석영과 장석의 Zeta 전위에 있어서 금속이온의 영향

오재현,박광원,이원해,원덕환 대한금속재료학회(대한금속학회) 1974 대한금속·재료학회지 Vol.12 No.4

石英과 長石의 活性化에 關한 資料를 얻기 爲해서 水溶液中 Mg^(++), Cu^(++), Zn^(++)과 Al^(+++)를 添加하여 鑛粒의 Zeta 電位를 測定하였다. 그리고 이들 鑛粒의 界面電氣現象과 金屬이온들의 加水分解特性을 서로 關聯시켜 比較 檢討하여 다음과 같은 結論을 얻었다. 1. 水溶液中에 金屬이온이 存在할 때 長石의 界面電氣現象은 石英과 같다. 2. 金屬이온種의 吸着으로 因해 石英과 長石의 界面은 陽(+)으로 荷電된다. 그리고 陽으로 荷電되는 pH 範圍는 金屬이온의 種類에 따라 다르다. 3. 水溶液中에 金屬이온들이 存在하면 鑛粒의 zpc(Zero point of charge)는 두 곳의 pH에서 나타난다. 두개의 zpc 중 하나의 zpc가 나타나는 pH는 M^(II)OH^+, M^(III)(OH)^+_2 및 M^(III)(OH)^(++) 이온種의 最高濃度가 나타나는 pH와 거의 一致한다. 마그네슘 이온의 경우에는 pH 10.1에서 단하나의 zpc가 나타난다. 4. Mg(II), Cu(II), Zn(II) 및 Al(III) 이온들의 加水分解特性과 zeta 電位를 關聯시켜 볼 때 Mg^(++), Cu^(++), Zn^(++) 및 Al^(+++)은 鑛粒表面에 對해 吸着力이 弱하고, 한편 M^(II)(OH)^+, M^(III)(OH)^+_2 및 M^(III)(OH)^(++) 이온種은 吸着力이 强함을 알 수 있다. To obtain a better understanding of quartz and orthoclase activation, zeta potentials of the minerals were studied in the presence of metallic ions such as Mg^(++), Cu^(++), Zn^(++) and Al^(+++). A microelectrophoresis technique has been used to measure the zeta potential, and the results have been correlated with the hydrolysis of the metallic ions in the solution. The experimental results have led to the following conclusions. 1. Zeta potentials of orthoclase in the presence of the metallic ions show a similar behavior to those of quartz. 2. Adsorption of the metallic ions renders the zeta potential of quartz and orthoclase positive. The pH range of positive zeta potential varies with the kind of cation. 3. Zero point of charge(ZPC) of the mineral surface in the presence of metallic ions appears at two different pH of solution. One of two pH of ZPC is consistent with the pH at which M^(II)(OH)^+ and M^(III)(OH)^+_2 or M^(III)(OH)^(++) species are predominant. 4. Comparison of the zeta potential data with the hydrolysis for Mg(II), Cu(II), Zn(II) and Al(III) species suggests that Mg^(++), Cu^(++), Zn^(++) and Al^(+++) are only weakly adsorbed at the mineral surface and that M^(II)(OH)^+ and M^(III)(OH)^+_2 or M^(III)(OH)^(++) are the main metallic ionic species adsorbed.

EAF Slag의 해양복토제 활용을 위한 PO₄<SUP>­</SUP>-P 제거특성에 관한 연구

김재원(Jae-Won Kim),서종범(Jong-Beom Seo),강민경(Min-Gyeong Kang),김인득(In-Deuk Kim),오광중(Kwang-Joong Oh) 한국청정기술학회 2010 청정기술 Vol.16 No.4

Oxalate와 Enrofloxacin투여한 랫트신장에 대한 병리조직학적관찰

오원석,이차수,오규실,정원일,정재용,정다히,정규식 한국임상수의학회 2003 한국임상수의학회지 Vol.20 No.4

To investigate the renal effects of enrofloxacin administration on rats induced with dehydration or hyperoxaluria, male rats were treated with enrofloxacin of 50 mg to 500 mg/kg b.w.. The microscopical observations of kidney and urine sediment were carried out in the experimental groups. The result obtained were as follows; The male rats deprived of water for 72 hours and administered with enrofloxacin. As enrofloxacin administration dose was increased, clinical signs such as loss of appetite, depression, weakness, and loss of urine output became more severe. In the histopathological findings, there were hyperemia and hemorrhage in renal cortex, vacuolation and necrosis of renal tubular epithelia, proteinous casts within renal tubules. The male rats were orally administered with sodium oxalate and injected with enrofloxacin for 7days. As enrofloxacin administration dose was increased, clinical signs such as the loss of appetite and water consumption, and weakness became more severe. In the histopathological findings, there are hemorrhage of glomeruli and cortical hyperemia, vacuolation and necrosis of tubular epithelia, proteinous casts in renal tubules. In the microscopical findings of urine sediment, there are calcium oxalate crystal (diamond-like type) and magnesium ammonium phosphate crystals (rhomboid). The male rats were intraperitoneally injected with sodium oxalate and administered with enrofloxacin for 7days. As enrofloxacin administration dose was increased, clinical signs such as the loss of appetite and water consumption, weakness were more severe. In the histopathological findings, there were hyperemia and hemorrhage in both glomeruli and renal cortex. Severe necrosis of renal tubular epithelia, bluish materials within renal tubules were also found. In the microscopical findings of urine sediment, there were many calcium oxalate crystals. The present results suggest that enrofloxacin has some injurious effects in rats having dehydration or hyperoxaluria, and clinically, we should consider these renal injury effects when we use enrofloxacin in patients accompanied renal disease, dehydration and hyperoxaluria conditions.

계장화충격시험에 의한 복합조직강의 파괴인성에 관한 연구

오세욱,유재환,박원조,이경봉 동아대학교 공과대학 부설 한국자원개발연구소 1989 硏究報告 Vol.13 No.1

The dynamic fracture toughness (K_(Id)) is measured using the precracked standard Charpy specimen with an instrumented impact machine. The value of K_(Id) is determined as a function of yield strength and microstructure, and correlations are established between K_(Id) and both energy of initial fracture and total energy of fracture. Since the K_(Id) values of the precracted impact specimens are in accordance with their theoretical ones, this test method is sufficiently practical.

(Ba, Sr, Mg)TiO₃를 이용한 입계층 캐패시터의 제작 및 유전특성에 관한 연구

오의균,박태곤,강도원,오재유,김범진 창원대학교 공작기계기술연구센터 1999 연구업적집 Vol.1 No.1

The (0.8BaTiO₃-0.1SrTiO₃-0.1MgTiO₃)+0.006Nb₂O5 ceramics were fabricated by conventional ceramic process. The dielectric property of specimen was investigated that the specimen was sintering temperature at 1,300℃ for 3hours and them annealed at 1,100℃ for 3hours in a atmosphere (air) to be painted on the surface with CuO paste. The results of the temperature and frequency are varied, the dielectric constant and loss tangent are unsuitable for BL capacitor. The dielectric constants were varied to be negative temperature coefficient(2,000∼3,000) in the temperature range between -10 and 140℃, the dissipation factors (tan δ) were some high(0.1∼0.3). It was not grain insulation, in cause of the some difficult to be annealed temperature with CuO paste and fired atmosphere. But, we have some different annealing temperature and fired atmosphere. it will be suitable BL(Boundary Layer)capacitor.

濕式法에 依한 輝安鑛으로부터 三酸化 안티모니의 製造에 關하여

오재현,김준수,고인용,정원용 연세대학교 산업기술연구소 1979 논문집 Vol.11 No.1

An investigation on the production of high purity Sb₂O₃was carried out by means of the acid leaching process from the roasted ore of stibnite. The approach of these studies has been to investigate purity, particle size, recovery and crystal structure of Sb₂O₃obtained through the subsequent treatments of leaching, hydrolysis and neutralization under various conditions. The results obtained in these experiments are summarized as follows; 1) It was possible to use dilute hydrochloric acid to extract Sb₂O₃from the roasted stibnite. Because of the prior roasting treatment, the contamination of impurities could also be reduced in the final products. 2) The rate of extraction of Sb₂O₃from the roasted stibnite was increased concentration of hydro-chloric acid as increased amount of addition of the acid. 3) The yield of Sb₂O₃obtained by hydrolysis of SbCl₃was increased with increasing temperature of hydrolysis. 4) The crystal structure of Sb₂O₃obtained by hydrolysis of SbCl₃at 20℃(room temperature) was confirmed as a orthorhombic crystal structure which is the same as that of valentinite. The recovery of Sb₂O₃from the roasted ore appeared to be nearly 100% under optimum conditions.

Rhinocerebral Mucormycosis 2예

오명돈,최강원,김병국,김재중,이홍규,김상윤 대한감염학회 1986 감염 Vol.18 No.2

Mucormycosis is an acute suppurative opportunistic mycosis that produce predominantly rhinocerebral disease in patient with diabetic ketoacidosis and immunosuppressed patient. We experienced two cases of rhinocerebral mucormycosis recently. The one occurred in patient with diabetic ketoacidosis and the other in acute leukemia. They showed nasal discharge, orbital cellulitis and proptosis. Their condition rapidly deteriorated. Biopsy from palate and sinus revealed broad, nonseptate, right-angled branching hyphae, a finding compatible with mucormycosis.

비장경색이 동반된 쯔쯔가무시병 1예

오종찬,이범주,장재현,원경준,박경희,김동민,박치영,정춘해 朝鮮大學校 附設 醫學硏究所 2005 The Medical Journal of Chosun University Vol.30 No.1

Tsutsugamushi disease is an acute febrile illness caused by Orientie. tsutsugsmushi. It is characterized by fever, myalgia, lymphadenopathy, and rash. And it can be easily diagnosed by characteristic eschar and serologic testing. Nearly all of the patients with tsutsugamushi disease improve with antibiotics such as doxycycline. However, the fatality rate of untreated cases is seven to ten percent. Splenic infarction is not common disease which is caused by occlusion of the main splenic artery or any of its branches. It is mainly caused by emboli that arise from cardiovascular disease, but sometimes by regional thrombosis associated with leukemia, myeloproliferative disorder, sickle cell anemia, pancreatitis, splenic torsion and septicemia. We experienced one case of tsutsugamushi disease with splenic infarction, which was improved after doxycycline treatment finished.

흉요추 방출성 골절의 방사선학적 소견

오연희,이현경,이원재,이성우,박수성 동국대학교 경주대학 1993 東國論集 Vol.12 No.-

A retrospective review of 22 burst fractures of the thoracolumbar spine was performed to define the radiographic features found on CT and plain radiography. Characteristic components of the injury include : 1. Male to female ratio was 2.7 : 1, and the most prevalent age was 21 to 40 years. 2. Multiple level injuries were 6 cases (27.3%), and the most common cause of injury was fall down(14 cases, 63.6%). 3. The most cammon location was L1(45.5%) 4. The most common pattern of the retropulsed fragment in burst fracture was single midline fragment type(14 cases, 63.6%) and the most common type of burst fracture was classical form(10 cases, 45.5%). 5. Posterior element involvement of vertebra was seen in Ⅱ cases(50%) and the most common finding was laminar fracture in 9 cases. 6. The degree of anterior wedging above the 50% in height of vertebral body was in 4 cases (18.2%). 7. Degree of spinal canal narrowing and degree of neurological impairment is not directly correlated.

HRTF(머리저달함수)의 샘플링률 변환에 따른 입체음향 플레이어

오재경,이동재,임철수,최범석,이원돈 호서대학교 반도체제조장비국산화연구센터 2001 반도체장비학술심포지움 Vol.2001 No.-

본 논문에서는 3D사운드 생성 기술 중 대표적인 방법인 원음에 HRTF(머리전달함수)를 콘볼루션(convolution하는 방식으로 음상정위 모듈을 구현하였으며 음장감을 부여하기 위하여 잔향(reverberation)효과를 추가하고 크로스토크 현상을 제거하기 위하여 트랜스오럴 필터를 추가하였다.본 논문에서는 sampling rate conversion을 사용하여 decimation과 interpolation을 수행하여 44.1KHz의 sampling rate로된 coefficient를 downsample하거나 upsample한 HRTR(머리전달함수)를 사용하여 콘볼루션(convolution)을 수행했다.본 논문에서는 3D사운드 생성과정에서 필요한 연산과정을 최소화하여 일반 PC의 computing power로도 sampling rate conversion된 데이터를 처리하여 줄 수 있는 알고리즘을 제시하고 구현하였다.