나프록센 함유 방출제어형 패취의 제제설계 및 평가

이계주,홍석천,황성주 충남대학교 약학대학 의약품개발연구소 1999 藥學論文集 Vol.15 No.-

The purpose of this study is to prepare he controlled release adhesive patch containing naproxen. Pressure-sensitive adhesive (PSA)-type patch was fabricated by casting of polyisobutylene (PIB) and mineral oil in toluene. Membrane-controlled release (MCR)-type patch was prepared by the attachment of the controlled release membrane on the PSA-type patch. The membrane was mainly composed of Eugragit. polyethylene glycol(PEG) and glycerin. The drug release profile and skin permeation test with various patches were evaluated in vitro. The release of naproxen from PIB-based PSA-type patch with various loading dosed fitted Higuchi's diffusion equation. However, the permeation of naproxen through hairless mouse skin from PSA-type patch followed zero-order kinetics. In MCR-type patch, thickness of controlled release membrane affected on the drug release rate highly. In the composition of membrane the release rate was decreased as the ratio of Eudragit increased. The drug release from the MCR-type patch followed zero order kinetics. The permeation of naproxen through hairless mouse skin from MCR-type patch showed lag time for the intial release period and didn't fit the zero-order kinetics.

Urapidil, Labetalol의 투여가 기관내 삽관시 심혈관계에 미치는 영향

신용섭,윤석화,손수창,이원형,이정은,황원재,김만수,김영주,김혜자,최세진 충남대학교 의과대학 지역사회의학연구소 1994 충남의대잡지 Vol.21 No.2

We have examined the comparative efficacy of small doses of intravenous urapidil and labetalol in blunting hemodynamic response to endotracheal intubation and surgical incision in 30 patients without cardiovascular diseases. After intravenous urapidil 0.2 mg/kg or labetalol 0.2 mg/kg anesthesia was induced with thiopental 5mg/kg. Endotracheal intubation was facilitated by vecuronium 0.15 mg/kg with priming principle and anesthesia was maintained with enflurane and nitrous oxide in oxygen. Systolic, diastolic and mean arterial pressure and heart rate were measured before administration of the drugs, 5 minute after administration, just prior to endotracheal intubation and 1, 3, 5, 10 minute after intubatin. Also the peak blood pressures and heart rate within 10 minutes after surgical incision were measured. Endotracheal intubation and surgical stimulation were associated with significant increases in blood pressures and heart rate in both urapidil and labetalol group. Comparison of the changes in systolic, diastolic, and mean artrial pressures and heart rate between urapidil and labetalol group showed no significant difference except peak systolic pressure after surgical incision. It is concluded that the pressor response to endotracheal intubation and surgical stimulation are not influenced significantly by urapidil 0.2 mg/kg or labetalol 0.2 mg/kg. However, urapidil and labetalol preloading may be similarly effective in the blunting of the increases in blood pressures with larger doses of the durgs during anesthetic induction.

고도정수처리 공정에서의 천연유기물질 특성변화 및 소독부산물 전구물질의 제거특성 평가

노재순,손희종,박은주,황영도,최동훈,배석문,신판세 慶星大學校 環境問題硏究所 2002 環境硏報 Vol.12 No.1

In this research the movement and apparent molecular weight distribution of hydrophilic/hydrophobic organic matters in advanced water treatment process were investigated using the raw water of Maeri area, located in downstream of Nakdong river, and the variation of the disinfection by-product formation potential was also investigated. In the raw water used in experiments, the content of BDOC (biodegradable dissolved organic carbon) in dissolved organic carbon (DOC) was about 39%, and this value is far above a normal, Pre-ozone treatment showed an increase of 40% in the BDOC content, and this means that biodegradability was remarkably increased by ozone treatment BDOC concentration in BAC treated water was 0.09 mg/L, which means 84% of BDOC removal rate compared with that in post-ozone treated water. The variation of chlorine disinfection by-product formation potential in each process unit of water treatment process was analyzed. TOXFP concentration in raw water was 449 ㎍/L, and the contents of THMFP and HAAFP among TOXFP were 24% and 23%, respectively. The removabilities of these materials BAC process had an order of TOXFP > HAAFP > THMFP. BAC process was less effective for THMFP than others. The distribution of hydrophilic organic matters were evaluated in each treatment process. Hydrophilic and hydrophobic matters in the raw water had a ratio of 50 : 50, and the ozone treatment decreased the content of hydrophobic matters. The BAC treatment made the ratio 85:15. These mean that the removal of hydrophilic matters is more difficult than that of hydrophobic materials in water treatment process. In addition the portions of humic and fulvic acid in hydrophobic matters were analyzed. Fulvic acid a large portion among hydrophobic matters in the raw water, and the portion was 78%. Ozone treatment was more effective on the removal of fulvic acid than humic acid. After BAC treatment, the concentration of residual fulvic acid was high than humic acid. Chlorine disinfection by-product formation for hydrophilic and hydrophobic mattrts was compared in each process unit. in the raw water TOXFP and THMFP formation for hydrophobic matter was higher, and HAAFP was highly formated for hydrophobic matter. After post-ozone or BAC treatment, chlorine disinfection by-product formation has high potential for hydrophobic matters. Comparing humic and fulvic acids, chlorine disinfection by-product formation potential was higher for humic acid than for fulvic acid in all processes. In the comparison of the reactivity with chlorine disinfection by-product per unit DOC, THMFP and DOXFP showed higher reactivity with hydrophobic matter than with hydrophilic matter in all processes, and HAAFP was highly reacitive with hydrophilic matter. Apparent molecular weight distributions of organic matters were investigated in each process step.The content of low molecular weight organic matters less than 1000 Da in DOC was high in all processes except raw water, but molecular weight organic matters more than 1000 da was higher than molecular weight organic matters less than 1000 Da in the formation potential of chlorine disinfection by-product.

Development Technology of Concrete Container Characteristic Evaluation

Seok-Ju Hwang,Younghwan Hwang,Mihyun Lee,Jung-Kwon Son,Changgyu Kim 한국방사성폐기물학회 2023 한국방사성폐기물학회 학술논문요약집 Vol.21 No.2

At domestic nuclear power plant, concrete containers are stored to store waste generated before waste acceptance criteria (WAC) was established. Concrete container store concentrated waste liquid and waste resin. In order to disposal radioactive waste to a disposal site, it is necessary to conduct a characteristic evaluation inside the waste to check whether it satisfies the WAC. Two types of concrete containers are stored: round and square. The round type is filled with one 200-liter drum, and the square type is filled with four 200-liter drums. In the case of a round shape, the top lid is fastened with bolts, so it is possible to collect samples after opening the top lid without the need for additional equipment. However, in the case of a square shape, there is no top lid, and concrete is poured to cure the lid, so the separate equipment for characteristic evaluation is required. It is necessary to install a workstation for sample collection on the top of the concrete container, equipment for coring the top of the concrete container, and a device to prevent concrete dust scattering. Currently, the design of equipment for evaluating the characteristics of concrete containers has been completed, and equipment optimization through mock-up test will be performed in the future.

Development of Irrigation System for Roller-Type Onion Pot-Seeding Machine

( Seok-joon Hwang ),( Ju-yeon Lee ),( Ju-seok Nam ) 한국농업기계학회 2018 한국농업기계학회 학술발표논문집 Vol.23 No.1

In this study, a modular type irrigation system applicable to the existing roller-type onion pot-seeding machine was developed, and optimal operating conditions were derived. The irrigation type of the developed irrigation system is drip-type and it can support irrigation by each pot tray cell. The irrigation system consists of water tank, water pump, irrigation pipe, irrigation height regulator, hand valve, etc. Each component was selected considering durability and economical efficiency. Factorial experiment was performed by setting the hole diameter of the irrigation pipe and the hand valve open/close as a experimental factors. In the experiment, the optimal result was obtained in the condition of 1.0 mm of the hole diameter and closed hand valve. It is possible to reduce labor and do initial irrigation by applying the developed irrigation system to the existing roller-type onion pot-seeding machine. Furthermore, the productivity and efficiency of onion cultivation can be increased.

Development Trend of Radwaste Characterization Technology for Safe Disposal

Seok-Ju Hwang,YoungHwan Hwang,Cheon-Woo Kim 한국방사성폐기물학회 2022 한국방사성폐기물학회 학술논문요약집 Vol.20 No.2

For the disposal of radioactive waste generated from nuclear power plants, characterization of radioactive waste is essential. For characterization, samples of radioactive waste are directly collected or an indirect method is used through X-ray, etc. Through indirect analysis, which is a non-destructive method, the density, filling height, homogeneity and inter structure of the waste container can be analyzed. Currently, foreign institutions are in the process of developing a technology to perform characterization of radioactive waste through indirect analysis. In particular, research on improving internal image accuracy through image analysis techniques, improving measurement methods and enhancing portability for field application is ongoing. Through the review of such technology development trends, it will be utilized in the development of domestic radioactive waste disposal technolgy.

Study on Optimization Gaseous Effluent Evaluation Point of Radiological Environmental Impact Assessment

Seok-Ju Hwang,Siyoung Kim,Deuk-man Kim,Jung-Kwon Son 한국방사성폐기물학회 2023 한국방사성폐기물학회 학술논문요약집 Vol.21 No.2

Domestic nuclear power plants conduct radiological environmental impact assessments every year in accordance with the Nuclear Safety and Security Commission (NSSC) notice. Among them, gaseous effluents are evaluated for their effects due to inhalation, external exposure in the air, exposure from ground surface deposits, food intake. In order to evaluate the impact of this exposure pathway, an evaluation point for each pathway must be selected. In the case of evaluation points, each country has different evaluation points. In the case of Korea, the evaluation point is calculated on the assumption that one lives 365 days a year at the EAB and consumes food from the nearest production area. In the case of the United States, external exposure and inhalation are evaluated at the site boundary or the nearest residential area, and food intake is evaluated by assuming that food produced in the nearest residential area or the nearest production area is consumed. Currently, the dose evaluation is optimized and selected so that EAB evaluation point for each site includes 16 direction evaluation points for each unit. In the E-DOSE60 program currently under development, the evaluation point was selected by calculating 16 direction x number of units without optimization. The food intake evaluation point was selected as the point that satisfies the minimum farmland area of the U.S. NRC NUREG-1301 and is the shortest distance from the site. The location of the production point from multiple units in included all 16 directions for each unit and quantity of evaluation points was optimized to satisfy the shortest distance. It can contribute to improving the reliability of the E-DOSE60 program currently under development by selecting new evaluation points for evaluating inhalation and external exposure evaluation and selecting optimized dose evaluation points for each site for evaluation by ingestion.

Study on Improvement of Gaseous Effluent Evaluation of Radiological Environmental Impact Assessment

Seok-Ju Hwang,Siyoung Kim,Deuk-man Kim,Jung-Kwon Son 한국방사성폐기물학회 2023 한국방사성폐기물학회 학술논문요약집 Vol.21 No.1

K-DOSE60, a off-site dose calculation program currently used by khnp, is performing evaluation based on the gaseous effluent evaluation methodology of NRC Reg. Guide 1.109. In particular, H-3 and C-14, which are the major nuclides of gaseous effluent, are evaluated using a ratio activity model. Among them, H-3 is additionally evaluating the dose to OBT (Organically Bound Tritium) and HT as well as HTO (Triated water). However, NRC Reg. Guide 1.109 is a methodology developed in the 1970s, and verification was performed by applying the evaluation methodology of H-3 and C-13 presented by IAEA TRS-472 in 2010 to the current K-DOSE60. The IAEA TRS-472 methodology also includes OBT and HT for H-3. In order to apply the ratio radioactivity model presented in IAEA TRS-472, the absolute and relative humidity were calculated using the weather tower of the nuclear site and used for H-3 evaluation. For the dose evaluation of HT, the previously used Canada Chalk River Lab. (CNL) conversion factor was used. For atmospheric carbon concentration, the carbon concentration presented in IAEA TRS-472 was used, not the carbon concentration in the 1970s of NRC Reg. Guide 1.109. It was confirmed that the K-DOSE60, which applied the changed input data and methodology, was satisfied by performing comparative verification with the numerical calculation value.

Review on Radiological Environmental Impact Assessment Regulatory Trend

Seok-Ju Hwang,Siyoung Kim,Deuk-man Kim,Jung-Kwon Son 한국방사성폐기물학회 2023 한국방사성폐기물학회 학술논문요약집 Vol.21 No.1

In 2022 and 2023, the Korea Institute of Nuclear Safety (KINS), a regulatory body, revised the regulatory guidelines for off-site dose evaluation to residents, marine characteristics surveys around nuclear facilities, and environmental radiation surveys and evaluation around nuclear facilities. In addition, the NRC, a US regulatory body, has revised regulatory guide 1.21 (MEASURING, EVALUATING, AND REPORTING RADIOACTIVE MATERIAL IN LIQUID AND GASEOUS EFFLUENTS AND SOLID WASTE) to change environmental programs for nuclear facilities. The domestic regulatory guidelines were revised and added to reflect the experience of site dose evaluation for multiple units during the operation license review of nuclear facilities, the resident exposure dose age group was modified to conform to ICRP-72, and the environmental monitoring plan was clarified. In the case of the US, the recommended guidelines for updating the long-term average atmospheric diffusion factor and deposition factor, the clarification of the I-131 environmental monitoring guidelines for drinking water, and the clarification of the procedures described in the technical guidelines when changing environmental programs have been revised and added. Through such regulatory trend review, it is necessary to preemptively respond to changes in the regulatory environment in the future.

Spray Pattern Analysis for a Centrifugal Fertilizer Distributor with Two Shutter Holes

Seok-Joon Hwang(황석준),Jeong-Hyeon Park(박정현),Ju-Yeon Lee(이주연),Ki-Duck Kim(김기덕),Beom-Soo Shin(신범수),Ju-Seok Nam(남주석) 한국기계가공학회 2019 한국기계가공학회지 Vol.18 No.10

In this study, the spray pattern of a centrifugal fertilizer distributor with two shutter holes was analyzed and an effective driving width that satisfies proper spray uniformity was derived. The centrifugal fertilizer distributor was mounted on a tractor with a rated power of 23.7 kW and static and dynamic spray pattern tests were performed according to the standard procedure proposed by the American Society of Agricultural and Biological Engineers Standard ASAE S341.5. The height of the fertilizer distributor was 80 cm from the ground and the PTO (power take-off) shaft speed of the tractor was fixed at 540 rpm. The fertilizer scattered in space was collected using 275 evenly spaced collectors at shutter opening ratios of 25%, 50%, 75%, and 100%. The spray pattern was analyzed via the amount of sprayed fertilizer at each collector location and the coefficient of variation was used as an indicator of spray uniformity. Using the analyzed spray pattern, the effective driving width that satisfied less than 15% of the coefficient of variation was derived for different tractor driving patterns (race track mode, back and forth mode). From the results, spray uniformity increased as the shutter opening ratio decreased. The largest effective driving width was 8 m at a shutter opening ratio of 25% for both driving patterns.