• 대한화학회지
• /
• 제44권1호
• /
• pp.74-80
• /
• 2000

본 연구는 제 6차 교육과정에 의거하여 개정된 고등학교 화학 II 교과서 실험 중에서 염소의 제법과 성질 실험에 대한 비교 분석 및 개선에 목적을 두고 있다. 국내 9종 교과서에서 다루고 있는 염소 기체의 발생 실험을 수행하여 문제점을 발견하고 최적의 실험 방법을 제시한다. 염소 기체의 발생 실험에서 가장 큰 문제점은 인체에 해로운 염소 기체를 학생들이 흡임할 수 있다는 것이므로 염소 기체를 흡입하지 않고 안전하게 실험하는 것에 중점을 두었다. 실험실에서 간단하고 쉽게 관찰할 수 있는 염소 기체의 성질 확인 방법도 5가지로 정리해서 제시한다.

• 한국기계가공학회지
• /
• 제19권9호
• /
• pp.40-46
• /
• 2020

Inspection of vehicle systems is regularly performed by the state to ensure the emission status and the safety of vehicles. Thereby, the safety and quality of life can be improved by reducing green-house gases and fine dust, which are the main causes of vehicle defects and air pollution. This study analyzed the soot measuring probes used in the free acceleration mode method, at no-load condition, looking at the efficiency of a probe to measure soot emissions from diesel vehicles. In this study, a technique that can improve the inhalation efficiency of the probe over the (a) probes and the improved (b) probes was applied to probes (c). Probe (c) involves a structure designed close to the center of the circumference of the exhaust pipe. Results showed that the suction efficiency was improved by adding a variable center unit.

• 대한인간공학회지
• /
• 제24권4호
• /
• pp.47-53
• /
• 2005

This study aim to investigate the effects of supply of oxygen enhances cerebral activation through increased activation in the brain and using a 3 Tesla fMRI system. Five volunteers (right handed, average age of 21.3) were selected as subjects for this study. Oxygen supply equipment that provides 30% oxygen at a constant rate of 15L/min was given using face mask. A 3 Tesla fMRI system using the EPI BOLD technique, and three-pulse sequence technique get of the true axial planes scanned brain images. The author can get the perfusion images of the brain by oxygen inhalation with susceptibility contrast EPI sequence at the volunteers. Complex movement consisted of a finger task in which subjects flexed and extended all fingers repeatedly in union, without the fingers touching each other. Both task consisted of 96 phases including 6 activations and rests contents. Post-processing was done on MRDx software program by using cross-correlation method. The result shows that there was an improvement in performance and also increased activation in several areas in the oxygen method. These finding demonstrates that while performing cognitive tasks, oxygen administration was due to increase of cerebral activation.

• Korean Chemical Engineering Research
• /
• 제60권4호
• /
• pp.519-524
• /
• 2022

국내 건축물 마감재는 국토교통부 고시에 따라 KS F 2271 기준에 의해 평가되어지고 있으며, 이 실험은 실험동물을 사용하여 평가하고 있다. 본 연구에서는 가연성이 높은 유기물 단열재 EPS, 우레탄, 페놀폼에 대해 실험을 진행하였다. 이 3종의 단열재가 연소 시 발생되는 유해성 가스에 의한 실험용 쥐의 평균행동정지시간을 측정하여, 실험용 쥐의 행동정지에 대한 원인을 분석하고자 하였다. 실험용 쥐의 행동정지에 대한 원인분석방법으로는 FTIR 분석과 연기밀도실험을 진행하였고, 마우스의 행동정지 원인을 입자상물질에 의한 질식과 가스상물질에 의한 독성흡입으로 구분하여 실험결과를 분석하였다. 실험결과 우레탄이 가장 유해한 단열재로 평가되었으며, 가스유해성 실험결과에 대한 원인분석으로 FTIR분석과 연기밀도 실험을 진행한 결과, 독성흡입에 의한 영향보다 질식에 의한 실험용 쥐의 행동정지가 높은 것으로 나타났다. 본 연구는 유해성가스의 원인분석에 대한 기초연구로서, 독성의 근거를 마련하고 나아가 다양한 재료와 가스에 대한 분석을 통하여 보다 구체적인 독성평가의 기준이 마련될 수 있을 것으로 기대된다.

• The Korean Journal of Physiology
• /
• 제20권1호
• /
• pp.53-63
• /
• 1986

과산화수소$(H_2O_2)$가 급성 일산화탄소(CO)중독의 회복에 미치는 영향을 알아보기 위하여 가토를 1% Corktm에 30분간 노출시킨후 자연회복군, 100%산소 흡입군 및 $H_2O_2$관장군(10ml/kg의 0.5% $H_2O_2$용액을 2ml내외의 사람혈액과 함께 관장)으로 나누어, 회복기 15,30,60 및 90분에 동맥혈의 $pH,\;PCO_2,\;CO_2$ 및 HbCO 포화도를 측정하여 다음과 같은 결론을 얻었다. pH는 급성 CO중독시 3개군 모두에서 감소하였고, 회복기에는 서서히 증가하여 자연회복군과 100%산소 흡입군은 회복기 90분에 거의 회복되나, $H_2O_2$관장군에서는 pH의 회복이 다른군보다 늦었다. $PaCO_2$는 급성 Co중독시 3개군 모두에서 감소하였고, 회복기에는 서서히 증가하였으나, 자연회복군의 $PaCO_2$는 회복기 90분에 거의 회복하는데 반하여 100%산소흡입군과 $H_2O_2$관장군의 $PaCO_2$는 회복이 늦었고 회복기 90분에도 완전히 회복되지 못하였다. $PaO_2$는 급성 Co중독시 약간 감소하였다가 회복기에는 회복기 15분부터 급격히 증가하였고 회복기 90분까지 대조치보다 높은 $PaO_2$를 유지하였다. 회복기동안 $H_2O_2$관장군의 $PaO_2$는 $102{\sim}107mmhg$로 자연회복군보다 약 10 mmhg 높은 수준을 보였다. HbCO 포화도는 급성 CO중독시 $54{\sim}72%$까지 증가하였다. 회복기에는 $H_2O_2$관장군의 HbCO 포화도의 회복이 자연회복군이나 100%산소 흡입군보다 빨랐으며, 100%산소 흡입군은 회복기 30분에서 60분사이에 자연회복군보다 더 빠른 회복을 보였다. 이상의 결과에서 0.5% $H_2O_2$관장은 CO중독시 혈액의 산소분압을 어느정도 증가시킬 뿐 아니라 혈색소와 결합된 CO의 해리를 촉진시켜, 단독요법 또는 산소요법과 병행하여 사용할 때 급성CO중독에 효과적인 치료법이 될 수 있을 것으로 사료된다.

• 한국운동역학회지
• /
• 제25권2호
• /
• pp.199-206
• /
• 2015

Objective : The purpose of this study was to conduct a biomechanical analysis of a one-legged jump in a traditional Korean dance (Wae Bal Ddwigi) according to breathing method. Method : Participants for this study were 10 dancers with experience for at least 10 years in traditional Korean dance. Independent variables for this test were two different types of breathing methods. Dependent variables were ground reaction force and lower extremity kinematic variables. The jumping movement was divided into three separate stages, take off, flight, and landing. The subjects were asked a questionnaire regarding the degree of impact force and stability of landing posture after the experiment. The Kistler Force Plate (9281B, Switzerland) was used to measure ground reaction force. A digital camera was used to look into angles of each joint of the lower part of body. SPSS was used for statistical analysis via the dependent t-test(p<.05). Results : There were significant differences in jumping according to breathing method. The inhalation & exhalation method yielded significantly longer flight times combined with greater ground reaction force. The breath-holding method required more core flexion during landing, increasing movement at the hips and shoulders. Conclusion : Consequently, there was more flexion at the knee to compensate for this movement. As a result, landing time was significantly higher for breath-holding.

• Toxicological Research
• /
• 제21권2호
• /
• pp.141-150
• /
• 2005

1,3-Dichloro-2-propanol (1,3-DCP) is known as chloride chemicals and causes severe hepatotoxic agent. The Ito cells and Kupffer's cells of the liver in the 5 old F344 Rats were exposed to 1,3-DCP gas chamber for 6 hours/ a day, 5 days/ a week, and 13 weeks, in the 0, 5, 20, 80 ppm, respectively. After then the body weights, liver weights, and relative liver weight to body weight were measured, and the hepatic tissues were prepared by the routine and Immunostain method, and observed by the LM, and EM. In the results, there were severe body weight decrease (p<0.05) in the 80 ppm of the male and female rats. The relative liver weights to the body weight were increased relate with exposed 1,3-DCP concentration (P<0.001). Inflammatory cells, infiltration was observed at the perivascular area in the 20 ppm exposed group, and bilirubin pigment infiltration, bile duct hyperplasia, inflammation hepatocytic necrosis, fibrosis were observed in the 80 ppm exposure group. In the 80 ppm exposure group, disarrangement of the endothelial cells, erythrocytes and hepatic cell fragment in the Disse space and numerous migration macrophages were observed in the necrotic area by EM observation. In the immunostained hepatic tissues positive stained ED1 cells were extremely increased (P<0.05) in central vein area, but ED2 was weakly positive immunostained in the 80 ppm exposed group. Immunostained desmin was observed in the Ito cell. It was no difference in the low and medium exposed group but it was typical increase in the necrotic area. In conclusion, These results suggest that NOAEL of 1,3-DCP may be 5 ppm in rats and the Immunostained of desmin, ED1 and ED2 positive cells activated in the inflammatory liver were related to the exposure volume and density. The increase of the Ito cells were related to the severe phagocytosis of the Kupffer's cells.

• The Korean Journal of Physiology
• /
• 제8권1호
• /
• pp.39-43
• /
• 1974

정상가토(正常家兎)에 ether와 methoxyflurane으로서 흡입마취(吸入麻醉)시킨 후(後) 마취(麻醉)의 심도(深度)와 시간경과(時間經過)에 따른 각기혈당량(各其血糖量)을 측정(測定)하고 대조군(對照群)의 그것과 비교(比較)한 결과(結果) 다음의 결론(結論)을 얻었다. 1. 대조군(對照群)의 혈당량(血糖量)은 $112.04{\pm}9.88\;mg%$이었다. 2. Ether 마취군(麻醉群)에서, 경마취시(輕麻醉時) 혈당치(血糖値)는 $193.57{\pm}2.40$ mg%로서 증가(增加)하였다. 심마취즉후(深麻醉卽後)에는 혈당치(血糖値)가 $130.75{\pm}5.33mg%$로서 다시 저하(低下)되었다. 심마취시간(深麻醉時間)의 경과(經過)에 따라 혈당치(血糖値)는 계속 상승(上昇)하여 심마취(深麻醉) 120분(分)에서는 $188.61{\pm}12.33mg%$에 달(達) 하였다. 3. Methoxyflurane 마취군(麻醉群)에서는 ether 마취군(麻醉群)과 유사(類似)하게 혈당치(血糖値)의 증가양상상(增加樣狀相) 보여 주었고 methoxyflurane 경마취시(輕麻醉時)의 혈당치(血糖値)는 $186.89{\pm}10.90mg%$였다. 심마취즉후(深麻醉卽後)에는 $111.28{\pm}16.81mg%$로 저하(低下)되었다가 시간(時間)의 경과(經過)에 따라 상승(上昇)하여 120분(分)에서는 $208.98{\pm}7.52mg%$로서 상당히 상승(上昇)하였다. 4. 이상(以上)의 결과(結果)로서 ether와 methoxyflurane 마취시(麻醉時) 혈당치(血糖値)의 변동(變動)은 시간경과(時間經過)에 따라 유사(類似)한 결과(結果)를 얻었다.

• 한국환경보건학회지
• /
• 제44권4호
• /
• pp.397-407
• /
• 2018

Objectives: The purpose of this study is to investigate human health risk assessment of indoor air pollutants at small-sized public-use facilities (e.g., daycare centers, hospital and elderly care facilities) that the susceptible population is mainly used. Methods: To assess indoor air quality (IAQ), the concentrations of indoor air contaminants such as HCHO, benzene, toluene, ethylbenzene, xylene, styrene, PM-10, CO, $NO_2$ and $O_3$ in air samples were measured according to the Indoor Air Quality Standard Method. By conducting the questionnaire survey, the major factors influencing IAQ were identified. Human health risk assessment was carried out in the consideration of type of use (user and worker) at 75 daycare centers, 34 hospitals and 40 elderly care facilities. Results: As a result of measurement of indoor air contaminants, the average concentration of HCHO and TVOCs in hospitals was higher than daycare centers and elderly care facilities, about 8.8 and 23.5% of hospitals were exceeded by IAQ standard. In human health risk assessment, for the user of daycare centers and elderly care facilities, the mean carcinogenic risk of HCHO inhalation was higher than acceptable value. Except for HCHO, other values were determined under acceptable risk. Similarly, for the worker of hospitals, the mean carcinogenic risk of HCHO inhalation was higher than acceptable value and other values were evaluated under acceptable risk. In contrast, the risk levels of other contaminants measured in elderly care facilities were acceptable. In the determination of factors influencing IAQ, the construction year, building type, ventilation time, and the use of air cleaner were identified. Conclusions: This study provides the information for establishing the plans of public health management of IAQ at small-sized public-use facilities that have not yet been placed under the regulation. The findings suggest the consideration of human health risk assessment results for the IAQ standards.

• 지역사회간호학회지
• /
• 제19권1호
• /
• pp.27-35
• /
• 2008

Purpose: The purpose of this study was to examine the effects of aroma-inhalation on depression, sleep, mood, and smell in stroke patients and their caregivers. Method: This study employed one group pretest-posttest repeated design. Data were collected at three time points: baseline(pre-test), 10 days and 20 days after the intervention(Post-test1 and post-test2, respectively). The sample included a total of 23 subjects. Data were analyzed by SPSS 12.0 program using repeated measure ANOVA. Results: Depression was not statistically significant difference among pre-test, post-test1 and post-test2. Sleep was improved after intervention $37.61{\pm}7.41$(pre-test), $41.22{\pm}8.26$ (post-test1), $44.33{\pm}7.67$(post-test2) (F=8.182. p=.001) Mood was significantly improved after intervention: $16.95{\pm}4.89$(pre-test), $14.89{\pm}6.31$(post-test1), $12.11{\pm}5.04$(post-test2). Smell including smell perception, discomfort due to smell and relation between age and smell was significantly improved after intervention: $2.63{\pm}1.20$ (pre-test). $2.00{\pm}1.16$(post-test1), $1.63{\pm}.96$(post-test2) (F=6.176. p=.006) in smell perception, $2.50{\pm}1.10$ (pre-test). $1.81{\pm}.91$(post-test1), $1.19{\pm}.40$(post-test2) (F=12.26. p=.000) in discomfort due to smell and $3.53{\pm}1.18$(pre-test). $2.59{\pm}1.46$(post-test1), $2.53{\pm}1.33$(post-test2) (F=4.148, p=.025) in relation between age and smell. Conclusion: The results suggest that aroma-inhalation may have an effect on sleep, mood and smell and can be effective nursing intervention to increase the relaxation in stroke patients and their caregivers.