망간페라이트 나노 분말의 수계분산거동 및 특성

배동식,김은정,한경섭 국립7개대학공동논문집간행위원회 2004 공업기술연구 Vol.4 No.-

Dispersion stability of nanosized MnFe₂O₄ powders which was produced by glycothermal process were studied in aqueous suspension using ESA(Eletrokinetic Sonic Amplitude). The average particle size of the synthesized MnFe₂O₄was about 30±10nm. The dispersion and rheological behavior of MnFe₂O₄nanoparticles aqueous suspension was investigated using MnFe₂O₄as a disperse agent. The colloidal stability of nanosized MnFe₂O₄aqueous suspensions at different pH values has been investigated by means of zeta potential, sedimentation, average particle size and microstructure of green body. The isoelectric point of MnFe₂O₄powders is at pH around 5.5 and the value of zeta potential is at its maximum near pH 11.

브롬화 및 염화아실들의 친핵성 치환반응 : 지방족 할로겐화 아실의 페놀화 반응 메커니즘(1)

金昌培,鄭泰泳,姜京熙 단국대학교 1978 論文集 Vol.12 No.-

Phenolysis rates of chloroacetyl, acetyl, propanoyl, isobutyryl and pivaloyl chlorides were measured in acetonitrile using three different weak nucleophiles, phenol, p-nitrphenol, and p-methoxyphenol. Result from phenolysis of acetyl chloride revealed that (1) the reaction was approximately second order (2) the rate was fastest with p-methoxyphenol, the strongest nucleophile of the three when phenol concentration was below 0.2M. However, at higher concentration phenolysis rates were in the order of p-Methoxyphenol>p-Nitrophenol>Phenol The varying order in reactivity as a function of phenol concentration was explained tentatively due to medium effect. p-Methoxyphenolysis was conducted using five different aliphatic acyl chloride, and their reactivity changes ClCH_2COCl<CH_3COCl≥CH_3CH_2COCl>CH_3)_2CHCOCl>CH_3)_3CCOCl Intervention of acylium lon-pair was considered to be the best reaction scheme, while neutral structure was important for chloroacetyl chloride.

초·중등 및 대학교재 중 물질특성에 대한 연계성 연구

李京玧,文正大,文星培 釜山大學校 師範大學 1998 교사교육연구 Vol.36 No.-

Material Characteristics contents in the chemistry textbooks from elementary school to college were investigated to consider the effectiveness of curricular articulation. For this purpose, the eleven subjects of chemistry contents were selected from chemistry textbooks, and the learning purpose and contents were analyzed through the classification rules. The results of analysis showed that total articulation were relatively effective. But the gaps partly appeared in case of comparing with the level of intellectural development of student. On the based of this results a new concept diagrams were proposed through the structure diagrams considered both macro and micro aspect. To develop the curricular articulation between the school units it is important that textbooks should be with the consistent plan after the discussion with the actual teachers of the school units.

재발성 다발연골염 1례

이배혁,고의경,왕수건,전경명 釜算慶南耳鼻咽喉科學會 1994 임상이비인후과 Vol.5 No.1

일부 수영장 욕수 및 이용객 urine내 Trihalomethane 농도

문경환,손종렬,김영환,변상훈,배은상 高麗大學校 倂設 保健大學 保健科學硏究所 1998 保健科學論集 Vol.24 No.1

Chlorination of swimming pool water leads to many chlorinated products. The most frequent derivative is trihalomethane(THMs). This study was performed to investigate the distribution of THMs in swimming pool water and ambient air, and to determine whether THMs concentrations in swimmers' urine Were influenced significantly after swimming. Water samples were collected from 22 indoor and outdoor swimming pools. Concentrations of THMs in swimmers' urine determined before and after their stay in swimming pools. Results of the study as follows. 1. The concentrations of THMs in the indoor swimming pools water(41.85±73.22㎍/L) were significantly increased(p<0.05) in comparison with that of outdoor swimming pools (10.15±15.45㎍/L). The average concentration of THMs in indoor ambient was 51.2㎍/㎥, which was significantly higher than that of air quality. 2. As a results of regression analysis between THMs and water quality factors, the concentration of pH, residual chlorine and KMnO₄ consumption were highly correlated in indoor swimming pools. 3. In almost all cases, only CHCl₃ was quantifiable. The proportions of THMs in urine correlated roughly with those in water and the secretion of THMs increased significantly after swimming in the pools.

빠른 보행을 위한 이족 로봇의 설계

강민구,배지훈,박경용,김갑일 명지대학교 산업기술연구소 2001 産業技術硏究所論文集 Vol.20 No.-

In this paper, a biped robot is designed and implemented, and walking tests are performed using a fast walking model. In order to embody the human joint structure, designed biped robot has each two degree of freedom attached to the pelvic, knee, and ankle . Using two motors for each knee makes it possible to have the same walking as human walking and fast walking. Also in joint controller, PID control algorithm may causes variation to the robot, which make the system unstable. Therefore, a PD controller is used to limit the vibrations as much as possible allowing steady state error to a certain extent.

病院 地下空間內의 空氣中 微生物分布에 관한 硏究

박천제,배병훈,고경숙,김춘희,임경택 동아대학교 환경문제연구소 1998 硏究報告 Vol.21 No.1

This study was carried out to investigate the distribution and concentration of microorganism by the method of the air contamination using RCS air sampler in underground linac room of two general hospital located in Pusan. The places of air sampling were 4 different spot in two each hopital. Therefore, total 8 places were sampled from June 30, 1996 to May30, 1997. The results obtained were as follows 1. In a agar strip GK-A media for total count of microbial particles, it was estimated to be 76 CFU/ft^(3) in ICR room, and the consulting room was 53 CFU/ft^(3), lobby was XI CFU/ft^(3), linac room was 35 CFU/ft^(3), in the M hospital, respectively. The distribution of organism in the air of M hospital were shown gram positive cocci 72%, gram negative bacilli 15%, gram positive bacilli 6.1%, fungi 6.1%, respectively . On the other hand, in P hospital, it was obtained to be ICR room 74 CFU/ft^(3), lobby- 45 CFU/ft^(3), consulting room 34 CFU/ft^(3), linac room 31 CFU/ft^(3), respectively. The distribution and concentration of microorganism in the air were detected gram positive cocci 75%, fungi 10.3%, gram negative bacilli 8.7%, gram positive bacilli 6.0%. respectively. The results were recognized to be a low frequency in the linac room. 2. In agar strip S media for total counts of M hospital, ICR room was shown the highest organism with 32 CFU/ft^(3), but the lowest organism was detected linac room with 20 CFU/ft^(3). Also, the case of P hospital was estimated high 43 CFU/ft^(3) at ICR room, low organism was shown at linac 17 CFU/ft^(3) Test of coagulase were recognized to be a negative Staphylococci 68.3% in M hospital, 60.7% in P hospital. Coagulase positive cocci was estimated to be 31.7% in M hospital, 39.3% in P hospital. 3. In agar strip C media for coliform bacteria, colony counts at ICR room 10 CFU/ft^(3), consulting room 7 CFU/ft^(3), linac room 6 CFU/ft^(3), lobby 4 CFU/ft^(3) in M hospital, respectively. On the other hand, in P hospital were shown ICR room and main lobby 7 CFU/ft^(3), consulting room 5 CFU/ft^(3), linac room 4 CFU/ft^(3), respectively.

비신경교종 1례

김재욱,이배혁,오일준,전경명 釜算慶南耳鼻咽喉科學會 1993 임상이비인후과 Vol.4 No.2

일부 반면형 호흡기보호구 착용시 안면 크기 및 성별에 따른 밀착도 변화

변상훈,문경환,손종렬,김영환,배은상 高麗大學校 倂設 保健大學 保健科學硏究所 2000 保健科學論集 Vol.26 No.1

The fit of a respirator to the Face of an individual can be determined by a qualitative fit test((QLFT) or a quantitative fit test (QNFT). A quantitative fit test, was performed to evaluate leak values with Mask Fitting Tester. Two brands of half face respirators(M,S) were tested on 110 wearers on time. This study was investigated how the fit factors resulting from a quantiative fit test (QNFT) depend on the movements in the six test exersize regimes. Fit factor were low when face lengthes were higher or lower than average values. In this research we studies the koean's face length and compared the result with one of the American and the Japanese after wearing the Half-Mask Respirators, some changes in their leak were found and the results were as follows. 1. Although most testee were young, the Korean's face length were similar to the American while the male face length were similar to the Japanese. 2. For men, thier face length has been longer about by 1㎝ but mouth's length shorter about by 0.3㎝ than 10 years ago. 3. If the face length were not normality (such as higher or lower) leak degree was too high to be appropriate for the Respirator. 4. Both M and S company their respirators showed that the male leak degree was two times lower than female. Therefore, the resporators in the current market were believed to forcus it's target for male consumers. 5. The result of QLFT in a male showed that pass% of M was 20% higher than S. 6. In the result of QLFT, pass% of S was 25% highr than M in a female 7. These results(5&6) showed that S were more suitable in a female and M were more suitable in a male

加耶聯盟國形成에 關한 經濟史的 考察 : 特히 洛東江系 下流 流域의 物産을 中心으로

許南壁,文暻鉉,徐永培 慶尙大學校 1977 論文集 Vol.16 No.2

We aim in this paper at discussing the economic foundations which formed driving forces for bulding up of the triabl cutires "Byon-han", alias "Kaya" alliance. With the term "Kaya" alliance we refer to the ancient allied countried of Dae-Kaya(whose capital was Koryong), Songsan-Kaya(Songju), Bihwa-Kaya(Changnyong), so-Kaya(Kosong), Kumkwan-Kaya(Kimhae), Koryong-Kaya(Song-chang), and Alla-Kaya (Haman). For a historical study on the formation of these powerful tribal countries, we would like to point out two major factors" production of iron in the mountainous districts, and that of rice in the alluvial plains along Nakdong River. For the first factor we would say that in ancient times iron was so important material for farming tools, defensive weapons and horsehoes that aboundant iron production had a direct effect on the national power of these agricultural countries. Secondly, rice also, as main provisions, was a principal barometer of their national power, because abundant grain production could increse their population and be used as their military provisions. Moreover, marine resources in the South Sea such as salt, seaweeds and fishes added something more to what was already abunant. These two major factors as driving forces played the most important part in the formation of "Kaya" countries, for their locatioinal condition was favorable enough to possess both elements. They were located in the fertile alluvial plains alog Nakdong River, the Nile of Korea, and their territories formed prominent granaries of Korea. Hence the abundant wealth of agricultural products formed groundwork for the formation of "Kaya" allianace.