폐철을 이용한 크롬(VI)의 환원적 제거

임우택,정용식,유건상,김종현,김영훈 7개 국립대학교 환경연구논문집 공동발행 위원회 2005 공업기술연구 Vol.5 No.-

Cr(VI) is a known toxic heavy metal which is found frequently in many industrial sites. Contaminates soil and ground water with Cr(VI) is a big enviromental concern due to the high toxicity. Permeable Reactive Barrier(PRB)is an innovative remedial technology intensively studied and developed recenty. The most popular PRB material is zero-valent iron which is environmentally favorable and cheap. Scrapped steels and precleaned scrapped steels were tested in this study for Cr(VI). Scrapped steels were precleaned wuth detergent, acetone, hexane.The precleaned scrapped steel showed relatively high reactivity for Cr(VI). The results indicate that the scrapped steel could be used as PRB material after proper pretreatments.

심정지환자에서 epinephrine투여시 혈중 catecholamine의 변화

임경수,황성오,이부수,이강현,이진웅,임종천,김영식,김선만,김 현 대한응급의학회 1995 대한응급의학회지 Vol.6 No.1

Background : Cardiac arrest is a potent stimulus for the release of endogenous catecholamine and high plasma catecholamine concentration has been reported during cardiopulmonary resuscitation(CPR). Few data were present about the clinical effect of high plasma catecholamine and endogenous catecholamine response to exogenous epinephrine administration during CPR. Purpose : This study was designed to evaluate endogenous catecholamine response to cardiac arrest and exogenously administered epinephrine during CPR. Method : In 21 cardiac arrest victims, blood sample for epinephrine and norepinephrine was drawn before and 1 minute after each epinephrine administration during CPR. 1mg of epinephrine was administered immediately after intravenous access and 3 minute interval during CPR. Plasma catecholamines were quantitated by high-performance liquid chromatography. Result : Baseline plasma epinephrine concentraqtion was higher in patients with cardiac arrest than normal controls (985±1627 vs 194±173 pg/ml, p<0.05). Baseline plasma norepinephrine concentration was also elevated in patients with cardiac arrest than normal controls, although statistically insignificnat(1965±4915 vs 360±250 pg/ml). Plasma epinephrine concentration in cardiac arrest patients was significantly elevated after exogenous administration of epinephrine, but its response was blunted after the third does of epinephrine. Plasma norepinephrine concentration in cardiac arrest patients was also elevated, but its response was observed only after the first epinephrine administration. Plasma epinephrine concentration was persistently higher in patients with return of spontaneous circulation (ROSC) than patients without ROSC. there was no significant difference of plasma norepinephrine concentration whether spontaneous circulation was restored or not. Endogenous epinephrine response to exogenous epinephrine was not observed in patients having prolonged arrest time over 20 minutes. Conclusion : Results of this study suggests that significant amount of catecholamine is released by exogenous epinephrine administration in spite of high plasma catecholamine concentration, and degree of endogenous catecholamine response influences resuscitation outcome.

교정용 미니스크류 식립 시 스크류의 길이, 직경 및 피질골 두께에 따른 응력 분포에 관한 3차원 유한요소법적 연구

임종원,김왕식,김일규,손충렬,변효인 대한치과교정학회 2003 대한치과교정학회지 Vol.33 No.1

본 연구는 교정치료 시 고정원 보강을 위해 사용되는 교정용 미니스크류의 길이, 직경 및 피질골 두께에 따른 응력분포 양상을 알아보기 위하여 시행되었다. 미니스크류의 길이와 직경 변화에 따른 응력 분포 양상을 관찰하기 위하여 식립되는 피질골의 두께를 1.0mm로 고정하고 미니스크류의 길이를 6.0mm, 8.0mm, 10.0mm, 12.0mm로, 직경을 1.2mm, 1.6mm, 2.0mm인 3차원 유한요소 모델을 제작하였다. 또한, 피질골의 두께 변화에 따른 응력 분포 양상을 관찰하기 위하여 미니스크류의 길이를 0.8mm로 고정하고 직경은 1.2mm, 1.6mm, 2.0mm로, 피질골의 두께는 1.0mm, 1.5mm, 2.0mm, 2.5mm인 3차원 유한 요소 모델을 제작하였다. 각각의 유한요소 모델의 미니스크류 head 중심에 200gm의 수평력을 가하여 응력 분포 양상과 크기를 3차원 유한요소 해석 프로그램인 ANSYS응 이용하여 비교한 결과 다음과 같은 결론을 얻었다. 1. 미니스크류 내부에서 나타나는 최대 응력값을 비교한 결과, 미니스크류의 직경이 1.2mm에서 2.0mm로 증가할수록 응력이 감소하였으며 같은 직경에서는 길이 증가에 상관없이 일정한 값을 유지하였다. 2. 피질골 및 해면골에 작용되는 최대 응력값을 비교한 결과, 미니스크류의 직경이 1.2mm에서 2.0mm로 증가할수록 응력이 감소하였으며 같은 직경에서는 길이 증가에 상관없이 일정한 값을 유지하였다. 3. 피질골 및 해면골에 작용되는 응력 분포를 관찰한 결과, 대부분의 응력이 피질골에서 흡수 되었으며, 해면골에 전달되는 응력값은 미미하였다. 4. 피질골 두께에 따른 최대 응력값을 비교한 결과, 같은 미니스크류의 직경에서는 피질골의 두께 증가에 상관없이 일정한 값을 유지하였다. 이상의 결과는 교정용 미니스크류의 유지에 길이보다는 직경이 더 크게 관여하는 것으로 나타나 미니스크류의 식립시 이에 대한 고려가 필요함을 시사하였다. The purpose of the present study is to evaluate the stress distribution on the length and diameter of the miniscrew and cortical bone width. Three dimensional finite element models were made of diameter 1.2mm, 1.6mm, 2.0mm and length 6.0mm, 8.0mm, 10.0mm, 12.0mm and cortical bone width 1.0mm. Also, another three dimensional finite element models were made of diameter 1.2mm, 1.6mm, 2.0mm and length 8.0mm and cortical bone width 1.0mm, 1.5mm, 2.0mm, 2.5mm, Two-hundred grams horizontal force were applied on the center of the miniscrew head and at that stress distribution and its magnitude had been analyzed by ANSYS, which is three dimensional finite element analysis program. The obtained results were as follows : 1. The comparison of the maximum von-Mises stress in the miniscrew showed that as the diameter increases from 1.2mm to 2.0mm stress has been decreased, while on the same diameter stress was not changed regardless of the length change. 2. The comparison of the maximum von-Mises stress in the cortical and cancellous bone showed that as the diameter increases from 1.2mm to 2.0mm stress has been decreased, while on the same diameter stress was not changed regardless of the length change. 3. In the analysis of the stress distribution in the cortical and cancellous bone, the most of the stress had been absorbed in the cortical bone, and did not transmitted much to the cancellous bone. 4. In the analysis of the maximum von-Mises stress according to the cortical bone width, the same diameter of the miniscrew showed a constant stress value regardless of the cortical bone width change. The above results suggest that the maintenance of the miniscrew is more reliable on diameter than length of the miniscrew.

Effect of Photoperiod, Temperature and True-leaf Stage in Bolting Rate of Chicory (Cichorium intybus L. var. sativus)

Lim,Jung-Dae,Seo,Jeong-Sik,Lee,Hyeon-Yong,Kim,Jong-Dai,Lee,Jin-Ha,Yu,Chang-Yeon 한국자원식물학회 2004 Plant Resources Vol.7 No.1

Root chicory (Cichorium intybus L. var. sativus) is potential alternative medicinal and sugar crop which accumulates a high amount of linear polyfructan, inulin in its roots. A problem in root production is that over-wintered stock plants often flower. Once the plant becomes reproductive, stem elongation and root growth slows and floral buds arise from every node, rendering the plants useless for propagation. The objectives of this research was to examine the effectiveness of manipulating environmental factors containing photoperiod, temperature and number of leaf states. The experiment was performed in growth chamber to create two photoperiods (8 h, and 16 h) with three temperature regimes (5℃/3℃, 10℃/8℃, and 15℃/13℃ day/night temperature) for a total of six treatments on three type of true-leaf stage of plant. Data of bolting rate, shoot and root length, shoot and fresh weight was invetigated in each treatments. This is the first report on changes in bolting rate and shoots and roots production during a whole growing season and differences in the effect of cold and photoperiod treatment depending on the true-leaf stage of plant.

낙동강 상수원수의 오존처리 효과 : II. 회분식 오존처리에 의한 휘발성유기화합물 및 조류제거 효과 II. Removal of VOCs and Algae in Raw Water by Conducting Batch Test of Ozonation Experiments

임영식,이홍재,이도진,허종수,손보균,조주식 한국환경과학회 2002 한국환경과학회지 Vol.11 No.12

This study was carried out to evaluate the pollutant removal efficiencies of the advanced drinking water treatment using ozonation process. For raw water, Nakdong River was used. By conducting batch test of ozonation efficiencies of the ozonation were 94 to 92%, respectively. Removal efficiencies of single VOC compound or mixed VOC compounds in the raw water were 80% to 90% by the ozonation with 2 mg/ℓ dosage and 10 minutes contact time. Removal efficiencies of ABS by the ozonation with 1 mg/ℓ, 3 mg/ℓ dosage and 20 minutes contact time were 83% to 96%, respectively. Almost 67% of chlorophyll-a at the concentration of 38.㎍/ℓ was removed by ozonation at ozone dosage of 1mg/ℓ for 20 min. considering the efficiency of ozone utilization and water treatment, the most effective ozonation could be obtained with high ozone dosage and short and short contact time.

기술적 진화재의 대체모형

임종인,오형식 한국경영과학회 1993 한국경영과학회지 Vol.18 No.3

In this study, a substitution model of the evolutionary generations of technological products is presented. The purpose of the model is to examine the demand side mechanisms which generate successive product life cycles along the path of technological improvements. In the model, the nature of substitution processes is summarized to the demand function which is derived from the consumer's utility maximization problem. To describe the nature of technological substitution processes, the concepts of the vertical differentiation and the consumption externalities are considered in the utility function. The former is used to characterize the result of technological improvement and the latter is used in explaining the inertia of demand. To show the validity of the model, an empirical study is carried out using the data of the world DRAM market.

축구포지션별 무산소 운동능력 분석

손장식,정정욱,김종호,임정수,김훈 대구대학교 기초과학연구소 2003 基礎科學硏究 Vol.19 No.3

In this study, the Wingate power test was performed to investigate of the anaerobic power output in soccer players who play in different position. The main purpose of the test was to provide the enhancement of anaerobic capacity which was conducted by comparing and analysing of the Wingate test. This will improve the performance during the soccer games. Seventeen soccer players with three different positions, FW, MF, DF, were recruited, and undertook the Wingate power test, and anaerobic power, peak power output, anaerobic capacity, and fatigue index was analysed. There was a significant effect of a peak power output among positions showing MF>DF>FW (P<.05). MF revealed the highest peak power output at 15 and 30 seconds time points compared to DF and FW. As far as the players' positions were concerned, a relative anaerobic capacity showed a similar results with a peak power output (P<.05; MF>DF>FW). Unlike with these results, the fatigue index in different positions did not show any statistical significant results (P>.05). Based on these results, it was suggested that the systematical training program is required to perform a modern soccer, pressure and total soccer, in MF players. If the physical strength, especially power out, in MF players is enhanced, the results of the soccer games will be also improved.

레이저에 의한 유리내부의 첨가이온의 전하상태 변화

임기수, 장경식, 신종호, 이수천 忠北大學校部設基礎科學硏究所 2006 自然科學硏究 Vol.20 No.-

-본문참고-

RAW264.7 세포에서 interferon-r 및 LPS에 의해 유도되는 NO생성에 미치는 TALT-35의 영향

박종일,박경석,김종석,박지훈,윤은진,송경섭,서강식,김훈,윤완희,박승길,임규,황병두 충남대학교 생물공학연구소 2006 생물공학연구지 Vol.12 No.-

TALP-35 purified from human term placenta is known to increase microtubule polymerization and stabilize the polymerized microtubule. To examine the effect of TALP-35 on immune system this study was performed. MTT assay was performed to investigate the effect of TALP-35 on the proliferation of RAW264.7 cells. TALP-35 dose dependently suppress the proliferation of RAW264.7 cells at high concentration (above 1 μM) in unstimulated cells, in case of 10 μM TALP-35 treated cells the suppression was 25% but in stimulated cells it was only 15%. Cosedimentation assay was carried out to investigate whether TALP-35 can bind to tubulin of RAW264.7, monocyte/macrophage lineage of mouse, and polymerize it. TALP-35 polymerize the tubulin of RAW264.7 cells and sedimented in dose-dependent manner. To investigate the effect of TALP-35 on the expression of iNOS protein western blotting was performed. The expression level of iNOS was decreased dose dependently in high concentration of TALP-35 treatment. To examine the activity of iNOS, secreted NO was determined by method based on Griess reaction. Interferon-γ and LPS-stimulated production of NO from RAW264.7 cells was decreased dose dependently above 0.1 μM concentration of TALP-35 and 50% is decreased at 10μM of it. This study shows TALP-35 can control cytokine induced-iNOS expression therefore it might control inflammatory diseases.

銅鑛山廢水로부터 分離한 구리 耐性菌(P.stutzeri)의 菌體內 구리 蓄積 特性

許鍾秀,曺周植,韓文圭,李洪宰,林永成 경상대학교 환경보전연구소 1994 環境保全硏究所報 Vol.2 No.1

Of the copper-tolerant 215 bacterial strains isolated from polluted river water, wastewater and activated sludges of wastewater treatment plants, or wastewater and soils of the copper mine aera in Gyeongnam province a strain, which showed considerably higher growth rate in the agar plate containing 2000ppm of copper than any other strains, was identified as a Pseudomonas stutzeri or its similar strain when analyzed by taxonomical charicteristics. Optimum pH and temperature for the growth of the P. stutzeri were 7.0 and 30℃ respectively. This strain was resistant to antibiotics, such as ampicillin and tetracycline, and heavy metals, such as lead and chromium. This strain utilized phenol benzen or toluene as a sole carbon source. The rate of copper accumulation in P. stutzeri cell was enhanced at low concentration of Cu in the growth media. The maximum copper absorption by this strain grown in 10ppm of Cu at 3 days after culture was 49%, but in 50ppm and 100ppm of Cu was 38% and 32%, respectively. The optimal temprature and pH for the effective intracellular accumulation of copper were 30℃ and initial pH 8.0 under shaking culture.