as a new device for intraperitoneal chemotherapy of various types of cancers.

이산화질소, 암모니아 및 수분의 기상반응에 의한 암모늄염 생성 거동에 관한 연구

목영선,이호원,현영진 제주대학교 해양과환경연구소 2001 해양과환경연구소 연구논문집 Vol.25 No.-

This study investigates the kinetics of the gas phase reaction between nitrogen dioxide, ammonia and water vapor, and presents the appropriate ranges of the process variables such as initial NO_2 concentration, absolute humidity and reaction temperature for the effective removal of nitrogen dioxide. According to the kinetic calculations, the gas phase reaction for the removal of NO_2 takes effectively place at the water vapor content higher than 4-6 %(v/v), but further increase in the water vapor content does not significantly enhance the removal. The residence time required to achieve a desired removal efficiency of NO_2 was found to increase with the decrease in its initial concentration. Especially, the residence time required rapidly increases when the initial concentration of NO_2 is less than 100 ppm. The removal rate of NO_2 is in inverse proportion to the reaction temperature, i.e., lower temperature is favorable to promote the removal rate. The results obtained in this study may be useful for the determination of the optimal values of the process variables in non-thermal plasma technology for the removal of nitrogen oxides.

유전체 플라즈마 방전을 이용한 톨루엔 분해 공정에서 충진물,인가 전압,가스 조성 및 전압 극성이 분해효율 및 전력 전달에 미치는 영향

목영선,이호원,현영진,함성원,조무현,남인식 한국화학공학회 2002 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.40 No.1

교류 고전압을 이용하는 유전체 플라즈마 반응기에서 휘발성유기화합물의 일종인 톨루엔의 분해에 대한 연구가 수행되었다. 유전체 충진물로는 직경 4-6㎜인 유리구슬과 4.75-6.7㎜인 천연 제올라이트가 사용되었다. 톨루엔의 분해 및 전력공급에 미치는 유전체의 물리적 특성, 산소함량, 피크전압, 전압 극성의 영향에 대해 고찰하였다. 유리구슬과 천연 제올라이트가 유전체 반응기에 충진되었을 때, 톨루엔의 분해 성능 및 방전 전력이 증가되었다. 천연 제올라이트는 높은 비표면적에도 불구하고, 톨루엔 분해성능 및 전력공급에 있어서 유리구슬과 유사한 특성을 보여 주었는데, 이러한 결과는 정상상태에서 유전체의 흡착성이 톨루엔의 분해에 영향을 주지 못하며, 톨루엔의 분해는 플라즈마 방전에 의해서만 활성화된다는 것을 의미한다. 유전체 충진물이 없을 때는 유전체 충진물이 있을 때 보다 매우 높은 전압에서 톨루엔의 분해가 일어나기 시작하였다. 산소 함량이 증가될수록 톨루엔의 분해 효율이 조금씩 증가하였는데, 이 결과는 산소에서 비롯된 활성 성분인 O 라디칼, O^+ 및 O_2^+이온 등이 질소에서 비롯된 활성 성분(N, N^+, N_2^+)보다 톨루엔의 분해에 있어서 더 중요한 역할을 한다는 것을 나타낸다. 교류 고전압을 반파 정류하여 양 또는 음의 고전압만을 반응기에 인가하였을 때는 방전전력 및 톨루엔 분해효율이 교류의 경우보다 크게 감소하였다. 양의 고전압과 음의 고전압은 톨루엔 분해 및 전력공급에 있어서 동일한 특성을 나타내었다. 고온 소각 및 유전체 플라즈마 공정에서 얻어진 톨루엔 분해반응 속도를 서로 비교한 결과, 고온 소각이 더 높은 분해반응속도를 가지는 것으로 나타났으나, 고온 소각을 위해서는 상당량의 열에너지가 필요하므로 유전체 플라즈마 공정이 충분히 경쟁 가능한 기술임을 알 수 있었다. Dielectric barrier plasma reactor using AC power was applied to the decomposition of toluene. Natural zeolite of 4.75-6.7㎜ and glass beads of 4 to 6㎜ in diameter were used as the dielectric packing materials. The effects of the dielectric packing materials, the oxygen content, the peak voltage, the voltage polarity on the decomposition of toluene and the power delivery were examined. When the dielectric materials such as glass beads and natural zeolite were packed in the reactor, the performance for the decomposition of toluene and the discharge power increased. Despite the adsorption capability, the zeolite showed similar decomposition performance to the glass beads, which indicates that the adsorption capability does not affect the decomposition of toluene in steady state condition. In the absence of the dielectric packing material, higher voltage was required to decompose toluene. As the oxygen content was increased, the decomposition efficiency slightly increased. When the AC voltage was rectified to positive or negative half-wave, the discharge power and the decomposition efficiency greatly decreased. The decomposition efficiency of toluene was identical, regardless of the voltage polarity changed by half-wave rectification. Although the thermal incineration has larger decomposition rate constant than the dielectric barrier plasma processit requires a lot of thermal energy to heat the gas to a high temperature, and thus the dielectric barrier plasma process is considered to be sufficiently competitive to the thermal incineration.

후두와 병변 수술의 발생한 경막하 긴장성 기두증

목진호,김한식,이규춘,박용석,이영배 東國大學校醫學硏究所 1999 東國醫學 Vol.6 No.-

긴장성 기두증은 신경외과영역에서 개두수술 후에 발생할 수 있는 드문 합병증으로 특히 만성 뇌경막하 혈종 제거수술이나 좌위에서 후두와 수술을 시행한 경우에 발생할 수 있다. 따라서 개두수술 후에 신경학적 증상의 악화가 있거나 수술 후 예상경과를 취하지 않는 경우에는 긴장성 기두증의 발생 가증성을 항상 고려하여야 한다. 긴장성 기두증의 발생기전은 물병을 거꾸로 세운 것과 같은 기전(Inverted pop-bottle mechanism)으로 뇌척수액이 누수된 만큼 공기방울이 경막하강으로 올라가 빈 공간을 메우는 것이다. 이와 같은 기전으로 두개강내로 들어간 공기가 일정한 압력을 가지게 되어 주변 뇌조직을 압박하여 신경학적 장애를 초래하게 된다. 뇌전산화 단층촬영을 이용하여 쉽게 진단이 가능하며 치료는 두개골 천공을 시행하여 두개강내 공기를 배기시켜 줌으로서 가능하다. 저자들은 복와위에서 후두와 병변 수술 후에 발생한 긴장성 기두증을 뇌전산화 단층촬영을 이용하여 진단하고 전두골을 천공하여 두개강내 공기를 배기시켜 치험하였기에 문헌고찰과 함께 증례를 보고하는 바이다. 중심단어:긴장성 기두증, 후두와 수술, 경막하강, 복와위 Tension pneumocephalus is a rare complication in neurosurgical operation and should be considered whenever a patient fails to recover as expected following surgery. The possible mechanism for the entry of air into the subdural space is analogous to the entry of air into an inverted soda-pop bottle. As the fluid pours out. air bubbles reach the top of the container, Computed tomography permitted rapid diagnosis including localization of the air, thus facilitating prompt treatment. Peaking of frontal lobe. mountain appearance of frontal lobe. and air densities at the cisterns are characteristic findings of' tension pneumocephalus on brain CT scan. This condition is easily diagnosed and treated using twist-drill aspiration. The authors describe a case of subdural tension pneumocephalus complicating the early postoperative course after posterior fossa surgery in the prone position.

저온 플라즈마를 이용한 휘발성 유기화합물의 분해에 관한 연구

목영선,이호원,현영진 제주대학교 환경연구소 2000 환경연구논문집 : 제주대 Vol.8 No.-

A non-thermal plasma process using pulsed corona discharge was applied to the destruction of a volatile organic compound (propene). Propene was found to be easily destroyed by this process, and the destruction efficiency was proportional to the supplied power while it was in inverse proportion to the initial propene concentration. Ethane and formaldehyde were detected at the reactor outlet, but the concentrations of such byproducts were negligible. The destruction rate equation (first order in terms of propene concentration) and the rate constant (6.75×10^(3)s^(1)W^(1)) proposed were validated by the comparison between the calculations and experimental data. The increases in the contents of oxygen and water vapor decreased the pulse energy delivered to the plasma reactor. At the initial concentration of 5.85 X 10^(3) mol/㎥, the average energy requirement to destroy one molecule of propene was in the range of 26 to 47 eV according to the amount of propene destroyed, which is relatively low value, compared with that of nitric oxide(NO).

두부외상후 생존기간에 영향을 주는 요인분석

목직호,김한식,이규춘,이영배 동국대학교 경주대학 1997 東國論集 Vol.16 No.2

1995년 7월부터 1997년 7월까지 최근 2년간 본원 신경외과에 입원한 343례의 두부손상 환자중 사망한 25례를 조기사망군(7일이내)과 후기사망군(7일후)으로 분류하여 분석해본 결과 7.3%의 사망률을 보였으며 남자 사망자는 여자에 비해 3.2배였으며, 연령 별로는 조기사망군은 40대이상에서 많았고 후기 사망군은 60대 이상의 고령에서 다소 많았다. 조기사망군에서는 낮은 GCS, 비정상적인 동공반사 반응, 타장기 손상, 저혈압, 저산소증, 고혈당, 심한 정중전이, 뇌실압박, 두개골 골절, 개두술의 빈도가 높게 조사되었다. 이송시간은 조기사망군에서 1시간 이내에 도착한 경우가 많아 신속한 후송이 이루어졌다. 한편 후기사망군에서는 저이산화탄소혈증, 빈혈, 고나트륨혈증등이 높게 조사되었다. 사인은 조기사망군에서 1차성두개강내 병변 및 저혈량 등이 많았고 후기사망례는 폐렴, 성인성 호흡곤란 증후군, 외상후성 뇌경색증 등이 주요 사망 원인이었다. 따라서 생존기간별로 위험도가 높은 요소를 찾아 그에 대한 적극적인 치료를 하는 것이 두부 손상으로 인한 사망률을 개선하는데 바람직한 것으로 생각된다. We present a study the variable factor in the early(within one week) and late death(after one week) after head injury. The multiple factors were analysed on the clinical, imaging, and laboratory characteristics of 25 patients who were dead among 343 head injured persons during recent 2 years form July, 1995 to July, 1997. The mortality rate was 7.3% and the ratio of male to female was 3.2 to 1. The early death were younger than late death(5th decade vs 7th decade). Mechanism of injury were motor vehicle accident(64%), followed by work-related, slip and fall, and unknown. The early death had a higher percentage of low GCS score, abnormal pupil reflex, other associated injury, hypotension, hypoxemia, hyperglycemia, midline shift, ventricle compression, skull fracture, and craniotomy compared with the late death. On the other hand, the late death had a higher incidence of hypocarbia, anemia, and hypernatremia than the early death. The main causes of death were primary intracranial lesions and hypovolemia in the early death and pneumonia, ARDS, and posttraumatic cerebral infarction in the late death.

기체 전기방전을 이용한 리액티브 블루 4의 분해에 관한 연구

목영선,조진오,이호원 제주대학교 공과대학 첨단기술연구소 2006 尖端技術硏究所論文集 Vol.17 No.1

Gaseous electrical discharge is an effective method available for the production of ozone and ultraviolet light. The wastewater treatment system of this study was designed to utilize both ozone and ultraviolet light produced by the electrical discharge for the degradation- of organic contaminants. The electrical discharge device (DBD reactor) consisted of a quartz cylinder, a coaxial ceramic tube inside of which a steel rod was placed (discharging electrode), and a steel wire that was helically wound around the quartz cylinder (ground electrode). The DBD reactor was immersed in the wastewater in order that the ultraviolet light could irradiate the wastewater. The ozone-containing gas from the DBD reactor was sparged throughout the wastewater. An anthraquinone-based dye, Reactive Blue 4, was chosen as the organic contaminant. The experimental results showed that the present system was very effective for the degradation of the organic contaminant. The energy requirement for the degradation was found to be 0.42kJ/mg, on the basis of 90% chromaticity removal.