증기상 Beckmann 전이 반응에 대한 Aluminophosphate 분자체의 촉매 특성

윤영삼,박판욱,권성헌,김병주 釜山大學校生産技術硏究所 1997 生産技術硏究所論文集 Vol.53 No.-

Molecular sieves인 AIPO₄-5, SAPO-5 그리고 SAPO-11을 수열합성하여 제조한 다음 XRD, SEM, NH₃TPD와 IR을 통해 물리화확적 특성을 조사하였다. 증기상에서 cyclohexanone oxime의 Beckmann 전이 반응 결과는 oxime의 전화율과 Lactam의 수율에 있어서 SAPO-11가 반응성이 우수하였고, WHSV의 변화에 있어서는 AIPO₄-5와 SAPO-5 경우 WHSV가 증가할수록 전화율과 선택도는 감소하였지만 SAPO-11는 선택도가 증가함을 보였다. 본 대상 반응계인 Beckmann 전이 반응에서는 촉매의 기공 크기보다는 산성도에 더 큰 영향을 받음을 알수 있었다. AIPO₄-5, SAPO-5 AND SAPO-11 which are molecular sieves were synthesized by hydrothermal crystallization. The crystallinity of the prepared catalysts was confirmed by XRD and SEM, and their acidic properties were examined by TPD of NH₃and IR. Catalytic characteristics of the catalysts were tested by vapor phase Beckmann rearrangement of cyclohexanone oxime to caprolactam. The conversion of lactam and yield of lactam increased with acidity of the catalyst. Among the tested catalysts, SAPO-11 was excellent in Beckmann rearrangement reaction. AIPO₄-5 and SAPO-5 showed that conversion of oxime and selectivity of lactam decreased with the increase of WHSV but SAPO-11 showed different tendency in selectivity of lactam, or selectivity of lactam increased with the increase of WHSV. Beckmann rearrangement reaction was affected by acidity than pore size.

市販 生水 및 藥水의 成分에 관한 調査

채영주 이화여자대학교 대학원 1985 硏究論叢 Vol.13 No.-

In order for analysis of the actua'l condition of commercial life water, 10 samples were collected from a supermarket and home delivery company which were investigated for the method of analysis during the period of October 1983 to December 1983. The results were as follows; 1. Non suitable drinking water occupoed in the level 80% of total samples. 2. In non suitable elements, pH showed in the mean 4.8 and occupied in the level 80% of total samples. Three samples were detected both NH_3-N and No_2-N, and Mn was detected higher than standard limit with two samples.

악관절 과두걸림의 보존적 치료에 대한 방사선학적 평가

김영주,이명희,정성창 대한두개하악장애학회 1992 대한두개하악장애학회지 Vol.4 No.1

The authors examined the condylar movement in 28 patients with closed locking of the temporomandibular joint before and after treatment and 33 controls by transcranial radiography. The Treatment adminstered to the patients were noninvasive and conservative therapy such as patient education, home care, reductive manipulation, physical therapy and occlusal splint. The authors obtained the following results. 1. In patient group, the mean amount of condylar translation was 5.07±2.00㎜ in the affected side and was 7.39±3.22㎜ in the unaffected side before treatment, the mean amount of condylar translation in affected side was 12.77±2.75㎜ and in unaffected side was 15.52±2.53㎜ after treatment. And the condylar translation was significantly improved after treatment(P<0.001). 2. In patient group, the ranges of comfortable mouth opening were 27.04±4.12㎜ and maximum mouth opening were 29.96±3.69㎜ before treatment, the ranges of mouth opening were below 40㎜, And the ranges of comfortable mouth opening were 43.86±1.86㎜ and maximum mouth opening were 43.96±1.90㎜ after treatment. And the mouth opening was significantly improved after treatment(P<0.001). 3. In patient group, the mean amount of treatment time was 4.13 ±1.52 months when patients opened above 40㎜. 4. The mean amount of condylar translation was 17.23±2.75㎜ in control group and was 12.77±2.75㎜ in the affected side of patient group after treatment. There was a significant difference between the groups(P<0.001), And in the unaffected side of patient group, the mean amount was 15.52±2.53㎜ after treatment. There was a significant difference between the control group and the unaffected side of patient group(P<0.05). 5. The ranges of comfortable mouth opening were 43.86±1.86㎜ in patient group after treatment and 42.82±4.47㎜ in control group. There was no significant difference between the groups. But the ranges of maximum mouth opening were 43.96±1.90㎜ in patient group after treatment and 46.48±3.85㎜ in control group. There was a significant difference between the groups (P<0.05).

기계부품의 수명향상을 위한 표면개질에 관한 연구

유용주 울산대학교 기계부품 및 소재 특성평가연구센터 1999 연구보고서 Vol.1999 No.-

본 연구는 질화시간, 온도, 가스입력 및 조성이 공구강(SKD11, SKD61)의 질화층 두께, 경도 및 질화물 상형성에 미치는 영향과 질화처리후 글로잉처리가 질화층 상변화에 미치는 영향을 마이크로펄스 플라즈마 장비를 이용하여 연구하였다. 일반적으로 질화층은 두께가 엷은 화합물층과 그 아래에 두께가 비교적 큰 확산층으로 구분되어 관찰 되었다. 질화층에 형성된 상은 처리조건에 따라 다소 달라지나 화합물층에는 γ'(Fe₄N). ε(Fe₂-₃N), 및 Cr1.75V0.25N₂ 등과 같은 질화물만이 검출되었고 확산층에는 ε질화물(Fe₂-₃N)과 (Cr, Fe)7C₃, Fe₃C와 같은 탄화물이 XRD 분석에 의하여 검출 되었다. 질화처리에서 가스조성 중 질소의 양이 증가할수록 화합물층의 두께는 직선적으로 증가되며, 질화층 두께는 가스압력 200Pa일 때 최대가 되었고, 질화온도는 표면경도가 높고 모재의 경도감소를 피할 수 있는 490℃가 최적조건 이었다. 질화층은 포물선형으로 성장되며, 에서 온도 및 재질에 따라 결정되는 상수 k는 490℃, 200Pa에서 SKD11강은 0.04472×10³㎛·hr-½, SKD61강은 0.05367×10³㎛·hr-½이었다. 플라즈마 질화처리한 공구강을 글로잉 처리하면 표면경도는 다소 감소 되나 확산층의 깊이는 증가하며, 이때 화합물층은 (Cr, Fe)7C₃ 및 Fe₃C의 탄화물로 변화되였고 확산층은 상변화가 없었다. The effect of gas composition, pressure, temperature and time on the case thickness, hardness and nitride formation in the surface of tool steels (SKD11 an SKD61) have been studied by micro-pulse plasma technique. Together with the effects of glowing treatment on the phase transformation in the nitrided case of tool steels have also been studied. Typically, external compound sayer and internal diffusion sayer which is much thicker than compound layer was observed in the nitride case of tool steels. The relative amounts and kind of phases formed in the nitrided case changed with the change of nitriding conditions. Generally, only nitride phases such as γ'(Fe₄N). ε(Fe₂-₃N), or Cr1.75V0.25N₂ phases were detected in compound layer, while nitride and carbide phases such as ε-nitride(Fe₂-₃N), (Cr, Fe)7C₃ or Fe₃C have been detected in the duffusion layer by XRD analysis. The thickness of compound layer increased with the increase of nitrogen content in the gas composition. Maximum case thickness was obtained at gas pressure of 200Pa. The optimum nitriding temperature was 490℃ at which temperature high have nitrided case was obtained without the decrease in the hardness of tool steel substrate. The nitrided case was thickened parabolically with nitriding time(t) and thus, the case depth(d) fits well with the typical parabolic equation ; d=k√t. The material constant k for SKD11 and SKD61 nitrided at 490℃(200Pa) were 0.04472×10³㎛·hr-½ and 0.05367×10³㎛·hr-½ respectively. Plasma glowing treatment of nitrided tool steel thickened the diffusion layer of nitrided case and transformed nitride in the compound layer to carbide as ((Cr, Fe)7C₃.

플라즈마 질화법에 의한 SUS316L 스테인레스강의 표면경화에 관한 연구

박정환,김영홍,유용주 울산대학교 1994 공학연구논문집 Vol.25 No.2

본 연구는 SUS316L 스테인레스강을 이용하여 500℃∼600℃의 온도범위에서 NH₃가스의 유량을 0.5∼2.1ℓ/min로 변화시키고, 20∼110분 동안 플라즈마 질화처리하여, 강 표면에 생성된 경화층의 두께와 경도 및 조직을 조사하였다. 반응온도 550℃, NH₃가스의 유량 2.1ℓ/min에서 110분 동안 질화 하였을 경우 생성된 질화층의 두께는 약57㎛로 최대치를 나타내었다. 그리고 질화처리 한 시편을 XRD 분석한 결과 생성된 질화층은 CrN+r-Fe₄N+Fe₃N으로 구성되어 있는 화합물층 이었으며, 확산층은 생성되지 않았고, 생성된 질화층의 경도의 최고치는 약 Hv 1800 이었다. 플라즈마 질화법에 의한 SUS316L 스테인레스 강의 표면경화의 최적조건은 550℃, 2.1ℓ/min. NH₃가스, 110분이었다. A nitrided layer on SUS316L stainless steel by plasma nitrised for back ferrule in one parts of tube fitting has been studied. Specimen was nitrided over 500℃ to 650℃ reaction temperature range with 0.5 to 2.1 ℓ/min. NH₃gas flow rate for 20 to 110 min. The thickness of nitrided layer showed maximum value about 57㎛ at 550℃ reaction temperature and with 2.1ℓ/min. NH₃gas flow rate for 110 min. The result of XRD, nitrided layer was mainly composed of CrN+r-Fe₄N+Fe₃N, but not detected diffusion layer. And also, when NH₃gas flow rate 2.1ℓ/min. , the maximum hardness value of nitrided layer was revealed about Hv 1800 at 550-600℃ reaction temperature range. In this study, the optimum condition of nitrided on SUS316L stainless steel was observed at 550℃ reaction temperature and 2.1ℓ/min. , NH₃gas flow rate for 110 min.

랫트의 鉛中毒에 대한 Butyl hydroxyanisole(BHA)의 影響에 관한 硏究

조필형,안영근,김주영 한국환경독성학회 1991 환경독성보건학회지 Vol.6 No.1

The present study was undertaken to examine the effect of butylhydroxyanisole (BHA) on the lead poisoning in Wister female rats. All experimental rats except normal group were fed with diets formulated by adding BHA in a range of 0.1% to 3.2% and aqueous solution of 1% lead acetate ad libitum through the experimental period. The results obtained are summarized as follows: 1) Lead sedimentation in kidney tissue was decreased with increasing experimental period and BHA level of lead plus BHA-treated groups in comparison with that of lead-treated control group. 2) The weights of lung, spleen and left/right (L/R) kidney were significantly de-creased in comparison with those of lead-treated control group after 2 weeks of experimental period, but no difference was shown with those of normal group. 3) The weights of lung, spleen and L/R kidney were increased in lead-treated control group as compared with normal group after 2 weeks of experimental period, but no difference was shown with increasing experimental period. 4) Water intake was remarkably decreased in lead-treated control group as compared with normal group, but water intake by increasing BHA level of lead plus BHA-treated groups showed no significant difference from that of normal group. 5) These results suggest that BHA is effective for reducing the toxic effect of lead in rats.

랫트의 鉛中毒에 대한 Butyl hydroxyanisole(BHA)의 影響에 관한 硏究

조필형,안영근,김주영 원광대학교 식품약품안전성연구소 1991 食品藥品安全性硏究 Vol.4 No.-

The present study was undertaken to examine the effect of butylhydroxyanisole (BHA) on the lead poisoning in Wister female rats. All experimental rats except normal group were fed with diets formulated by adding BHA in a range of 0.1% to 3.2% and aqueous solution of 1% lead acetate ad libitum through the experimental period. The results obtained are summarized as follows: 1) Lead sedimintation in kidney tissue was decreased with increasing experimintal periok and BHA level of lead plus BHA-treated groups in comparison with that of lead-treated control group. 2) The weights of lung, spleen and left/right(L/R) kidney were significantly decreased in comparison with those of lead-treated control group after 2 weeks of experimintal period, but no difference was shown with those of normal group. 3) The weights of lung, spleen and L/R kidney were increased in liad-treated control group as compared with normal troup after 2 weeks of dxperimental period, but no difference was shown with increasing experimintal period. 4) Water intake was remarkably decreased in lead-treated control group as compared with normal group, but water intake by increasing BAH level of lead plus BHA-treated groups showed no significant difference from toat of normal group. 5) These results suggest that BHA is effective for reducing the toxic effect of lead in rats.

몇가지 치환 피리딘계 화합물의 해리에 미치는 온도와 압력의 영향

황정의,윤영주,김학성 慶北大學校 物理化學硏究所 1983 硏究論文集 Vol.4 No.-

피리딘이나 치환 피리딘 화합물은 염기로서 작용한다. 염기도는 적량적 표시로 염기의 해리 상수나 공액산의 해리 상수로서 나타낼 수 있다. 즉 ◁그림삽입▷(원문을 참조하세요) 반응의 Ka값으로 나타낼 수 있다. 이들 피리딘 치환체의 해리 상수는 상압에서만 알려져 있으나 고압하에서는 전혀 측정된바 없다. 그래서 본 연구에서는 높은 압력하에서 이들 해리 상수를 분광법과 전도도법으로 측정하는 시도를 하였다. 분광법은 흡수 띠가 UV 영역에 있어서 UV 분광법으로 측정했다. 전도도법은 보통 방법으로는 불가능하였고 상압에서의 해리 상수를 알고 있는 물질에 대해서 용액의 전도도를 측정하고, 이 값에서 관여 이온 전도도를 계산하여 해리 상수를 계산하였다. 측정은 m-chloro, m-bromo 및 o-bromopyridine에 대해서 이루어졌으며 양방법에 의한 값들 사이에 약간의 차이가 있었으나 이온 전도도법에 사용한 가정이나 외삽한 값을 이용한 점을 감안할때 비교적 성공적이라고 할 수 있었다. 또 해리반응에 대한 열역학적 데이터를 감안할때 온도나 압력에 따른 변화가 비슷하게 얻어졌고 이들 값을 미루어 보아 해리과정을 추적하는데 도움이 되었다. Pyridine and most of substituted pyridines react as base in aqueous solutions. Strength of their basicities can be represented quantitatively by the dissociation constant of a base or its conjugated acid. For example, the basicity of pyridine can be represented by Ka of the following reaction. ◁그림삽입▷(원문을 참조하세요) The dissociation constants of these substituted pyridines have been reported only under pressure of atmosphere but not high pressure. In this study, we try to measure the dissociation constants of some substituted pyridines under high pressure by the methods of conductance, spectrophotometry. Because the adsorption band exists in UV range, we used UV spectrophotometry. In conductometry we could not apply the general method of conductivity, hence measured the conductivity of the mixed ionic species and then calculated the ionic conductances. From the ionic conductivity of hydrogen ion the dissociation constants (Ka) can be calculated. We measured the dissociation constants of m-chloro, m-bromo and o-bromopyridine. There is a little difference between the dissociation constants from spectrophotometric and conductometric methods. But when we consider the approximated conditions and extrapolated values used in calculating ionic conductance, we could conclude that its difference is insignificant. We obtained the thermodynamic data on the dissociation reactions that showing the effect of the temperature and the pressure on the dissociation constants are similar and we can deduce the mechanism of the dissociation process of some substituted pyridines.

전도도법에 의한 치환 피리딘들의 해리상수 측정과 그의 온도와 압력에 따른 영향

黃正儀,鄭倧在,金學成,尹永炷,朴義煥 慶北大學校 物理化學硏究所 1985 硏究論文集 Vol.6 No.-

Generally, pyridine and most of substituted pyridines act as base in aqueous solutions. The strengths of their basicities can be expressed quantitatively by the dissociation constant of base or its conjugated acid. Generally, the acidity of substituted pyridines can be expressed by K_a of the following reaction. ◁그림삽입▷(원문을 참조하세요) The dissociation constants of these subtituted pyridines have not been reported under high pressure but under atmospheric pressure. In this papers, the dissociation constants of some substituted pyridines were measured under high pressure by the conductometry. From the ionic conductivity of hydrogen ion, the dissociation constants(K_a) were calculated. The K_a values were increased with increasing temperature and were decreased with increasing pressure. The characteristics of dissociation process of some substituted pyridines were deduced from the thermodynamic properties calculated from the dissociation constants.

전도도법에 의한 치환 피리딘들의 해리상수 측정과 그의 온도와 압력에 따른 영향

黃正儀,鄭倧在,金學成,尹永炷,朴義煥 慶北大學校 1984 論文集 Vol.38 No.-

Generally, pyridine and most of substituted pyridines act as base in aqueous solutions. The strengths of their basicities can be expressed quantitatively by the dissociation constant of base or its conjugated acid. Generally, the acidity of substituted pyridines can be expressed by K_a of the following reaction. ◁그림 삽입▷ (원문을 참조하세요) The dissociation constants of these subtituted pyridines have not been reported under high pressure but under atmospheric pressure. In this papers, the dissociation constants of some substituted pyridines were measured under high pressure by the conductometry. From the ionic conductivity of hydrogen ion, the dissociation constants (K_a) were calculated. The K_a values were increased with increasing temperature and were decreased with increasing presure. The charateristics of dissociation process of some substituted pyridines were deduced from the thermodynamic properties calculated from the dissociation constants.