PE배관의 융착 강도에 관한 연구

전흥원,김용수,태순호 한국산업안전학회 2002 한국안전학회지 Vol.17 No.2

At present, the Polyethylene piping, on supporting LNG is widely used because of it's disposition which are anti-corrosion, flexible and so on. However, it has a few kinds of risk which are the possibility of piping leak, the character of easily corroded and so on. For giving solution, this study is intended to experiment the intension of the PE pipe after melted and when it is melting, the condition which are temperature and pressure is changed. the melting condition in temperature and pressure is adapted identically. After melting, it's joint is tested as intension. The result is that the effect of temperature in intension is more effective than pressure. In 210℃, 20㎏/㎠ condition, the melting intension has the highest. Compare to the Butt melting joint and the Saddle melting joint, the former was 214㎏/㎠ and the latter was 50㎏/㎠(bead 2~3㎜) and 73㎏/㎠(bead 5~7㎜). It means that the Butt melting method has more intensive than saddle. Consequently, the result shows that the liability and safety when PE pipe melting method is used will improve in pipe installation.

턴디슈용 SiC 코팅材의 특성에 관한 硏究

김행식,최태현,이용구,전병세 경남대학교 신소재연구소 1995 論文集 Vol.5 No.-

턴디쉬 내장용으로 사용할 내화재료의 여러 가지 특성들을 시험하였다. 납석 70%, 점토 10% 그리고 탄화규소 20%을 혼합하여 18 가지의 조성을 가지는 시험편을 제조하였다. 탄화규소는 각각 순도 85%와 65%인 유럽산, 일본산, 중국산을 택하여 최종 제품에 미치는 영향을 알아보았다. 여러 가지 시험의 결과 10% 탄화규소를 포함한 시험편의 경우 점토질 내화벽돌 보다 수명이 2배 정도 향상되었으며 차지당 용손 두께도 1.5∼1.7㎜/ch였다. Various properties of refractory materials for the tundish lining were examined. The refractory samples with 18 different composition were prepared by mixing powders of 70 wt.% pyrophyllite. 10 wt.% clay and 20 wt.% Sic. SiC was selected from three sources, European. Japanese and Chinese-made, having 85% and 65% purities, to examine their effects on the final properties. As a results of several testings. the sample with 10% SiC(European1 was best suitable for tundish lining as a refractory coating materials. The wear depth was 1.2-1.5 mm per charge at the wall and 1.7 mm per charge a t the slag line, having shown that this service life was about 2 times longer than the ordinary lining made of clay firebricks(SiO₂-Al₂O₃).

Agar-Gel Immunodiffusion Test를 이용한 돼지흉막폐염(Swine Pleuropneumoniae)의 진단에 관한 연구

심항섭,장경수,조용성,전무형 충남대학교 수의과대학 동물의과학연구소 1994 動物醫科學硏究誌 Vol.2 No.-

To establish an effective diagnostic measure for detection of the antibodies against Actinobacillus pleuropneumoniae, that is the primary agent of swine pleuropneumoniae, the methods for micro-agglutination test(MAT) and agar-gel immunodiffusion test(AGID) were improved and standarized and the comparative studies were carried out. The results obtained through the experiments were summarized as follows. 1. The rabbit hyperimmune sera to reference serotypes 1 to 6 were cross-tested with MAT and AGID. The range of antibody titers on MAT was 80 to 1280, showing the cross-reaction in serotypes 3, 4, 5 and 6. In AGID, the range of antigen titers was 8 to 32, and cross-reaction was observed in serotype 5. The optimal concentration of antigen MAT were 1.25㎎/㎖ 2. In AGID, the most promising antigen and the buffer for agar-gel were EDTA-treated antigen and 0.05M tris buffer(pH 7.2), respectively. 3. By the tests for 200 swine sera, it was found that the accumulative frequency of positive reaction for the 6 serotypes were 240 in MAT and 163 in AGID. 4. when compared the results of AGID with those of MAT for 200 swine sera, all sera with MAT titier under 20 were negative in AGID. Of the sera with MAT titer 40 and 80, 24.7% and 93.9% were positive in AGID, respectively. All sera with MAT titer over 160 showed positive in AGID. 5. In conclusion, the established MAT showed high sensitivity but low specificity, whereas AGID revealed low sensitivity but high specificity. The established AGID test was considered very efficient for detection of antibodies and serotyping of swine sera.

상수에서 조류 및 조류 부산물질 제거방안

신항식,전항배 嶺南大學校 環境問題硏究所 1998 環境硏究 Vol.17 No.2

농산물 물류센터의 재무투자분석

강준구,한두봉,양승룡,정복조 韓國農業政策學會 1999 농업경영정책연구 Vol.26 No.2

이산화염소의 상수수질 개선효과

배병욱,전향배,임봉수 大田大學校 産業技術硏究所 1995 산업기술연구소 論文集 Vol.1995 No.9

본 연구에서는 이산화염소의 수질개선 효과와 이산화염소 부산물의 성상을 정량적으로 조사하였다. 발생기 이산화염소와 대청용수의 반응실험 결과에 의하면, 이산화염소를 2 mg/l 투입할 경우 반응 6시간후 시료의 TON(threshold odor number)은 100에서 50으로 감소하였으며, 반응 12 시간동안에 약 80%의 chlorophyll-a가 감소하였다. 한편, 청주취수탑 표층수의 DOC(dissolved organic carbon)는 Duozon 투입량 1.5 mg/l에서 14시간 동안 반응시켰을 때, 약 30% 감소하였다. 그러나, Duozon 투입량 3 mg/l까지는 투입량 증가에 따른 DOC 감소가 크지 않았다. In this study, the effect of chlorine dioxide(ClO₂) on the improvement of drinking water quality was investigated. In addition, by-products of chlorine dioxide, such as chlorine, chlorate, and chloride ion, were quantified by using ion chromatography. At chlorine dioxide dosage of 2 mg/l, TON(threshold odor number) of raw water decreased from 100 to 50 after 6 hrs of reaction and about 80% of chlorophyll-a decreased after 12 hrs. On the other hand, DOC(dissolved organic carbon) concentration decreased to 70% of initial value after 14-hr reaction at Duozon dosage of 1.5 mg/l. However, decrease in DOC was not remarkable as increasing Duozone dosage up to 3 mg/l.

생물학적 및 미생물전기화학적 수소 메탄화

권혜정, 박준규, 전항배 충북대학교 산업과학기술연구소 2018 산업과학기술연구 논문집 Vol.32 No.2

본문 참조

질산화 반응에 미치는 SRT 및 HRT의 영향

박상민,박노백,전항배 충북대학교 건설기술연구소 2004 建設技術論文集 Vol.23 No.1

The effects of HRT and SRT on nitrification in activated sludge system were investigated at the temperature range of 10 to 25℃. HRT and SRT for lab-scale aeration tank were varied in the range of 4.5 to 13 hours and 7.5 to 20 days, respectively. Continuous aeration tanks fed with domestic sewage were supplied with oxygen up to 5 ㎎/L for efficient nitrification. In the steady state of operation period, maximum specific ammonium utilization rate by nitrifiers was 0.08g-NH₄/g-VSSㆍday at 20t however nitrification rate declined with the decrease of temperature. According to the decrease of SRT as well as temperature, biomass in the aeration tanks also decreased. Therefore, operating SRT and HRT have to be extended at low temperature. With the fixation of SRT to 7.5 days, 13 hours or higher HRT was required to achieve the nitrification efficiency of 90% at 10℃. Furthermore, SRT of aeration tank affect nitrification efficiency more by the temperature changes. In spite of 20 days or higher SRT, nitrification efficiency was 60% below 15℃. Accordingly, nitrifiers in the activate sludge system required over 8 hours of HRT and 20 days of SRT for nitrifying the 60% of influent ammonia below 15℃, especially in winter season.

서울의 Penicillinase Producing Neisseria gonorrhoeae 발생빈도(1998)

김재홍,김준호,반재용,이정우,황성주,정준규,정성태,강진문,조흔정,홍창의,정혜신,이한승,김이선,이봉길,이종호,선영우,한기덕,윤성필,이성훈,안종성,박석범,문승현,조항래,김형섭,류지호,황재영,박준홍,손상욱 한양대학교 의과대학 2001 한양의대 학술지 Vol.21 No.1

In recent years, gonorrhea has been pandemic and remains one of the most common STDs in the world, especially in developing countries. For the detection of a more effective therapeutic regimen and assessing the prevalence of Penicillinase Producing Neisseria gonorrhoeae(PPNG), we have been trying to study the patients who have visited the Venereal Disease Clinic of Choong-Ku Public Health Center in Seoul since 1980 by menas of the chromogenic cephalosporin method. In 1998, 93 strians of N. genorrhoeae were isolated, among which 60(64.5%) were PPNG. The prevalence of PPNG in Seoul, which had been decreased to 39% in 1996 after a peak of 74.3% in 1993, is increased to 64.5% in 1998.

완속여과 시스템에서 입자 제거와 손실수두(headloss)의 관계

신승식,홍진아,전항배 충북대학교 건설기술연구소 2003 建設技術論文集 Vol.22 No.1

The operational performance of slow sand filters can be considerably improved by the application of a layer of non-woven synthetic fabric to the top surface of the sand media. This improvement is manifested in terms of an increased filter run time and the avoidance of headloss development within the sand media. The relationship between particulate removal and headloss development were investigated with two pilot-scale slow sand filters(filter A and filter B(ACF)) of which diameter was 140 mm and packed with sand in the depth of 850 ㎜. One of the filters was amended by covering the surface of slow sand filters with a ACF(activated carbon fiber) of which specific surface area was more than 1000 ㎡/g and thickness was 3 ㎜. Effective size and uniform coefficient of the sand medium was 0.31 ㎜ and 2.0 respectively. Initial filtration rate was 0.167 m/hr and the raw water turbidity and pH were in the range of 1.5-2.0 NTU, and 7.0-7.7, respectively. The particle removal efficiency of small than 2 ㎛ showed 86, 78% and greater than 3 ㎛ showed 96, 95% in the slow sand filter A and B(ACF), respectively. NPOC removed within upper 50 ㎜ depth and Schmutzdecke in slow sand filter B(ACF). Therefore, amended slow sand filter with non-woven fabric could reduce filter ripening time.