신축학교 실내공기질이 초등학생들의 인지기능에 미치는 영향

김태섭,김선주,박시영,전만중,김규태,김창윤,정종학,백성옥,사공준 대한산업의학회 2007 대한직업환경의학회지 Vol.19 No.1

목적: 신축초등학교와 대조학교를 선정하여 교실 내 포름알데히드와 TVOCs를 측정하고 컴퓨터 신경행동검사를 이용하여 실내공기 오염물질이 학생들의 인지기능에 미치는 영향을 평가하였다. 방법: 신축초등학교 5학년 71명을 실내공기 오염물질 노출군으로 하고, 개교한지 12년째인 대구시의 일개 초등학교 5학년 2학급 63명을 대조군으로 하여 실내공기 오염물질농도 측정 및 컴퓨터 신경행동검사를 실시하였다. 결과: 신축학교에서 의도적으로 창문을 개방한 학급에서 1교시 포름알데히드 농도는 34.6 ㎍/㎥, 4교시에는 27.3 ㎍/㎥, 창문을 개방하지 않은 학급에서 1교시 80.2 ㎍/㎥, 4교시 127.1 ㎍/㎥, 대조학교에서는 2학급 각각 1교시에 12.6 ㎍/㎥, 7.5 ㎍/㎥, 4교시에 19.8 ㎍/㎥, 25.2 ㎍/㎥였다. TVOCs의 경우 신축학교의 의도적으로 창문을 개방한 학급에서 1교시에 농도는 487.2 ㎍/㎥, 4교시에 428.2 ㎍/㎥, 창문을 개방하지 않은 학급에서 1 교시에 농도는 1,283.5 ㎍/㎥, 4교시에 1,715.4 ㎍/㎥, 대조학교의 경우 2학급에서 각각 1교시에 농도는 240.9 ㎍/㎥, 150.8 ㎍/㎥, 4교시에 농도는 371.9 ㎍/㎥, 448.0 ㎍/㎥였다. 부호숫자 짝짓기의 평균반응시간은 대조학급이 1교시에 2,585 msec에서 4교시에 2,459 msec으로 감소한 반면 신축학교의 창문을 의도적으로 개방한 학급은 2,343 msec에서 2,510 msec으로, 평소대로 수업한 학급은 2,340 msec에서 2,563 msec으로 반응시간이 각각 167 msec, 223 msec 증가하였다. 1교시의 부호숫자 짝짓기 의 반응시간을 100%로 했을 때 창문을 의도적으로 개방 한 학급은 4교시에 5.9% 증가하였고(p<0.01), 평소대로 수업한 학급은8.3% 증가하였다(p<0.01). 반면에 대조학급은 4교시에 5.0% 감소하였다(p<0.01). 결론: 향후 학교의 실내공기질의 안전성 평가는 샘플링 된 공기의 오염수준의 측정뿐만 아니라 학생들의 건강영향도 함께 고려되는 것이 바람직할 것이다. Objectives: Most studies on the indoor air quality of newly built schools have focused only on the number of schools exceeding a standard or on subjective symptoms, such as sneezing, irritated eyes and an irritated nose. However, there has been no report on how poor indoor air quality affects children's academic performance. This study evaluated the effects of indoor air quality on the neurobehavioral performance of elementary school children. Methods: This study measured the indoor air pollutants and compared children's performance, using a computerized neurobehavioral test, between a newly built and a 12-year-old school. In addition, a questionnaire was administered regarding the indoor air quality related symptoms of children in a newly built and a 12-year-old school. Results: In the newly built school, the formaldehyde levels in the 1^(st) and 4^(th) classes with an open window were 34.6 and 27.3 μg/㎥, respectively. The levels in the 1^(st) and 4^(th) classes with the window closed were 80.2 and 127.1 μg/㎥, respectively. In the 12-year-old school, the formaldehyde levels in 1^(st) and 4^(th) class with open and closed window were 12.6 and 7.5 μg/㎥, and 19.8 and 25.2 μg/㎥, respectively. With respect to total volatile organic compounds, the levels in the 1^(st) and 4^(th) classes with the window open in the newly built school were 87.2 and 428.2 μg/㎥, respectively. In the 1^(st) and 4^(th) classes with the window closed, the total volatile organic compounds were 1,283.5 and 1,715.4 μg/㎥, respectively. In the 12-year-old school, the total volatile organic compounds were 240.9 and 150.8 μg/㎥, and 371.9 and 448.0 μg/㎥ in the 1^(st) and 4^(th) classes, respectively. In the case of a newly built school, the performance of the students in the neurobehavioral test in the 4^(th) class with the window closed was 8.3% lower than for those in the 1^(st) class with the window closed, but was only 5.9% lower when the windows were open. There was a statistical significant difference in the total numbers of symptoms between the two schools. Conclusions: These results suggest a proper evaluation of the indoor air quality within schools is required into both the level of contamination and the health effects of these contaminants toward children.

보성산 유기농 녹차의 품질에 따른 카테킨 함량과 항산화능 비교 분석

박경련(Kyung Ryun Park),이상길(Sang Gil Lee),남태규(Tae Gyu Nam),김영준(Young Jun Kim),김영록(Young-Rok Kim),김대옥(Dae-Ok Kim) 한국식품과학회 2009 한국식품과학회지 Vol.41 No.1

유기농 녹차의 등급별 총페놀 함량과 항산화능은 각 추출 용매에 따른 수율을 확인하였을 때 물 추출에 비하여 수용성 유기용매의 추출 수율이 유의적으로 높았다. 유기용매를 이용한 추출수율은 물을 이용할 때 보다 총페놀 함량은 1.5에서 3.2배, 항산화능은 1.8에서 3.8배 정도 높게 나타났다. HPLC 분석을 통하여 총페놀 함량과 항산화능의 상관관계를 비교 시 총페놀 함량이 증가함에 따라 항산화능이 1차 선형관계로 증가하는 경향을 보였다. HPLC분석을 통하여 유기농 녹차에 함유되어 있는 다양한 카테킨의 함량이 채엽시기에 따라 변화가 나타났다. 유기농 녹차의 카테킨 성분 중 가장 많이 존재하는 EGCG가 건조중량당 5.8-7.7%의 함량을 보였고, caffeine은 1.7-2.9%의 함량을 보였다. 유기농 녹차의 카테킨 함량은 일반적으로 채엽 시기가 늦어짐에 따라서 점차 감소하였다. 유기농 녹차의 등급에 따른 항산화능은 최상급인 우전에서 가장 높았으며 최하등급인 엽차에서 가장 낮게 나타났다. HPLC 분석에 의한 유기농 녹차의 등급에 따른 총 카테킨 함량(㎎/g)은 우전(155.4), 세작(147.7), 중작(143.2), 엽차(135.1), 대작(130.5)의 순서로 감소하였다. 이를 통해 녹차의 채엽 시기가 유기농 녹차의 카테킨 성분 및 항산화능에도 영향을 미치는 것을 확인하였다. 전반적으로 상급의 유기농 녹차 일수록 총페놀 및 카테킨 함량이 많으며 또한 더 높은 항산화능을 가지는 것으로 나타났다. The objective of this study was to evaluate the effect of various solvents on extraction of bioactive phenolics and to analyze the antioxidant capacity and contents of individual catechins in various grades of green teas organically grown in Boseong, Korea. The organic green teas, based on their harvest seasons, were categorized into five grades such as Woo-Jeon, Se-Jak, Jung-Jak, Dae-Jak, and coarse tea. Solvents used to extract phenolics from these teas included water at 23℃ and 70℃ as well as 80% (v/v) aqueous methanol and ethanol. In general, aqueous organic solvents of methanol and ethanol led to higher extraction yields of phenolics than water at 23℃ and 70℃. Total phenolics and antioxidant capacity of the teas extracted with the aqueous organic solvents were approximately 1.5 to 3.2 and 1.8 to 3.8 times higher than those with water at 23℃ and 70℃, respectively. Coarse tea, the lowest grade of green tea, showed approximately 30-60% lower total phenolics and antioxidant capacity compared with the higher grade ones. Reversed-phase HPLC analysis was performed quantitatively to identify individual catechins, gallic acid, and caffeine in teas extracted with 80% (v/v) aqueous methanol. Based on their dry weights, the organic green teas contained about 1.7 to 2.9% of caffeine. Content (㎎/g dry weight) of tea catechins decreased in the following order: Woo-Jeon (155.4) > Se-Jak (147.7) > Jung-Jak (143.2) > coarse tea (135.1) > Dae-Jak (130.5). (-)-Epigall℃atechin gallate was the most abundant among the catechins analyzed. The highest grade of green tea, Woo-Jeon, had the highest amount of (-)-epigall℃atechin gallate at 77.4 ㎎/g dry weight. Overall, the higher grade of organic green teas tended to have the higher level of antioxidant capacity and catechins.

산으로 개질된 활성탄의 메틸 메르캅탄 흡착특성

김대중,김상채,서성규 國立麗水大學校 環境問題硏究所 2004 環境硏究論文集 Vol.6 No.-

Adsorption characteristics of methyl mercaptan on virgin activated carbon(VAC) and modified activated carbons with acidic chemicals have been investigated in the present work. CAC, NAC, AAC and SAC were activated carbons modified with HCl, HNO₃, CH₃COOH and H₂SO₄, respectively. The pore structures and surface characteristics of virgin activated carbon and modified activated carbons were evaluated using nitrogen isotherm, EA, pH of carbon surface and acid value from Boehm titration. respectively. The modification of activated carbon with acidic chemicals resulted in decrease in BET surface area, micropore volume and surface pH, but an increase in acid value. In case of adsorption of methyl mercaptan. The order of the adsorption capacity of activated carbons was NAC>AAC>SAC>CAC>VAC. and in agreement with that of acid value of activated carbons, whereas in disagreement with that of micropore volume of activated carbons. It appeared that chemical adsorption played an important role in methyl mercaptan on modified activated carbons with acidic chemicals compared to virgin activated carbon. These results suggest that the adsorption of methyl mercaptan depends on the surface chemistry rather than the pore structure in modified activated carbons.

비소(Arsenic)에 의한 토양 오염과 복원기술

김대연,김정규 고려대학교 2004 생명자원연구 Vol.12 No.-

淨水슬러지의 固化處理에 關한 硏究

김대현,김문규,임성진 동의공업대학 2000 論文集 Vol.26 No.1

The purpose of this study is to determine the possibility of using as a fill material and cover soil, hardened up to a specific age by making a dosing such as slaked lime, bentonite into the sludge generated during waterworks treatment process with existing treatment system of a ocean dumping. For these reasons, this study carried out a basic physical property test, consolidation test, unconfined compression strength test, extraction test on heavy metals, X-ray diffraction analyzer, scanning electron microscope to determine a characteristic of modified waterworks sludge. In this case that waterworks sludge was modified by being mixed with slaked lime accounting for 10% of its total amount at the age of twenty eight day, the compression strength of the sludge was developed 1.0kgf/㎠ or over. This indicated that the sludge could be used as fill material and cover soil. The extraction test on waterworks sludge modified by slaked lime showed the below of KSP, TCLP standard. Estimation of coefficient of permeability as consolidation test showed less considerably in comparison with reported coefficient of permeability at the landfill site in Seoul Metropolitan area. For this reason, it was found that modified waterworks sludge could be used as fill material and cover soil. Accordingly if waterworks sludge was reused by hardening process, showing a more effecting in terms of economy, environment.

제품보호용 포장재 개발

김정필,강재현,박대연,유성구,서길수 영남대학교 공업기술연구소 2000 工業技術硏究所論文集 Vol.28 No.1

The environment to which a packaged-product is exposed, during handling and transportation, very often includes temporary storage. In the interest of conserving warehouse cube, packaged-products are stacked upon one another to a height which far exceeds that possible in a railcar, truck-trailer, aircraft or other conveyance. the hight to which the height to which a packaged-product may be stacked will vary depending upon the warehouse ceiling height-seldom over twenty feet. This procedure for expirimental covers testing of packaged-products weighing under 100 pounds when prepared for shipment. The BASIC requirements of this procedure consist of vibration and drop tests-which must be performed in that sequence.

원발성 두개골내 수막종 : 1예 보고 A Case Report

김대호,홍현숙,조준희,박재성,박성진,차장규,백상현,이혜경 순천향의학연구소 2004 Journal of Soonchunhyang Medical Science Vol.10 No.2

Primary intraosseous meningioma of skull is rare, and often confused with a primary bone tumor. We report a case of a 71 years old female patient with an intraosseous calvarial meningioma of frontal bone presenting as a solitary osteolytic skull lesion. Plain skull radiograph, CT and MR images show sharply marginated expansile bony lesion in frontal skull vault, and a small well enhanced soft tissue mass within bone. The mass is extracranially protruded to scalp, and is partially attached to the underlying dura. Outer and inner table of skull vault is slightly bulged out, suggesting intradiploic origin of the tumor. The tumor was treated with surgical excision and cranioplasty. Histological examination revealed fibrous meningioma.

문학 텍스트의 소통 구조 : 구보계 소설을 중심으로

김용성,이대규 全北大學校 敎育大學院 1997 敎育論叢 Vol.17 No.-

This thesis aims at clarfying communicative structure of literary text. In this paper, I focus on the 'GUBO' texts. According to the reception theory, the substance of literature is not only the printed text but also mutual action between writer and the readers. The 'text' is newly produced as a 'work' by the readers. Reception theory base on horizon of expectation for readers's understanding and appreciation of the literary text. Concreation of text is based on reader's horizon of expectation. The structure of reception is complex. Reception text is the result that interaction of horizons. Reading act needs the transmission of horizon, reconstruction of horizon, conversion of horizon(Horizontwandel), fusion of horizon(Verschmelzung der Horizont). From that point of view, experiential character of literature is thought be important. Now, the reader must set up stratage of communication and schema.

벽체에 작용하는 토압에 관한 모형실험

김문규,김대현 동의공업대학 2000 論文集 Vol.26 No.1

The model experiments were carried out to observe the variation of lateral earth pressure acting on the wall as vary the constraint of retaining wall, geometry of wall, and backfill width. For the experiments, a soil-box, model wall, and a rainer were designed and manufactured. The experiments were carried out with two different types of constraint on wall movement: i.e. first with completely fixed wall and second with movable wall depending on soil pressure. The measured lateral earth pressure was compared with that by an extended silo and wedge theories. The test results are summarized as follows: The measured lateral earth pressure approached to that from the extended silo theory as a narrower backfill width was used. Both experimental and theoretical results showed a good coincidence when the backfill width is Bc tan(45 -?? DS/2)H. But much deviated from that by an extended wedge theory. (원문을 참조하세요)

운동 강도의 차이가 흰쥐의 혈액 성분과 적혈구의 형태에 미치는 영향

김부환,김종오,지용석,최대원,윤진환,정일규,김영욱,오봉석 한국스포츠리서치 2004 한국 스포츠 리서치 Vol.15 No.4

This study was to investigate the effects on hematological indices and heinz body formation in various intensity, Male Sprague-Dawley rats were randomly divided into the control group, the low-intensity exercise group, nigh-intensity exercise group (n=7 in each group). Animals of the low-intensity exercise groups were put on exercise 30 min per 1 day, 5 days per week for 6-weeks. Animals of the high-intensity exercise groups were put on exercise 120 min per 1 day, 5 days per week for 6-weeks. Red blood cell count (RBC), hemoglobin (Hgb), hematocrit (Hct), mean ceil volume (MCV), mean hemoglobin corpuscular (MCH), mean hemoglobin corpuscular concentration (MCHC) were analyzed in automated hematology analyzer (ABX Hematology MICROS 60) from 10㎕ of whole blood. Erythrocyte morphology were evaluated in super vital (Brilliant cresyl blue stain) stained blood films. In the present results, Hg, MCHC in the high-intensity exercise group was significantly decreased compared with the different exercise intensity and the control group. MCV in the high-intensity exercise group was significantly increased compared with the different exercise intensity end the control group. Heinz body formation in the high-intensity exercise group was significantly increased compared with the different exercise intensity and the control group. In the present study, it can be suggested that intensity of exercise can influence hematological variables and heinz body formation. These findings suggest that high intensity exercise induces oxidative damage to erythrocyte.