정수처리용 막분리 공정의 운전인자에 관한 연구

문성용,김승현 慶南大學校 附設 工業技術硏究所 2002 硏究論文集 Vol.20 No.-

정수처리 과정에서 수중 자연유기물(NOM)은 THMs과 HAA와 같은 소독부산물의 발생원인 물질로 잘 알려져 있다. NOM의 대표적인 제거 방법은 오존산화와 입상활성탄여과 공정, 그리고 최근 막분리 공정이 본격적으로 적용되고 있다. 본 연구는 막분리 공정을 정수처리공정에 적용하고, 운전인자들에 대한 고찰을 통해 적정한 운전 방법을 제시하고자 한다. 본 연구의 결과 한외여과막과 나노여과막의 경우 TOC 제거율을 각 41%와 88% 이상 높일 수 있었다. 또한 운전 인자들에 대해서는 J/k 비의 증가에 따라 막오염 증가와 제거율 감소가 크게 발생하였다. 적용 압력의 경우 최적의 적용압력이 존재하며, 이상의 압력조건에서는 오히려 낮은 효율을 나타내었다. Natural organic matter(NOM) was know to disinfection by-products as THMs, HAA in water treatment process. Its typical removal methods is ozonation +GAC process and membrane separation process. In this paper research on NOM removal character useing the membrane separation process in conventional water treatment plants. Consideration of membrane process operating factor, show that optimum operation condition. The result of this study that used of UF and NF membrane in TOC removal rate increased to over 41% and 88%. Operate factor was J/k ratio and trans membrane pressure. Increase of J/k ratio was to considerably increase membrane fouling and decrease removal rate.

혈청 Glutamic oxalacetic transaminase(SGOT) 측정 방법의 비교실험에 관하여

최인성,장문기,문영희,백승룡 대한병리학회 1975 Journal of Pathology and Translational Medicine Vol.9 No.2

치주조직 재생을 위한 칼슘 포스페이트 글라스 분말이 백서 두개골 결손부의 골조직 재생에 미치는 영향

이용근,문현주,이상배,김광만,김경남,최성호 大韓齒科器材學會 2003 대한치과재료학회지 Vol.30 No.2

The treatment of the tone defects resulting from trauma, neoplasm, surgery, or infection is one of the major concern in dentistry. The major goal is the functional, esthetical regeneration of supporting structures already destructed by disease. Transplantation technique have been used to provide a scaffold for bone regeneration, to augment bony defects resulting from trauma or surgery, to restore bone loss caused by dental disease, to prevent the collapse the alveolar ridge in recent extraction sites, to replace bone loss by periodontal disease, to augment the alveolar ridge in implant surgery. There are autogeneous, allogenic, xenogenic and alloplastic bone-grafts in transplantation. Among the alloplastic bone-graft materials, calcium phosphates have been received the most attention. In this study, the critical size defects were surgically produced in the calvarial bone of Sprague-Dawley rats using the 8 ㎜ trephine bur. Calcium phosphate glass powders with mean diameter 400 ㎛ transplanted onto the produced detects in the experimental group, while sutured without grafting anything in the control group. Histomorphometric as well as radiodensitometric analyses were performed after sacrifice at 2, 4 and 8 weeks following operation. The prepared calcium phosphate glass powder with average size 400 ㎛ in CaO-CaF_2-P_2O_5-MgO-Al_2O_3 promoted new bone formation in the calvarial defects in the Sprague-Dawley rats. New bone was formed in the upper side of the detects as well as the defect margin and dura mater. Experimental group always exhibited higher values in the length, area and density of the newly formed bone than that of the control group. There were significant differences between the experimental and the control groups, except the density after 4 weeks (p<0.05).

암환자의 뇌혈관질환

이지용,권준범,양현덕,이성익,한범기,문준식,이성수 대한신경과학회 1999 대한신경과학회지 Vol.17 No.6

특수위치에 있는 원자들의 비등방성 온도인자

김용채,이창희,이진호,서일환,추금홍,이정수,성백석,김문집 순천향대학교 기초과학연구소 1998 순천향자연과학연구 논문집 Vol.4 No.2

The anisotropic thermal factor of an atom located at a general position has six parameters as follows: ?? If the atom is placed at a special position, the anisotropic thermal factor must have the same symmetry as the special position has. The symmetries at the special positions reduce the 6 anisotropic thermal parameters to 4 or 3 or 2 or 1 and there are 18 different kinds of anisotropic thermal factors altogether for special positions in 230 space groups.

모세관 전기영동법을 이용한 1,2,4-트리메틸벤젠 대사체의 분석

강종성,홍정희,임정미,이용문,장재연 충남대학교 약학대학 의약품개발연구소 1999 藥學論文集 Vol.15 No.-

방향족 탄화수소인 tnmethylbenzene (TMB)은 그 사용량이 늘어갈 뿐 아니라 직업적으로 폭로되는 양도 증가하고 있으므로 생물학적 모니터링 및 흡수, 대사, 배설에 관한 연구가 중요시되고 있다. 일반적으로 TMB는 간의 산화효소에 의해 하나의 메틸기가 산화되고 이것은 glycine과 포합되어 배설되는 것으로알려져 있다. 본 연구에서는 1,2,4-TMB의 대사체를 합성하고, 모세관의 전기영동법으로 분석할 수 있는 방법을 개발하였다. 모세관 전기영동법으로 흰쥐의 뇨 중에서 1,2,4-TMB의 대사체인 3,4, 2,4, 2,5-dimethylbenzoic acid 및 3,4 2,4 2,5-dimethylhippuric acid를 분석하기 위하여 내경 75㎛, 총길이 35cm (검출기까지 29cm)인 용융실리카 모세관을 15℃로 유지하면서 양단에 10kV의 전압을 걸어주고, 전해질로는 15mM β-CD, 3% 2-프로판올을 포함하는 01m 인산완충액 (pH 7)을 사용하였으며, 검출신호는 UV 210nm와 254nm에서 동시에 모니터링하였다. 뇨 시료의 분석 결과 배설된 1,2,4-TMB의 대사체의 상대량은 3,4-이성질체가 56.&%, 2,4-이성질체가 30.5%, 2,5-이성질체가 12.8%였다. 이 방법은 노동자의 뇨 분석에도 적용될 수 있을 것으로 생각된다. The metabolites of 1,2,4-trimethylbenzene (TMB) were synthesized and determined by capillary electrophoresis (CE). The optimum conditions of CE for the separation and determination of 3,4-, 2,4-, 2,5-dimethylbenzoic acid and 3,4-, 2,4-, 2,5-dimethylhippuric acid from the rat wine were as following: the fused silica capillary(75μm i.d. X 36 cm length, 29 cm to detector) was used and kept at 15℃ The applied voltage was 10kV and compounds were detected at UV 210 nm and 254 nm. The running electrolyte was 0.1 M phosphate buffer (pH 7) contalI1ing 15 mM of β -CD and 3% of 2-propanol. The relative amount of the metabolite of 1,2.4-TMB in the rat urine was 56.7% of 3,4-isomer, 30.5% of 2,4-lsomer and 12.8% of 2,5-isomer. This method can be applied to the analysis of TMB-metabolites in human wine.

전력계통의 전압붕괴에 관한 연구

한성문,왕용필,정형환,주수원 동아대학교 공과대학 부설 한국자원개발연구소 1995 硏究報告 Vol.19 No.1

This paper analyzed the static voltage collapse phenomenon and the dynamic voltage collapse phenomenon by means of fluctuations of active-reactive power and the fluctuations of active power offered an output from the load bus respectively. The results are summarized as follows 1. In static state, the voltage collapse value can be computed by applying the equilibrium equation of active- reactive power to Jacobian, the bifurcation point can be also found. 2. The voltage collapse broke out by the reactive power loss and it is found that the active power has an effect on the voltage collapse phenomenon. 3. When a disturbance is given to the active power of the infinite bus voltage side, it is showed that a voltage is collpased by change of the load angle and the current in a dynamic fuctuation of the transient internal voltage E'_(q), E'_(d).

초내열합금 CM247LC의 미세조직 및 인장 특성에 미치는 진동 및 접종처리의 영향

徐晟文,芮大喜,金仁守,趙昌龍 대한금속재료학회 2002 대한금속·재료학회지 Vol.40 No.12

Effects of vibration(V) and inoculation(I) during casting on the microstructure and tensile properties of nickel-base superalloy CM247LC were investigated. The vibration treatment with a frequency of 10 ㎐ was effective to refine the grain size and decrease the microporosity level to some extent. The vibration treatment for the inoculated mold developed the grains of the casting into fine equiaxed grains compared with columnar grains of the casting with vibration free inoculated mold. The existing phases of CM247LC alloy such as finely dispersed cuboidal γ', MC, and grain boundary precipitates were not influenced by the vibration and/or inoculation treatment. The fine equiaxed grained CM247LC had excellent tensile properties compared with those of the columnar grains. The tensile behavior of CM247LC alloy at 760℃ showed different aspects with respect to the grain size change and which was carefully analyzed by fractographic investigations.

일방향응고 초내열합금 CM186LC의 크리프 및 저주기피로 균열생성

趙昌龍,金豆炫,崔承柱,徐晟文,李在鉉 창원대학교 공작기계기술연구센터 1999 연구업적집 Vol.1 No.1

The second generation DS alloy CM186LC has comparable creep-rupture life to first generation single crystal alloys CMSX-2 and CMSX-3 in the as-cast and double aged condition. In the assembly of nozzle guide vanes, Ds components are joined into pairs by brazing. In order to study mechanical behavior of the material at the same condition as production, DS bars were subjected to brazing simulated treatments. Compared with standard treatment a small drop in creep-rupture life was observed but the degree of fall in life was not serious. Creep cracks initiated at the transverse components of the grain boundaries, which were normal to the applied stress direction. Every crack was associated with the v-v' eutectic phase at grain boundaries v-v' eutectic was not only located at grain boundaries but also in the interdendritic regions. It also acted as crack initiation site during creep. Low cycle fatigue tests were conducted under fully reversed trapezoidal strain wave at a frequency of 0.25Hz. The depth of the LCF cracks at the surface was comparable to that of the secondary dendrite arms from the surf-ace of the specimen. Cracks initiated at all of the interdendritic regions exposed at the surface, especially at the v-v' eutectic phase. LCF crack initiation and propagation are therefore proposed to be microstructally dependent.

醫療過誤로 인한 被害의 私法的 救濟

洪天龍,文聖蹄 慶南大學校法學硏究所 1999 慶南法學 Vol.15 No.-