분사법에 의한 탄산칼슘 제조

신보철,한상오,김주호,송지훈,송근호,이광래 강원대학교 석재복합신소재제품연구센터 2001 석재연 논문집 Vol.6 No.-

본 연구는 탄산가스화법에 의한 탄산칼슘 입자 제조 공정에 있어서, 탄산가스로 채워진 반응기에 수산화칼슘 슬러리를 분사하는 방법으로 탄산칼슘 입자를 제조하였다. 수산화 칼슘의 농도(0.25~1.0wt%), 분사압력(0.5kgf /㎠~1.5kgf /㎠) 및 반응기 온도(20℃, 28℃)의 변화에 따른 생성된 탄산칼슘을 관찰하였다. 수산화 칼슘의 농도가 비교적 높으면(0.75wt%, 1.0wt%), 생성물의 pH와 전도도는 높게 나타났다. 분사압력에 의한 탄산칼슘 제조의 변화는 분사압력이 높아질수록(1.5kgf /㎠), pH와 전도도는 높게 측정되었다. 그러나, 수산화 칼슘의 농도와 분사압력의 변화가 탄산칼슘의 입자크기, 형태, 결정구조에 영향을 미치지는 않았다. 반응기의 온도가 28℃에서 생성된 탄산칼슘은 1.0㎛이하의 칼사이트 상 입자가 제조되었으며, 20℃에서 생성된 탄산칼슘은 0.5㎛이하의 칼사이트 상 입자가 제조되었다. 반응기의 온도가 낮아질수록 탄산칼슘 입자의 크기가 작아짐을 알 수 있었다. For the preparation of calcium carbonate particles from aqueous Ca(OH)2 slurry, carbonation reaction of aqueous Ca(OH)2 slurry was carried out by spouting the aqueous slurry of Ca(OH)2 into reactor filled with CO2 gas. The concentration of Ca(OH)2 varies from 0.25wt% to 1.0wt%, nozzle pressure from 0.5kgf /㎠ to 1.5kgf /㎠, and reactor temperature were set at 20℃ and 28℃. With relatively high concentration of 0.75wt% and 1.0wt% of Ca(OH)2, pH and conductivity of product-stream were observed high value. High pH and conductivity were observed at high nozzle pressure of 1.5kgf /㎠. The concentration of Ca(OH)2 and nozzle pressure, however, did not change the particle size and shape of calcium carbonate synthesized by carbonation reaction. The reaction temperature affected particle size. At reactor temperatures of 28℃ and 20℃, the particle sizes were about 1.0㎛ and 0.5㎛, respectively. Crystal structure of calcium calcium carbonate was of calcite. When reactor temperature was lower, the size of calcium carbonate particle was smaller.

직업 유무와 진균 감염

오상철,홍성호,조주연 순천향대학교 교수학습개발센터 2004 Journal of Soonchunhyang Medical Science Vol.10 No.3

Back ground : This study was designed to evaluate the relation fungal infection with the males and females with/without occupation and to evaluate cause of fungal infection Methods : This study was done via direct interview and KOH mount with 03 patients who are oupatients in a university hospital from July 2000 to Aprill 2001. They were divided into three groups, males with occupation, females with occupation, females withoup occupation and sudied by sex, age, duration, types of dermatophytosis, site of infection, infection in families. Results : The results were as follows 1. Fungal infection was 40% in males with occupation, 24% in females with occupation, 36% in females without occupation. 2. The site of fungal infection was the offices(42.5%), the families(30%) in men with occupation and the families(54.2%), the offices (41.7%) in females with occupation and the families(72%), the others(11.1%) in females withoup occupation. 3. The members of the families were the spouses(32.5%), the parents or children(32.5%) in men with occupation and the spouses(41.7%), the parents or children(25.0%) in females with occupation and the spouses(69.4%), the parents or children(13.9%) in females without occupation. Conclusions : In our study, the results showed no difference in the fungal infections among males with occupation, females with occupation and females without occupation. Fungal infection of females without occupation was spread in the families and by the pouse among the members of the families

외상성 뇌손상 환자의 지능 장애와 K-WAIS 소검사내 분산도

오상우,김지영,노승호 圓光大學校 醫科大學 神經精神科學敎室 1997 圓光精神醫學 Vol.13 No.2

본 연구는 외상성 뇌손상 환자의 병전 지능을 추정하여, 추정된 지능을 현재 지능과 비교하고, K-WAIS 소검사내 분산도 분석을 시행하여 인지 기능의 효율성을 평가하고자 하였다. 연구 결과, 외상성 뇌손상 환자 집단은 정신분열증 집단이나 기타 임상 집단의 환자들에 비해 지능이 유의하게 저하되어 있었다. 그러나 소검사내 분산도 분석에서는 외상성 뇌손상 환자 집단이 다른 두 집단보다 인지적 효율성이 더 높았다. In this study, premorbid IQ in patients with traumatic brain injury were estimated and compared with measured IQ, and examined efficiency of cognitive function through K-WAIS intrasubtest scatter analysis. These results suggested that traumatic brain injury patient's IQ were significantly lower than those of the schizophrenia and other psychiatric patients. But traumatic brain injury patient's cognitive efficiency were higher than those of the schizophrenia and other psychiatric patients.

제주시 도시관광 발전정책에 관한 연구

吳相勛 제주대학교 동아시아연구소 1998 東아시아硏究論叢 Vol.9 No.-

trans-Dichlorobis-(ethylenediamine) cobalt(Ⅲ)착물과 Pyridine간에 반응속도론적 연구

吳相午,朴裕哲 慶北大學校 1975 論文集 Vol.19 No.-

Rate constants have been obtained for substitution reaction of trans-dichlorobis-(ethylenediamine) cobalt (Ⅲ) complex ion with pyridine and hydrogen ion concentration in mixed aqueous solvents, methanol-water, ethanol-water and acetone-water. The results discussed in terms of the Grunwald-Winstein treatment of substitution at lower pH is increasingly S_N1 mechanism in character, but substitution at higher pH may have a certain degree of S_N2 mechanism in character. And rate of substitution of transdichlorobis-(ethylenediamine)- cobalt(Ⅲ) complex ion with pyridine varies inversely as the hydrogen ion concentration at below pH 5.03. A reasonable mechanism proposed for this reaction is consistent with the kinetic data. The rate equation is derived from the proposed mechanism. And also the rate parameters are obtained from the above results.

임금의 경직성과 자산시장의 기능

오상근 東亞大學校 大學院 1998 大學院論文集 Vol.23 No.-

Wage ridities in the aggregate labor market has long been disputed since Keynes-Dunlop-Tarshis controversies. the purpose of this paper is to partially resolve the labor market puzzle: the weak correlation between real wage and the change in labor time while large fluctuation in the labor time and employment. The key to resolve the puzzle is to introduce precautionary saving behavior inthe asset market. The overlapping generation model in which finitely-lived agents choose labor supply and asset demand produces a "multiplier effect" in the sense that a small productivity shock results in a large and persistent fluctuation of output. The paper also explores some stylized business cycle facts: the opposite movements in leisure and consumption; the positive correlation between average productivity of labor and output; volatility of output is larger than that of consumption.

전로제강 슬래그(BOF-Slag)를 이용한 고온탈황에 관한 연구

오광중,정덕영,최성원,조상원,손병현 釜山大學校生産技術硏究所 1996 生産技術硏究所論文集 Vol.51 No.-

고온 석탄연료가스의 탈황에 BOF-Slag의 이용가능성을 실험해 보았다. BOR-Slag의 온도, 유량, 탈황제의 특성등이 H₂S 제거효율에 미치는 영향을 조사해 본 결과, 최적의 H₂S 제거효율은 700℃에서 이루어졌고 입자크기가 작을수록 황포집능은 향상되었으나 0.214-0.631mm에서는 큰 영향이 발견되지 않았다. 조업온도 800℃이상에서는 탈황제의 응집으로 내부물질전달저항이 증가하여 탈황제의 반응성이 저하되었다. Experiments have been made to test the practical feasibility of using BOF-Slag to desulfurize hot coal-derived fuel gas. In this study, the effects of particle size, temperature, flow rate and sorbent characteristics on the H₂S removal efficiency of BOF-Slag were investigated. Experimental results showed that the removal efficiency of H₂S was optimum when the temperature was about 700℃ and the smaller sample size, the better sorbent capacity had and the sample size in the range of 0.214∼0.631mm didn't influence. When the temperature was above 800℃, the reactivity of sorbent has lowered because agglomeration of sorbent increased intraparticle transport resistance.

88 Olympic 사격선수들의 연령·체격조사 연구

吳成基,李彦鎬 부산 외국어 대학교 1992 外大論叢 Vol.10 No.1

As this is a study for improvement of Korean shooting, it is based on distribution of age and physique of shooters who are person of the 14 advanced sports nation in the world. And the paper show us the following conclusion. 1) The shooters of U.R.S the best rank of the world had very nice physique and average age is male 29, 12(±3.7) and Female 26.7(±3.4) and winner group B.U.L shooters average age Male 29.5(±3.7) and Female 26.7(±4.5) years old. 2) Gold medel and silver medel of average age is 24(±2.7~2.8) years old. 3) The shooters physique is U.S.A, J.P.N is fat and their everage age is the middle of 30(34 ±7.6~10.6) years old. 4) The Korean shooters physique is nice. But, they had high distribution age than common property gold medal or silver medel victor.

HUVEC 세포에서 MMP-2 의 분비에 미치는 성장인자의 효과

오인숙,박종완,소상섭 全北大學校 科學敎育硏究所 2000 과학과 과학교육 논문지 Vol.25 No.-

Vascular endothelial cells release proteinase that degrade the extracellular matrix, thus enabling cell migration during angiogenesis and vasculogenesis. Endothelial cells secrete mainly the proform of matrix rnetalloproteinase-2. Matrix metalloproteinase-2 is Zn^2+ dependent protease produced by a variety of cell types. They have a fundamental role in tissue remodelling, tumour invasion and metastasis. The purpose of this study was to test if growth factors, such as angiopoietin-1, bFGF and VEGF can regulate the secretion of MMPs by endothelial cells. Of these growth factors, we found that VEGF is the strongest inducer of MMP-2 secretion. Both angiopoietin-1 and bFGF also induced the secretion of the MMP-2. VEGF induced MMP-2 secretion in a time- and dose-dependent manner. Pretreatment with phosphatidylinositol 3'-kinase inhibitors had no effect. NF-kB inhibitor, PDTC changed significantly the level of MMP-2 secretion from the cell. These results indicate that MMP-2 stimulates normal cell proliferation, wound healing and tissue remodelling in endothelial cells.

방향족 다가카르복시산들의 이온-쌍 액체크로마토그래피

오해범,정순량,홍성완 우석대학교 부설 기초과학연구소 1996 기초과학연구소 논문집 Vol.1 No.-

C_18칼럼을 정지상으로 한 방향족카르복시산들의 역상액체크로마토그래피에서 teramethylmmonium bromide(TMAB)를 반대이온으로 사용하였을 때 반응메카니즘은 이온-쌍 모델이 우세하였다. 시료들의 용량인자값들은 반대이온의 종류와 농도, 이동상에 들어있는 메탄올과 공존음이온의 농도, pH에 많은 영향을 받았으며 시료에 치환되어 있는 작용기의 종류와 위치에 따라서도 영향을 받았다. 이 결과를 토대로 최적 조건하에서 몇가지 시료의 혼합물들을 효과적으로 분리할 수 있었다. Ion-pair model was predominated over ion-interaction model in the retention mechanism of analytes when tetramethylammonium bromide(TMAB) was used as a counter-ion in the investigation of aromatic polycarboxylic acids on the reversed-phase liquid chromatography by C_18 column as a stationary phase. The capacity factors of analytes were influnced by the type and concertation of counter-ions, concertrations of methanol and co-anion, type and position of functional group, and the PH in mobile phase. Components of analyte mixtuue could be separated under the optimum conditions by this method.