치질에 흡수된 불소가 미세경도와 불소함량에 미치는 영향

이수종,정진호,반일환 조선대학교 구강생물학연구소 2003 Oral Biology Research (Oral Biol Res) Vol.27 No.1

The Purpose of this study was to evaluate the influence of fluoride uptake on microhardness and fluoride contents of tooth structure, Forty extracted human teeth were used, which were prepared proximal cavities. Experimental teeth were divided into five groups. Group 1: Prime & Bond NT and 2100 : Group 2 : Prime & Bond NT and F2000 : Group 3 : Scotchbond Multi-Purpose and 2100 : Group 4 : Scothcbond Multi-purpose and F2000 : Group 5 : Fuji Ⅱ LC. The cavities were filled with dentin adhesives and restorative materials. Teeth were coated 2 times with nail varnish. and immersed in a polypropylene tube. Tubes were stored in water bath at 37±0.5℃. After four weeks, the tooth was bisected longitudinally and the microhardness of the dentin and enamel were determined by indentation (at 30.100㎛ depth). The other halves were analyzed for fluoride by an EPMA-WDX device (at30, 100, 200㎛ depth). The results were as follows : 1. There was no correlation between the microhardness and amount of uptaken fluoride in the all groups. 2. There was no significant statistical difference in the amount of uptaken fluoride of the all groups in enamel without regard for groups and depth(p>0.05). 3. In the Group 2 and 5, EPMA-WDX result showed higher fluoride uptake of the. each depths in dentin(p<0.05). 4. At 30㎛ depth in dentin, EPMA-WDX result showed that group 2 had higher fluoride uptake than group 1 and 3 and group 5 had than the other groups. In conclusion, fluoride uptake increased by fluoride releasing materials. But, it was influenced by dentin bonding agents and surface conditions. Therefore, further study about relation between dentin bonding agent, surface coating, and fluoride uptake is necessary.

계류기구로 관측한 대구시 야간 안정층 특성에 관한 사례연구

김희종,윤일희,권병혁,허만천 한국환경과학회 2002 한국환경과학회지 Vol.11 No.3

Using measured data at Daegu by tethersonde for the period or 1984~1987, we have investigated the lower atmospheric boundary layer structure including relationships between inversion layer and meteorological factor(wind and temperature), and the inversion strength and inversion height. The inversion layer was defined from the vertical temperature profile and its strength was analyzed with the wind shear as well as the vertical temperature gradient. From October to January, measured inversion layer isn't destroyed, however, in June, after sun rise, it is destroyed by surface heating and mixed layer is developed from surface. According to pasquill stability classes, the moderately stable cases dominated. It's the larger vertical temperature gradient, the lower SBL height. We have introduced B(bulk turbulence scale) which indicated SBL height. It's larger B, the higher SBL height and vice versa. It was noted that the bulk turbulence scale (B) is appropriated to determine the stable boundary layer height.

La, Mg 이온교환 ZSM-5 촉매의 제조와 촉매 산강도에 따른 MTO 반응 활성의 검토

김한일,황종현,정태환,정석진 경희대학교 산학협력기술연구원 1997 산학협력기술연구논문집 Vol.3 No.-

The MTO(methanol to olefin) process that aims at the production of olefins from methanol has attracted research interest because of its possiblity as another source of raw material in petrochemical industries. However its reaction path is not only ceased at the point of olefin production but also much amount of by products such as paraffins and aromatics that accelerate carbon deposit are produced. Thus the catalyst deactivation is rapidly progressed. In order to maximize the selectivity from methanol to olefin, alkylation and aromatization should be excluded from reaction path through catalyst and process variables. In this viewpoint, as a solution of the former problem, various metals were substituted on HZSM-5 which is used in commercial MTO process. With NH_3 TPD and activity test, the correlation between reaction products and possibility in control of Bro¨nsted acid site which is reported as the reaction active site was investigated. In this study, ethylene and propylene are the target products because of their wide applicating field.

腰痛을 同伴한 足下垂 患者 1例에 대한 臨床報告

김종국,유호상,윤일지,오민석 대전대학교 한방병원 2002 惠和醫學 Vol.11 No.1

After treating a patient suffering from foot drop which is caused by peroneal nerve paralysis, some result are gained as follows. Patient, 73 years old women, was treated from June 7 to July 15 in oriental hospital of Daejeon University. This disease is foot drop is caused by peroneal nerve paralysis which paralyze tibialis anterior muscle, fibula muscle, and extensor musculi of foot. Peroneal nerve contains nerve root of L4, L5, S1 and S2. Foot drop correspond to flaccidity-syndrome(^ISE). Flaccidity-syndrome(?/症) means that the muscle and the pulse of body is relaxed and the limbs become week and the man have a difficulty to move for oneself. The cause of this case on oriental medicine is Yin-deficiency of liver and kidney. Treatments which was based on cause of oriental medicine - herb medication, acupuncture treatment, electronic acupuncture treatment and moxibustion - have a good effect to patient.

충주시에서의 LPG 탱크로리 수송중 위험성 평가에 관한 연구

白種培,李聖一 忠州大學校 1997 한국교통대학교 논문집 Vol.32 No.1

The demand of LPG and LNG will increase continuously due to high calories, clearness, and convenience for usage. These gases are used widely for power plants, industrial plants, and domestic fuel. But accidents related with gas are increasing in proportion to the increment of gas usage. Especially, LPG has high ignitability due to a weak dispersion to air and an accumulation at low place because LPG is heavier than air. There are many hazards during transportation as well as production, storage, and usage of LPG. Commonly, tanklorry is used for inland transportation of LPG. If tanklorry were to raise leakage incidents and then LPG is released during transportation, it will have serious effects on the environment as well as human damage to surrounding area. In this study, therefore, hazards which cause LPG of tanklorry to leak during transportation were identified and the risk of LPG transportation was assessed quantitatively. Accordingly, the result of this study might be a useful measure for predicting damage and preparing safe transportation strategies of LPG tanklorry.

대두유의 자동산화 및 가열산화에 미치는 정향추출물의 항산화 효과

박상일,손종연 한국조리과학회 2004 한국식품조리과학회지 Vol.20 No.1

This study was conducted to investigate the antioxidant activities of clove extracts in water, methanol and ether. The clove extracts, BHA and α-tocopherol were added to each oil at a level of 200ppm. The activities of the substrate oils and controls were tested under autoxidation and thermal oxidation conditions. The degree of the effects of the antioxidant activities under autoxidation condition were in the following order: ether extract〉methanol extract〉BHA〉α-tocopherol〉water extract=control group. The induction periods of the control, water, methanol and ether extracts, and BHA and α-tocopherol were 9.5, 9.6, 10.7, 11.8, 10.4 and 9.7 days, respectively. Under thermal oxidation condition, the methanol extract showed stronger antioxidant activity than those of the water and ether extracts. The antioxidant activity of the methanol extract was attributed to α-tocopherol and BHA.

수확후 채소류에 발생하는 진균독소의 탐색과 방제(Ⅱ) 이병된 양념 채소류(양파, 마늘, 고추)에서 주요 진균독소 검출

정일민,주호종,심성철,백수봉,유승헌 충남대학교 생물공학연구소 1999 생물공학연구지 Vol.7 No.-

수확후 Alternaria, Penicillium 및 Fusarium에 이병된 고추, 양파, 마늘을 HPLC로 주요독소들을 검정한 결과 고추에서 Alternaria 독소의 AOH(alternariol)는 소량∼440㎍/g 및 ALT(altenuene)는 소량∼103㎍/g, TeA(tenuagonic acid)는 249∼342㎍/g 및 AME(alternariol monomethyl ether)는 206∼294㎍/g이 검출되었고 양파, 마늘에서 Penicillium 독소의 citrinin이 2.8∼18.4㎍/g, penicillin-G는 0∼439.0㎍/g, penicillic acid는 0∼10.2㎍/g 및 patulin은 0∼7.0㎍/g 검출되었다. 그리고 양파, 마늘에서 Fusarium 독소로는 fusaric acid가 0∼553.6㎍/g 검출되었을 뿐 deoxynivalenol과 nivalenol은 검출되지 않았다. The major mycotoxins were detected from peppers, onions and garlics infected postharvest pathogens, Alternaria, Penicillium and Fusarium. Analyses of the major mycotoxins were conducted using HPLC. Detected Alternaria mycotoxins per gram of infected postharvest peppers were alternariol (AOH) with amount ranged from small quantity to 440 ㎍/g, altenuene (ALT) with amount ranged from small quantity to 103 ㎍/g, tenuagonic acid (TeA) with amount ranged from 249 to 342 ㎍/g and alternariol monomethyl ether (AME) with amount ranged from 206 to 294 ㎍/g. Penicillium toxins per gram of infected postharvest onions and garlics were citrinin with amount ranged from 2.8 to 18.4 ㎍/g, penicillun-G with amount ranged from no detection to 439.0 ㎍/g, penicillic acid with amount ranged from no detection to small quantity and patulin with amount ranged from no detection to small quantity. Fusarium toxins per gram of infected postharvest onions and garlics were fusaric acid with amount ranged from no detection to 553.6 ㎍/g. However, deoxyrivalenol and nivalenol were not detected from onins and garlics infected by Fusarium.

현행 중학교 과학 실험·실습교육에 대한 교사들의 견해와 개선방안

이윤종,기우항,김영호,정원우,양승영,강용희,안병호,임성규,윤일희,김중욱,강동진 경북대학교 과학교육연구소 1996 科學敎育硏究誌 Vol.20 No.-

The status of facilities, management of the experiment, practices, and Science education teaching method in middle school have been investigated. The present status and reasonable management of middle school science education have been grasped from the questionaires. The results are as follows : The reasonable management for expeiments and practices of science education were scanty in the middle school around the urban and rural schools owing to the shortage of facilities and equipments, crowded class, excessive classes, work for teachers, excessive contents of present textbook and insufficience of administrative support etc. The current teaching method of middle school science has emphasized knowledge. This fact does not satisfy the objective of learning due to lack of teaching method. Desirable directions for the improvement of present status of middle school science education were proposed in this paper.

보직교사에 대한 역할기대와 역할수행 지각

신종국,한일조 금오공과대학교 2005 論文集 Vol.26 No.-

The study was attempted to analyse the teachers' perception of chief teachers' role expectation and role performance. A questionnaire asking teachers' thinking of chief teachers' role expectation and role performance was distributed over 320 high school teachers selected by stratified rancbm sampling throughout Gurni, Girnchon, and Sangju area of Gyeongbuk Province. Ordinary teachers tended to see chief teachers' role performance as 'so and so', responding positively to the questions of office and assistant work but negatively to the questions of lead/advice, mediation/arbitration, and human relationship work Teachers also expected high of chief teachers' role, especially in the field of mediation/arbitration. And generally ordinary teachers' role expectation of chief teachers was higher than their valuation of role performance, reaching the highest in mediation/arbitration.

Interleukin-1β에 의하여 치주인대세포에서 유리된 cytokine이 파골세포형성에 미치는 영향

이종갑,곽월아,유윤정,이승일,김태선 大韓小兒齒科學會 1996 大韓小兒齒科學會誌 Vol.23 No.1

Tooth movement is induced by bone remodeling during orthodontic treatment. Bone remodeling is regulated by various cytokines. Especially interleukin-1 (IL-1β), a cytokine present in periodontal ligaments of experimentally moved teeth, elicits bone resorption. In these processes, IL-1-induced bone resorption is mediated by interleukin-6 (IL-6) and granulocyte macrophage-colony stimulating fector (GM-CSF) secreted from osteoblasts. Periodontal ligament cells, which function as an anchorage for tooth, lie between alveolar bone and cementum. Therefore cytokines produced in the periodontal ligament (PDL) cells may also directly affect alveolar bone resorption in orthodontic tooth movement. Here I have examined whether PDL cells express IL-1β,interleukin-6 (IL-6) and granulocyte macrophage-colony stimulating factor (GM-CSF) mRNA and secrete those cytokines in response to IL-1β. Finally I have investigated whether IL-6 produced from PDL cells induces osteoclast formation in mouse bone marrow cell cultures. The expression of mRNA was estimated by polymerase chain reaction (PCR). The concentration of cytokines was quantified using enzyme linked immunosorbent method and the osteoclasts in bone marrow cultures were identified by tartrate resistant acid phosphatase (TRAP) stain. As results of these studies, IL-1βstimulated the expression of IL-1β, IL-6 and GM-CSF mRNA in PDL cells. 0.05 ng/ml IL-1βalso induced maximum production of Il-6 and GM-CSF in these cells. After an addition of IL-1β(0.05 ng/ml), IL-6 production increased from 2 hours to 8 hours and GM-CSF production also increased from 4 hours to 8 hours. IL-6 (100 ng/ml) increased the number of TRAP positive multinucleated cells in the presence of soluble interleukin-6 receptor (sIL-6R, 100 ng/ml). These results suggest that IL-1βmay stimulate alveolar bone resorption by inducing IL-6 and GM-CSF production in PDL cells which enhance osteoclast differentiation and IL-6 enhances osteoclast formation in the presence of sIL-6R. And this process by IL-1βmay be closely associated with alveolar bone resorption induced by orthodontic force.