냉각탑용 수분배기의 특성에 관한 연구

전유신,최석천,이용훈,김세현,정효민,정한식 경상대학교 해양산업연구소 2002 해양산업연구소보 Vol.15 No.-

The main purpose of this research is the investigation of water distributer. The water distributer of this research is installed in evaporative cooling tower system. The performance of this cooling tower system depend on the evaporative surface, and there are many kinds of methods for increasing the evaporative surface. In this research, we introduced the two kinds of spraying system, one is the hole type with hole diameter 1, 2 and 3mm, and the other is the spray nozzle types with nozzle tip diameter of 1 and 2mm. As the experimental results, the case of diameter 2mm showed the best performance.

쇄석 골재의 광물학적 및 화학적 특성과 알칼리-실리카 반응성

전쌍순,박현재,이효민,진치섭 釜山大學校生産技術硏究所 2002 生産技術硏究所論文集 Vol.61 No.-

본 연구에서는 쇄석 골재의 광물학적 및 화학적 특징과 알칼리-실리카 반응에 대한 골재의 유해 가능성을 연구하였다. 이를 위하여 알칼리-실리카 반응을 유발하는 광물들의 포함여부 및 이에 따라 잠재적으로 조기 열화현상을 유발할 수 있는 암석을 유형별(화성암, 변성암, 퇴적암 및 탄산염암)로 골재를 수집하였다. 암종 별로 선별하여 수집한 골재 내의 알칼리 반응성 유해 물질 존재 여부 확인 X선 회절분석(XRD)과 편광현미경에 의한 광물학적 방법을 사용하였다. 알칼리-실리카 반응성 유무해 판단을 ASTM C 227의 Mortar-Bar 시험방법에 의해 평가 분석하였고, 주 화학성분은 X선 형광분석기(XRF)로 실시하였다. In Korea, due to the shortcomings of natural aggregates and increasing needs of crushed stones, it is necessary to examine the alkali-silica reaction of the crushed stones. The purpose of this study is to analyze petrographic, chemical properties and alkali-silica reaction of crushed stones. This study was performed to investigate the alkali-silica reaction of crushed stones using chemical analysis, physical properties, XRD, XRF and mortar-bar method. As a result, most of test aggregates didn't show any reaction, but many test aggregates have common deleterious mineral. Therefore, there exists the possibility of chemical reaction in petrographic point of view.

[논문]반응성 골재의 입자 크기와 입도가 모르타르의 알칼리-실리카 반응 팽창에 미치는 영향

전쌍순,이효민,진치섭 釜山大學校生産技術硏究所 2003 生産技術硏究所論文集 Vol.62 No.-

골재의 알칼리-실리카 반응성을 판정하는 방법으로 모르타르 바 법 (Mortar-Bar method) 이 일반적으로 사용되고 있다. 본 연구에서는 알칼리 골재 반응성을 판정하는 모르타르 바 법 중에서 촉진시험법인 ASTM C 1260 시험방법을 이용하여 반응성 골재를 판별하고l 판별된 반응성 골재의 입자 크기와 입도가 모르타르의 알칼리-실리카 반응 팽창에 미치는 영향에 관하여 검토하였다. 그 결과I 반응성 골재의 입자 크기 및 입도에 상관없이 반응성 골재의 총표면적이 커질수록 팽창률도 증대하여,알칼리-실리카 반웅에 의한 팽창과 반웅성 골재의 총표면적과의 사이에는 상관관계가 있는 것을 확인할 수 있었다.

[논문]재생골재의 광물학적 및 화학적 특성과 동결융해 저항성

전쌍순,이효민,진치섭 釜山大學校生産技術硏究所 2003 生産技術硏究所論文集 Vol.62 No.-

급속한 산업화와 인구증가 및 대량소비에 따른 페기물에 의하여 초래되는 지구 환경오염을 위한 사회시스템의 구축이 필요함을 암시한다고 볼 수 있다. 본 연구에서는 지금까지 주로 저급재료로 사용되던 재생골재의 구성광물,화학조성 및 물리화학적 특성과 알칼리-골재 반응성 여부를 조사하고, 재생굵은골재의 대체율에 따른 콘크리트 강도와 동결융해 저항성을 검토하여 재생골재의 재활용을 위한 기초자료를 제시하고자 한다. 본 연구에 사용된 재생골재는 천연골재에 비교하여 공학적 기초 물성치에서 현저히 큰 차이는 나타내지 않았으며, 이를 사용한 재생콘크리트의 공학적 특성도 보통 콘크리트의 기준에 근접하는 것으로 나타났다.

활동기와 동면기 살모사의 위장관 점액세포내 점액질에 관한 조직화학적 연구

한현주,박래백,임영민,김효성,박경수,노영복 조선대학교 기초과학연구소 1990 自然科學硏究 Vol.13 No.1

살모사(Aekistrodon halys Pallas)의 위장관 점액세포내 점액질을 활동기와 동면기로 나누어 조직화학적으로 비교관찰하였다. 일반관찰을 위하여 H-E 염색을, 조직화학적 소견을 관찰하기 위하여 PAS reaction, Ab2.5 염색, AB1.0염색, AB2.5-PAS 염색, AB1.0-PAS 염색 AF1.7 염색 및 AF1.7-AB2.5 염색등을 시행하였다. 위(胃)는 표면점액세포와 점액경세포의 점액질을, 소장은 은롸롸 융모의 점액세포를 관찰한 결과를 다음과 같이 요약하였다. 1. 활동기와 동면기의 위점막에서는 현저한 차이는 없으나, 소장점막은 동면기에는 점막 주름수가 감소하고 높이가 낮아지며 점액세포가 위축되었다. 2. 위 표면점액세포는 활동기에 중성점액질과 약간의 Sialomucin을 포함한 산성점액질로 구성되었으나, 동면기에는 중성점액질과 Sialomucin이 약간 감소하였다. 3. 위 점액경세포는 활동기에 중성점액질만을 포함하고 있었으나, 동면기에는 Sialomucin을 포함한 산성점액질이 소량 검출되었다. 4. 소장 점액세포는 활동기에 산성점액질과 중성점액질로 구성되었으며 산성점액질에는 Sulfomucin과 Sialomucin이 포함되어 있었으나, 동면기에는 Sulfomucin과 Sialomucin이 다소 감소하였다. This study was performed in order to investigate the histochemical properties and compositions of the mucosubstances in the mucous of the gastrointestinal tract of Vipers, Agkistrodon halys Pallas, in active and hibernating phases. The specimens from stomach and small intestine were fixed in 10% neutral buffered formalin, embedded in paraffin wax, sectioned at a thickness of 4㎛, and stained with Hematoxyling-eosin for general histological observation and with PAS reaction, Alcian blue pH 2.5 or 1.0, Alcian blue pH 2.5-PAS or 1.0-PAS reaction, Aldehyde fuchsin pH 1.7, and Aldeliyde fuchsin pH 1.7-Alcian Blue pH 2.5 for histochemical finding. The mucous compositions in mucous cells of the gastrointestinal tract examined by their stain reaction were neutral mucin, acidic mucin, sulfomucin, sialomucin, The results obtained were as follows; The folds of the gastrointestinal tract in the hibernating phase, compared with the active phase, shrink and lower. Also, the shrinkage of epithelial cells were observed in the hibenating phase. The surface mucous cells of the stomach in the active phase composed mainly neutral mucin and a little amount of acidic mucin including sialomucin, but in the hibernating phase neutral mucin and sialomucin slightly decreased. The mucous neck cells of the stomach in the active phase constituted mainly neutral mucin, In the hebernating phase the mucous neck cells were composed of neutral mucin and a little amount of acidic mucin contained sialomucin. The mucous cells of the small intestine in the active phase consist of neutral mucin, acidic mucin including sulfomucin and sialomucin but in the hibernating phase sulfomucin and sialomucin slightly decreased.

도로판형교의 Life-Cycle Cost 최적설계

조효남,민대홍,조준석 漢陽大學校 工學技術硏究所 2000 工學技術論文集 Vol.9 No.1

본 연구에서는 강판형교에 대하여 총기대비용을 최소화하는 최적설계모델을 제안하였다. 총기대비용은 전체 공용기간을 고려하여 초기비용(설계비용, 개통전 검증재하시험비용, 건설비용), 유지보수비용 및 기대파괴비용을 포함하고 있다. 설계변수들에 대해 총기대비용을 최소화하는 문제로 정식화하였고, 거동제약조건은 휨파괴와 전단파괴의 형태로 되어 있다. 이러한 총기대비용 최적설계를 수행함으로써 효율적이고 합리적인 비용산정을 통해 총기대비용 설계의 근거를 제시하고 구조물 총기대비용에 관한 민감도 분석을 하였다. 수치해석을 통해 본 연구에서 제안된 총기대비용에 근거한 강판형교의 최적설계가 기존 초기비용 설계에 비해 훨씬 합리적이고 경제적인 설계가 될 것이며 향후 구조물 설계에서 추구해 나가야 할 차세대 성능기준 설계와 매우 밀접한 설계법임을 알 수 있다. This paper presents an optimum design model for minimizing the life-cycle cost (LCC) of steel plate girder bridges. The point is that it takes into account service life process as a whole, and thus the life-cycle costs include initial (design, testing, and construction) costs, maintenance costs and expected failure costs. The problem is formulated as that of minimization of expected total life-cycle cost with respect to the design variables. The performance constraints are considered in the form of flexural failure and shear failure. By processing the optimum LCC design the effective and rational basis is proposed for calculating the total LCC and the sensitivity analysis of LCC is performed. Based on a numerical example, it may be positively stated that the optimum LCC design of steel plate girder bridges proposed in this study provides a lot more rational and economical design, and thus the proposed approach will expedite the development of new concepts and design methodologies that may have important implications in the next generation performance-based design codes and standards.

Bacillus sp. FF-7에 의한 항산화물질 생산조건과 항산화 활성

차재영,김효정,전방실,박진철,옥민,조영수 한국응용생명화학회 2003 Applied Biological Chemistry (Appl Biol Chem) Vol.46 No.3

발효식품 시료로부터 분리된 세균을 DPPH(α,α¹-diphenyl-β-picrylhydrazyl) 전자공여능으로 항산화 활성을 측정하여 가장 활성이 강한 균주를 선별하여 형태학적, 생화학적, 생리학적 특성 및 16S rRNA 염기서열을 조사한 결과 Bacillus sp.으로 판명되어 FF-7로 명명하였다. DPPH 전자공여능법에 의한 Bacillus sp. FF-7이 생산하는 항산화물질의 최적 생산 배지조건은 탄소원 2% galactose와 질소원 1% tryptone 첨가였다. Bacillus sp. FF-7에 의해 생성된 항산화 물질의 활성을 DPPH 전자공여능, 흰쥐 각 조직 microsomal 실험계 및 linoleic acid 과 산화지질 실험계에서 malondialdehyde를 thiobarbituric acid(TBA)방법으로 측정하였다. 흰쥐 각 조직 microsomal 실험계에서 지질과산화에 대한 항산화 효과는 뇌(97.50%)>심장(79.95%)>신장(77.84%)>비장(77.47%)>고환(69.96%)>간장(62.45%) 순이였다. Linoleic acid의 과산화지질률 TBA법으로 측정한 결과 반응 4일째까지 억제 효과가 강하게 나타났으며, 동시에 대조구로 사용한 0.05% BHT 첨가구에서도 실험종료시까지 항산화 활성이 강하게 나타났다. The antioxidative activity of antioxidative substances produced from several bacterial strains isolated from fermented foods were tested by DPPH (α,α'-diphenyl-β-picrylhydrazyl) free radical scavenging activity. One of the strains showing the highest antioxidative activity was identified as Bacillus sp. based on the morphological, biochemical, physiological characteristics, and 165 rRNA sequence, and named FF-7. The molt optimal medium condition for the production of antioxidative substance from Bacillus sp. FF-7 was 2% galactose as carbon source and 1% tryptone as nitrogen source. The antioxidative substance produced from FF-7 in these cultural medium was also tested by in vitro experimental models, the peroxidation of linoleic acid and the peroxidation of rat tissues microsomes by using thiobarbituric acid (TBA) for assay of free rnalondialdehyde production. The antioxidative avtivity against lipid peroxidation of rat tissues microsomes was shown in the following order; brain 97.50% > heart 79.95% > kidney 77.84% > spleen 77.47% > testis 69.96% > liver 62.45%. The antioxidative substance produced from FF-7 on linoleic acid peroxidation by TBA method was effectively inhibited during four days, and 0.05% BHT(butylated hydroxytoluene) used comparative control was also effectively inhibited. Results showed that the highest antioxidative activity by DPPH method of antioxidative substance produced from Bacillus sp. FF-7 was obtained by supplementing 2% galactose as carbon source and 1% tryptone as nitrogen source in cultured medium, this substance effectively inhibited the formation of TBARS in brain microsome in vitro system and in linoleic acid peroxidation.

저압 증발형 압력 용기의 응력 변화 특성에 관한 연구

최석천,이용훈,전유신,허선철,정효민,정한식 경상대학교 해양산업연구소 2002 해양산업연구소보 Vol.15 No.-

The purpose of this research is to obtain the characteristics of strain and stress in the vacuum pressure vessel. The vacuum pressure vessel is used to many of industrial devices and cooling tower system. The vessel is under the vacuum pressure in this research, and we analyzed the stress on the vessel surface. As the experimental set up, we introduced the Static Strain Measurement(UCAM 70A, Kyowa) system. The environmental condition of vessel is reserved under vacuum pressure 50mmHg, and the vacuum pressure was made by a ejector pump system.

RF sputtering 법으로 제조된 CuInSe₂박막의 특성

김규호,김효준,이해석,김민호,정상현 嶺南大學校 工業技術硏究所 1998 工業技術硏究所論文集 Vol.26 No.1

CuInSe₂ thin films were prepared on Si(100) wafer by RF magnetron sputtering from powder target which was prepared by reacting high purity Cu₂Se and In₂Se₃(99.999%, Cu₂Se: In₂Se₃=1:1 mole ratio), in argon gas The XRD results suggest that deposited thin films were mainly composed of crystalline CuInSe₂ with the typical chalcopyrite structure, whereas film deposited showed the mixed phase of Cu₂Se+CuInSe₂at 50W. Deposited film showed (204), (220) preferred orientation at 50W and deposited films from 75W were strongly oriented along th e(112) plane. In the EDS analysis, Cu/In mole ratio of the thin films was decreased and Se/(Cu+In) mole ratio was increased with increasing RF power. The lattice parameters of a, c axis and c/a ratio of deposited films were decreased with increasing RF power. The grain size of the thin films measured by SEM became coarse with the increase of RF power.

그레이브스병에서 방사성 요오드 치료에 따른 갑상선 자극 호르몬 수용체 결합억제 면역글로불린(Thyrotropin Binding Inhibitory Immunoglobulin, TBII)의 변화

조영석,권기현,이준철,나소영,이효진,홍우정,이유선,김군순,송민호,김영건,노흥규 충남대학교 의학연구소 2003 충남의대잡지 Vol.30 No.2

Prediction of thrapeutic response to radioiodine in Graves' disease is poorly understood. Although thyrotropin binding inhibitor immunoglobulin(TBII) level is a strong index for relapse after antithyroid drug medication, conflicting results are reported regarding its prognostic significance in Graves' disease treated with RAI. This study is dengned to evaluate possible relationship between post-treatment hypothyroidism and TBII in Graves' disease treated with RAI. Fourty two patient with Graves' disease after radioiodine treatment were studied retrospectively. The subject were divided into hypothyroid group and euthyroid or hyperthyroid group. We evaluated the association of hypothyroidism and TBII with radioiodine treatment dose. The mean age of hypothyroid group was 48±11 years and euthyroid or hyperthyroid group was 47±12 years. There was no difference in two groups. And there was no significant difference in post- treatment TBII between two groups(49.9±28.5%, 29.9±14.3%, p-value >0.05). The treatment-dose had no influence on post-treatment thyroid state. Euthyroid or hyperthyroid group was done with 13.6±6.9mCi and hypothyroid group was 17.0±10.4mCi(p-value > 0.05). TBII had no prognostic significance on long-term hypothyrodism in Graves' disease treated with radioiodine. And, treatment-dose had no influence on post-treatment thyroid state.