적막에 대하여 외 1편

서원동 본질과 현상사 2011 본질과 현상 Vol.25 No.-

아크릴 , 에폭시 , 우레탄 및 SBR 계 라텍스를 혼합한 에틸렌 비닐아세테이트계 에멀젼 수지의 물리적 특성

서원동 한국고무학회 2000 엘라스토머 및 콤포지트 Vol.35 No.3

SBR, polyurethane, acryl and epoxy latex were separately mixed with ethylene-vinylacetate emulsion(EVA) in the range of 0∼50 wt%. For the mixtures, the various physical properties such as defoamerability, mechanical property, and water resistance were experimentally examined. The excellent defoamer was BYK-021 and the appropriate use of it was 0.3 phr for the total components. The shrinkage of compounds was influenced by the compatability of resins and the formation of voids. The mechanical properties was related to the cohesive force of resin particles, the coagulation of cement particles and the co-bonding of resin particles with cement particles. Mixing latex separately showed better properties then non-mixing in the shrinkage ratio, flexural strength, adhesive strength, and impact strength. The water resistance of composites mixed with cement was worse than that of EVA resin.

모닥불 - 겨울, 탑골공원 노인들 외 1편

서원동 본질과 현상사 2009 본질과 현상 Vol.18 No.-

쉰일곱 편의 悲歌 1 - 겨울 江가에서 외2편

서원동 본질과 현상사 2012 본질과 현상 Vol.29 No.-

고무의 가교제의 종류와 그 작용

서원동 한국고무학회 1977 엘라스토머 및 콤포지트 Vol.12 No.2

SBR , 폴리우레탄 및 에폭시 라텍스를 혼합한 폴리초산비닐 에멀젼 수지의 물성에 관한 연구

서원동 ( Won Dong Suh ) 한국고무학회 1998 엘라스토머 및 콤포지트 Vol.33 No.3

N/A SBR latex, polyurethane latex and epoxy latex were separately mixed with polyvinyl acetate emulsion. The various physical properties were examined for the mixtures. Epoxy mixtures gave a transparent film. Both polyurethane and SBR mixtures showed opaque film with high viscosity. In S13R. and polyurethane increase in hardness was dependent on the evaporation rate of water, but in epoxy it was dependent on the degrees of crosslink. Epoxy`s showed excellent water-resistance. SBR showed a goad flexural strength and impact strength. When vinyl acetate emulsion was mixed with less than 10% latex paper tube showed the ductile fracture, but over latex content 20%, it showed the brittle fracture.

Flow Cytometric Human Leukocyte Antigen-B27 Typing with Stored Samples for Batch Testing

서보영,원동일 대한진단검사의학회 2013 Annals of Laboratory Medicine Vol.33 No.3

Background: Flow cytometry (FC) HLA-B27 typing is still used extensively for the diagnosis of spondyloarthropathies. If patient blood samples are stored for a prolonged duration,this testing can be performed in a batch manner, and in-house cellular controls could easily be procured. In this study, we investigated various methods of storing patient blood samples. Methods: We compared four storage methods: three methods of analyzing lymphocytes (whole blood stored at room temperature, frozen mononuclear cells, and frozen white blood cells [WBCs] after lysing red blood cells [RBCs]), and one method using frozen platelets (FPLT). We used three ratios associated with mean fluorescence intensities (MFI) for HLAB27assignment: the B27 MFI ratio (sample/control) for HLA-B27 fluorescein-5-isothiocyanate (FITC); the B7 MFI ratio for HLA-B7 phycoerythrin (PE); and the ratio of these two ratios,B7/B27 ratio. Results: Comparing the B27 MFI ratios of each storage method for the HLA-B27+ samples and the B7/B27 ratios for the HLA-B7+ samples revealed that FPLT was the best of the four methods. FPLT had a sensitivity of 100% and a specificity of 99.3% for HLA-B27assignment in DNA-typed samples (N=164) when the two criteria, namely, B27 MFI ratio >4.0 and B7/B27 ratio <1.5, were used. Conclusions: The FPLT method was found to offer a simple, economical, and accurate method of FC HLA-B27 typing by using stored patient samples. If stored samples are used, this method has the potential to replace the standard FC typing method when used in combination with a complementary DNA-based method.

신기능 저하 환자의 조영제 신독성 예방을 위한 N-acetylcysteine 복용과 수액요법의 비교

서정숙 ( Jeong Sook Seo ),전혜정 ( Hae Jung Jun ),구호석 ( Ho Seok Koo ),이원동 ( Won Dong Lee ),강선우 ( Sun Woo Kang ),김영훈 ( Yeong Hoon Kim ),김양욱 ( Yang Wook Kim ),이정녀 ( Jeong Nyeo Lee ),박성한 ( Sung Han Park ),이준식 대한내과학회 2007 대한내과학회지 Vol.73 No.4

목적: 조영제로 인한 신부전(contrast induced nephropathy, CIN)은 신기능 저하 환자에게 있어 급성신부전의 중요한 원인 중 하나이다. 이러한 CIN의 예방 방법으로서 N-acetylcysteine (NAC)와 수액 공급 병합요법이 효과적으로 알려져 있다. 그러나 단독 수액요법 또한 예방효과가 있다고 보고되고 있다. 이에 저자들은 신기능저하 환자에게 있어 단독 경구 NAC 투여가 단독 수액요법과 비교하여 CIN의 예방에 유사한 효과가 있는지, 혈관 확장제인 nitric oxide의 요중 배설에 차이가 있는지를 비교함으로써 향후 충분한 수액요법을 하기 힘든 경우, 경구 NAC 투여만으로 CIN의 예방이 가능한가를 알아보기 위해 본 연구를 시행하였다. 방법: 비이온성, 저삼투성 조영제를 이용한 방사선학적 검사(복부 컴퓨터 단층 촬영 또는 관상동맥 조영술)가 필요한 27명의 신기능 저하 환자를 대상으로 하였다. CIN의 정의는 급성 신부전이 발생할 특별한 원인 없이 조영제 사용 전에 비교하여 사용 후 48시간 내에 혈청크레아티닌이 0.5 mg/dL 이상 증가하는 것으로 정의하였다. 이 환자들 중 11명은 NAC 600 mg을 하루 두 번 복용시켰고, 16명은 0.45% saline을 1 mL/kg/Hr의 비율로 조영제를 투여하기 전 12시간 동안과 조영제 사용 후 12시간 동안 투여하였다. 환자들을 대상으로 조영제를 투여하기 전과 투여 후의 혈청 크레아티닌, FENa, 크레아티닌 청소율을 측정하였다. 그리고 NAC 투여한 5명과 수액 군의 10명을 대상으로 조영제 사용 전과 사용 48시간 후의 요중 nitrite를 측정하였다. 결과: 사용한 조영제의 평균 양(100.9±54.8 vs 114.7±38 mL; p=0.43) 및 기본 혈청 크레아티닌의 수치는 양 군에서 차이가 없었다(2.31±1.59 vs 2.18±1.4 mg/dL; p=0.98). CIN의 발생 빈도는 NAC군과 수액요법군에서 18.2%와 12.5%로 두 군 간의 유의할만한 차이가 없었다(p=1.0). 또한 조영제 사용 전 혈청 크레아티닌이 CIN발생에 가장 중요한 위험 요소였다. 뇨 nitrite/크레아티닌 비(μmol/mg)는 NAC군에서는 투여 전, 후 각각 1.26±0.57, 1.43±0.64였고, 수액요법군에서는 0.80±0.40, 1.18±0.60로 두 군 간의 유의한 차이는 없었다. 조영제 노출 후 수액용법군에 비해 NAC군에서 FENa는 증가하였다(p=0.04). 결론: 단독 경구 NAC 투여 역시 CIN의 예방에 효과적이었다. 이에 따라 수액투여가 금기시 되는 신기능 저하 환자에 있어 CIN의 예방에 NAC 단독요법이 효과적일 것으로 사료된다. Background: Contrast induced nephropathy (CIN) is an important cause of acute renal failure in patients with renal dysfunction. We investigated whether oral NAC alone was sufficient to prevent CIN to the same extent as hydration in patients with renal dysfunction, and whether these treatments resulted in diffierences in the urinary excretion of nitric oxide, a vasodilator. Methods: A total of 27 patients with renal dysfunction, who underwent radiographic examination with nonionic and low osmolar contrast, were randomly assigned to receive either NAC (600 mg orally twice daily; N=11) or 0.45% saline hydration (1 mL/kg/Hr; N=16) 12 hours prior to and 12 hours after the contrast procedure. We measured serum creatinine (sCr), fractional excretion of sodium (FENa), creatinine clearance (CCr), and urinary nitrite before and after contrast administration. Results: The mean volume of contrast used was similar in the two groups (100.9±54.8 mL vs 114.7±38 mL; p=0.43), as was baseline sCr in the two groups (2.31±1.59 mg/dL vs 2.18±1.41 mg/dL; p=0.98). Treatment did not significantly affect the incidence of CIN, with 18.2% and 12.5% in the NAC group and hydration group, respectively (p=1.0). The urinary nitrite/creatinine ratio (μmol/mg) was 1.26±0.57 and 1.43±0.64 at baseline and 48 hours after contrast exposure in the NAC group, respectively, and 0.80±0.40 and 1.18±0.60 in the hydration group, respectively, which were not significantly different. FENa increased significantly after contrast exposure in the NAC group compared with hydration group (p=0.04) Conclusions: NAC alone may prevent CIN. When bolus hydration is contraindicated in patients with renal dysfunction, administration of NAC alone may be sufficient.(Korean J Med 73:361-367, 2007)

SBR , 폴리우레탄 및 에폭시 라텍스를 혼합한 폴리초산비닐 에멀젼 수지의 점성에 관한 연구

최상구,서원동,박인숙 한국고무학회 1998 엘라스토머 및 콤포지트 Vol.33 No.2

SBR latex, polyurethane latex and epoxy latex were mixed with polyvinyl acetate emulsion in 0∼15%(wt. %). For the mixtures, the viscous properties were examined. The viscosity was influenced by the dispersed phase and the chain structures of polymer, and decreased with the rising of temperatures. The viscosity was increased with mixing of epoxy latex, but decreased with addition of SBR latex or polyurethane latex. Thixotropic index was influenced on the size of micelle and hydrogen bond. The thixotropic index was increased with mixing of epoxy latex or polyurethane latex within 5%, but keep up equality over that. The thixotropic index was decreased with mixing of SBR latex within 5%, but keep up equality over that. The relative viscosity were influnced on the activity of molecule and the interference of dispersed phases, was increased with the rising of temperatures. The relative viscosity was decreased with mixing of epoxy latex, but increased with mixing of SBR latex or polyurethane latex.

가황구무에 함유된 충진제에 대한 적외선분광분석 연구

백남철,서원동 한국고무학회 1978 엘라스토머 및 콤포지트 Vol.13 No.2

The measurement of the infrared absorption spectrum of supporting reinforcing filler which is oltained from the domestic area of Korea, Japan and U.S.A., is used by the method of KBr pellet. As a result of experiment, each absorption fond of the filler had appeared differently, because of each filler is consisted of different chemical composition, different crystalline form, different method of preparation, and the different ways of use etc. According to the above phenomena, each filler seems to have a different characteristic infrared absorption band, We can find what filler is used for sample rubber.