CaO-SiO₂-slag계의 수열반응 속도와 기구

정윤중,이희수,이형복 연세대학교 산업기술연구소 1981 논문집 Vol.13 No.1

The molar ratio of CaO/SiO₂was made to be 0.8 and slag was combined with the same weight percentage of CaO/SiO₂mixture, for the study of kinetics and the reaction controlled steps on the CaO-SiO₂and CaO-SiO₂-slag system. Free lime, free silica and combined water of the specmens were determined with the quantitative methods. The chemical composition of the products, rates of reaction and activation energies were calculated from the above experimental data. The results are followed. 1. For the chemical composition of the products CSHn, CaO-SiO₂-slag system has C/S=1.42, n=1.8 and CaO-SiO₂system has C/S=1.29, n=1.5 2. The reaction controlled steps are changed from phase boundary to diffusion in the process of 10 hours at 152 and 181℃ for CaO-SiO₂-slag system and at 80 and 152℃ for CaO-SiO₂-slag system and at 80 and 152℃ for CaO-SiO₂system. 3. The activation energy for CaO-SiO₂-slag system is 12.2 kcal/mole and for CaO-SiO₂system is 6.6 kcal/mole.

Nd₂O₃가 첨가된 반도성 BaTiO₃자기의 PTCR효과

이형복,이경희,정윤중,박철용 明知大學校 産業技術硏究所 1989 産業技術硏究所論文集 Vol.8 No.-

The room temperature resistivity was minimum value at Nd₂O₃ 0.15 mol% in Nd₂O₃doped BaTiO₃ ceramics. Grain sizes were decreased abruptly with Nd₂O₃ doping amount and the size demonstrated minium of 0.7∼1㎛ at Nd₂O₃ 0.2mol% doped. But the room temperature resistivity and grains size were increased again with increase amount of Nd₂O₃ doping amount. With impurity Al₂O₃ or without Al₂O₃, the above behaviors were similar according to the amount of Nd₂O₃ but the room temperature resistivity was a little decreased when added with Al₂O₃. When ?? was added as a counter dopant, the room temperature resistivity was minimum at 0.09 mol% addition and that time the resistivity anomaly effect was about 4 order.

ZrO₂-CaO계의 침전생성상에 미치는 pH효과

이형복,정윤중,김진규 明知大學校 産業技術硏究所 1988 産業技術硏究所論文集 Vol.7 No.-

The crystal phase of 1000℃ calcined powder, which was coprecipitated from the mixed solution of ZrOCl₂-8H₂O and CaCl₂- 2H₂O was detected by the DTA, XRD and SEM. At that time the mixed solution was varied with ZrO₂/CaO mole ratio, i.e. ZrO₂/CaO=0.7/0.3, ZrO₂/CaO=1/1 and ZrO₂/CaO=0.3/0.7. And also the pH value was controlled with NH₄OH solution as 2,4,6,8,10 and 12, respectively. Each system had the behavior of the formation of monoclinic ZrO₂ with tile lower pH value. The former two system showed the formation orthorhombic CaZrO₃ when the pH was 10 and 12. But at the system ZrO₂/CaO=0.3/0.7, the little amount of cubic ZrO₂ crystal phase was detected to coexist with the orthorhombic CaZrO₃ at pH 12.

환원분위기중에서 크로ㆍ마그내화물의 고온안정성

정윤중,이형복 明知大學校 産業技術硏究所 1987 産業技術硏究所論文集 Vol.6 No.2

The reaction mechanism and the Vaporization of CaO·CrO₃ Compound were studied over the temperature range of 600 to 1200 in Hydrogen atmosphere. The Obtained results are as follows; The reaction of CaCrO₄under the hydrogen atmosphere is assumed to be controlled by the interface chemical reaction and the activation energy is 1 Kcal/mole. When the sintering atmosphere of CaO·CrO₃was changed to the reducing atmosphere, the CaO·CrO₃ compound was prohibited to from which causes pollution and corrosion of products.

T1b 병기의 신세포암에서 수술 후 예후를 예측할 수 있는 임상 및 병리학적 인자에 대한 연구

오승용, 김영원, 윤형윤, 서성필, 이상근, 김원태, 윤석중, 이상철, 김원재, 김용준 충북대학교 의과대학 충북대학교 의학연구소 2014 忠北醫大學術誌 Vol.24 No.1

연구목적: T1병기의 국소신세포암(localized clear-cell renal cell carcinoma)은 근치적신적출술이 나 부분신절제술이 표준치료이며 수술 후 타 병기에 비해 양호한 예후를 보인다. 하지만, 많은 수의 환 자에서 추적관찰 중 재발 및 사망이 발생하는데, 이는 T1b 병기에서 더 높게 보고되고 있다. 본 연구 에서는 국소신세포암 중 T1b 병기의 신세포암에서 표준적 치료 후 환자의 예후에 영향을 주는 임상 및 병리학적 인자에 대하여 알아보고자 하였다. 대상 및 방법: 1999년부터 2011년 까지 5개 기관에서 근치적신적출술이나 부분신제술을 시행 받은 3567명의 국소신세포암 환자들 중 병리학적 병기가 T1b로 확진 된 702명을 대상으로 하였다. 이들 환자가 가지는 임상 및 병리학적 특성 [연령, 성별, 고혈압, 당뇨, 비만도, European Cooperative Oncology Group(ECOG) 수행도, 증상유무, 수술방법, 종양크기, 분화도, 조직학적 형태 등]을 이용 하여 환자의 예후 [무재발생존율(relapse-free survival), 암특이생존율(cancer-specific survival) 및 전체생존율(overall survival)]에 영향을 미치는 인자에 대하여 다양한 방법으로 비교분석 하였다. 결과: 추적 관찰 기간은 34.0개월 (중앙값, 0-152개월)이었으며, 이 기간 중 재발, 사망 및 암특이사 망은 각각 72례 (10.3%), 57례 (8.1%) 및 24례 (3.4%)에서 발생하였다. 단변량 및 다변량 Cox 비례위험회귀분석에서 다양한 인자들이 무재발생존율(당뇨 유무, 종양크기 및 Fuhrman등급), 암특이 생존율(나이, 체질량지수, 당뇨 유무, 종양크기) 및 전체생존율(나이, 체질량지수, ECOG 수행도, 종 양크기)에 영향을 줄 수 있는 독립적 예후인자였다. 결론: 본 연구결과 국소신세포암의 예후를 예측할 수 있는 다양한 임상 및 병리학적 인자를 확인 할 수 있었다. 이러한 위험인자를 가지고 있는 환자는 보다 적극적인 추적관찰을 통하여 재발을 조기에 발 견한다면 이들의 생존율 향상에 많은 기여를 할 수 있을 것으로 생각한다.

프리캐스트 포스트텐션 콘크리트 넓은 보-기둥 내부 접합부의 비탄성 거동

황재환,최윤철,김영찬,김대중,임재형,권기혁,문정호,이리형 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.2(구조계)

The purpose of this paper is to evaluate the response of Precast Prestressed Concrete Interior Wide Beam-Column Joint subjected to cyclic lateral loading. To this end, the experimental investigation was performed with six half-scale specimens of interior connection. The design parameters are the beam to column depth ratio, and the number of tendons within column core. One of the specimens, IJH-6, is modeled for the connection at the top floor of a structure. The test results showed that the specimens sufficiently resist up to limiting drift ratio of 0.035 in accordance with the provisional standard by ACI of acceptance criteria for concrete special moment frames.

포스트-텐션 프리캐스트 외부 넓은 보-기둥 접합부의 비탄성 거동

박상욱,최윤철,김영찬,김대중,임재형,권기혁,문정호,이리형 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.2(구조계)

Experimental results from the cycle lateral load tests for post-tensioned precast wide beam-column connections were presented. Six exterior beam-column assemblages of half scale were tested in the laboratory. The specimens consist of U-shaped precast wide beams and concrete columns. The continuity at the beam-column joint is achieved with the topping concrete and post-tensioning. The specimens were designed with parameters of the beam-to-column depth ration and the number of tendons within column core. The test results showed that the post-tensioned precast wide beam-column connection satisfied the provisional standard by ACI of acceptance criteria for concrete special moment frames.

공침범으로 제조한 마그네시아 부분안정화 지르코니아 소결체의 특성에 미치는 열처리 효과

이재원,오응주,정윤중,이형복 明知大學校 産業技術硏究所 1989 産業技術硏究所論文集 Vol.8 No.-

The powder of ZrO₂-MgO systems prepared by co-precipitation method using ZrOCl₂· 8H₂O and MgCl₂· 6H₂O as the sintering materials. They are sintered and than heat treated to know that effects of agoing time and temperature on mechanical and electrical properties. The powder ZrO₂-MgO systems have∼30nm crystal size and tetragonal phase. The mechanical properties of these partially stabilized ZrO₂- MgO specimens are shown the best value when they are aged at 1,100℃ for 1 hr and at 1,450℃ for 10 hrs, but these are better than those, and while the specimens of 9.5 mole% in these thermal conditions. Electrical conductivities are measured as a function of temperature in the range of 500℃ to 1,000℃. The temperature dependence of electrical doncutivities is shown the activation energies by the heat reat conditions; no heat treating, heat treating at 1,100℃ for 1 hr, and heat treating at 1,450℃ for 10 hrs, and their values are 21.5㎉/㏖, 34.3㎉/㏖, and 43.5㎉/㏖, respectively.

컬럼형 회분건조기를 이용한 벼의 건조에 관한 연구

변유량,최홍식,조형용,권윤중,김주봉 연세대학교 산업기술연구소 1984 논문집 Vol.16 No.1

The vertical column batch dryer which is suitable to Korean farm was constructed and dryer performance was investigated through field test. The effect of a drying air temperature and an airflow rate on the drying rate was studied, and an empirical drying equation was established. The average drying rate of paddy were 1.6-1.8%/hr at the air temperature of 43℃ and the airflow rates of 19.4 - 24.5 CFM/ft². The differences of grain moisture content between the inner and outer layer of vertical paddy bed were 0.5 - 0.9% The effect of a drying air temperature was larger at high airflow rate. At constant temperature, the drying rate was increased as an airflow rate was increased. The empirical drying equation could be expressed as followed: ??=0.9exp(??) Where K=3.22×?? The average whitening ratio of brown rice which was dried with column batch dryer was higher 0.6% than that of sun dried rice.

안면부, 유방 및 상완부에 발생한 홍반성 루푸스 지방층염 1예

송유근,손두식,명형준,이현정,임중규,김순호,김윤아 朝鮮大學校 附設 醫學硏究所 2004 The Medical Journal of Chosun University Vol.29 No.2

Lupus erythematous panniculitis is a chronic inflammatory disease of subcutaneous fat that occurs in 2-3% of patients with systemic lupus erythematosus. Lupus erythematous panniculitis typically presents with firm, indurated subcutaneous nodules or plaques commonly developed in proximal extremities, trunks, head and neck. Face, breast and upper extremities involvement with lupus erythematous panniculitis has been infrequently reported. We report a case of lupus erythematous panniculitis developed in a 27-year-old female confirmed by histologic features and laboratory findings.