Wire Saw 슬러리로부터 Si와 SiC의 선택적 회수

한승열,이종대,전진혁,박노국,이태진,류시옥 嶺南大學校 工業技術硏究所 2004 工業技術硏究所論文集 Vol.32 No.1

This study was focused on the recovery of Si and SiC from wire saw slurry in wire saw slicing process. In order to separate Si and SiC from wire saw slurry, alkali dissolution method was used and then Na₂O showed superior dissolution property of Si. At this time, SiC was separated as powder from alkali aqueous solution. Si was dissolved as a liquid in alkali aqueous solution. After removing SiC powder, the powder was obtained by drying alkali aqueous solution and then it's XRD analysis showed that it was the water glass (Na₂SiO₃).

Wire Saw 슬러리로부터 Si, SiC 분리 및 제올라이트 합성에 대한 연구

한승열,이종대,박노국,이태진,류시옥 한국공업화학회 2004 응용화학 Vol.8 No.1

This study was focused on the separation of Si and from Wire Saw Slurry in Wire Saw Slicing process and synthesis of zeolite by mixing with water glass obtained from its process and Alumina. In order to separate Si and SiC from Wire Saw Slurry, Alkai disslution was used and then Na₂O showed superior dissoluble property of Si. At this time, SiC was separated as powder from Alkali apueous solution. Si was dissolved as a liquid in Alkali aqueous solution. After removing SiC powder, the powder formed was obtained from drying. Alkali aqueous solution and then it was the water glass (Na₂SiO₃)confirmed by XRD analysis. Water glass (Na₂SiO₃) and Alumina mixed with pure water made as a synthesis of zeolite through the crystallization by aging and hydrothermal reaction. The manufactured zeolite was Sodium Aluminum Silicate Hydrate confirmed by XRD analysis.

2.5% Pentothal sodium 전처치가 Propofol 정주시 발생되는 통증에 미치는 효과

옥시영,김순임,김선종 순천향대학교 교수학습개발센터 2004 Journal of Soonchunhyang Medical Science Vol.10 No.3

Background: propofol has a high incidence of pain with intravenous injection, and many different methods have been used to minimize the incidence and severity of this pain. In this study, we have compared the effect of saline pretreatment with that of 2.5% pentothal 50 mg pretreatment of propofol injection pain. Methods: Sixty two patients scheduled for general anesthesia were randomly divided into two groups. each patient received one of the pretreatment drugs via 18 g angiocatheter inserted in the antecubital fossa. Control group (n=31)received 2 ml of 0.9% saline pretreatment, 2.5% pentothal group (n=31) received 50 mg of pentothal pretreatment followed intravenous injection of 2 mg/kg of propofol at a rate of 1 ml/sec. After 50 mg of propofol were injected, patients were assessed for pain score. The severity of pain was classified as 0, 1, 2, 3 (none, mild, moderate, severe) by one observer. Results: The severity of pain were significantly reduced in 2.5% pentothal group compared with ontrol group for intravenous injection fo propofol (p<0.05) but incidence is similar. Conclusions: 2.5% pentothal 2 ml (50 mg) pretreatment could significantly reduce the sever the severity of pain for intravenous injection of propofol.

Lidocaine과 Pentotal 전투여가 Propofol 정주 시 발생되는 혈관통에 미치는 영향

옥시영,김순임,김선종 순천향대학교 교수학습개발센터 2004 Journal of Soonchunhyang Medical Science Vol.10 No.3

Background: Propofol is a good induction agent. But it has a disadvantage of pain on intravenous injection. Pretreatment of lidocaine or pentothal have been reported to reduce pain on injection. Thus we have evaluated the quantity and quality of analgesic effect of lidocaine and pentothal. Methods: Ninety three patients scheduled for general anesthesia were randomly divided into three groups. Each patient received one of the pretreatment drugs via 18 G angiocatheter inserted in the antecubital fossa. Control group (n=31) received 2 ml normal saline and lidocaine group (n=31) received 40 mg (2%, 2ml) and petothal group (n=31) received 50 mg (2.5%, 2 ml) followed intravenous injection of 2 mg/kg of propofol at a rate of 1 ml/sec.After 50 mg of propofol were injected, patients were assessed for pain score. The severity of pain was classified as 0,1, 2, 3 (none, mild, moderate, severe) by one observer. Results: The severity and incidence of pain were significantly reduced in lidocaine group and pentothal group compared with control group for intravenous injection of propofol (P<0.05). And the incidence of pain in lidocaine group and pentothal group is similar but severity of pain is more reduced in lidocaine group Conclusions: Lidocaine 40 mg or pentohal 50 mg pretreatment to induction by propofol revealed a good analgesic effect for propofol injection pain. And lidocaine is more effective for iv propofol injection pain.

압박띠와 Lidocaine 전처치 및 Pentothal 전처치를 이용한 Propfol 정주통의 예방효과

옥시영,김순임,김선종 순천향대학교 교수학습개발센터 2004 Journal of Soonchunhyang Medical Science Vol.10 No.3

Background: Pain on injection of propofol is a common problem, the cause of which remains unknown, We evaluated the effect of a tourniquet with intravenous lidocaine and pentothal pretreatments, to decrease the incidence and intensity of pain during intravenous propofol injection. Methods: One hundred fifty five patients scheduled for general anesthesia were randomly divided into three groups. Each patient received one of the pretreatment drugs via 18 G angiocatheter inserted in the antecubital fossa. Control group (CG) (n=31) recived 2 ml normal saline and lidocaine group (LG) (n=31) received 40 mg (2%, 2 ml) and pentothal group (PG) (n=31) received 50 mg (2.5%, 2 ml) and lidocaine tourniquet group (LTG) (n=31) received 40 m g(2%, 2ml) under tourniquest 1 minute inflated and pentothal tourniquet group(PTG) (n=31) received 50 mg (2.5%, 2 ml) under tourniquet 1 minute inflated followed intravenous injection of 2 mg/kg of propofol at a rate of 1 ml/sec. after 50 mg of proplfol were injected, patients were assessed for pain score. The severity of pain was classified as 0, 1, 2, 3 (none, mild, moderate, severe) by one observer. Results: The severity and incidence of pain were significantly reduced in lidocaine group and pentothal group compared with control group for intravenous injection of propofol (P<0.05). But effect of tourniquet is minimal. And the quantity and quality of analgesic effect of lidocaine and petothal on propofol iv injection is similar. Conclusions: Lidocaine 40 mg or pentothal 50 mg pretreatment to induction by propofol revealed a good analgesic effect for propofol injection pain. But effect of tourniquest is minimal.

좌심실내 혈류 전파 속도에 관한 연구

최시완,정진옥,강승식,성인환,박종훈 충남대학교 의과대학 지역사회의학연구소 1995 충남의대잡지 Vol.22 No.1

Background : Noninvasive attemps to identify left ventricular relaxation have been hampered because relaxation rate, left atrial filling pressure, and chamber compliance are the major determinants of peak early velocity and filling rate. This study was perfomed to evaluate the relation between the velocity of flow propagation and left ventricular relaxation by using pulsed doppler echocardiography to analize flow propagation in the left ventricle. Method : By using pulsed Doppler echocardiography, the velocity of left ventricular flow propagation was measured from the distance and time difference of flow wave along the long axis propagation of left ventricular inflow during early filling in normal subjects (n=30), and M-mode echocardiographic data were obtained to evaluate mitral annulus long axis movement (mitral annulus relaxation rate) which represents left ventricular relaxation. Results : the peak early velocity was not related to mitral annulus relaxation rate, but, the velocity of flow propagation was related to mitral annulus relaxarate (P<0.005) in normal subjects. Conclusion : the velocity of flow propagation during early filling seems to be highly dependent on the mitral annulus relaxation rate and could be an important noninvasive tool in studying diastolic function.

충격관을 이용한 메탄의 연소반응 연구

류시옥,이승철,송병수,황순묵 영남대학교 공업기술연구소 2001 工業技術硏究所論文集 Vol.29 No.1

Study on the ignition of methane fuel system highly diluted with argon was carried out in the temperature range of 1515∼1905K behind a reflected shock wave to investigate the rate coefficients for the reaction CH3+O2=CH3O+O. Ignition delay times were measured by monitoring the light absorption by methyl radical at ca. 214nm and pressure profiles. Computer modeling study of methane oxidation was also performed using a GRI_MECH, version 2.11 mechanism for sensitivity analysis and calculation of ignition delay times. The correlation of τp with the maximum heat release rate (dq/dt)max in the reaction zone was also investigated.

한·일 국민학교 자연교과서 삽화 비교

박시현,우종옥 한국교원대학교 과학교육연구소 1994 청람과학교육연구논총 Vol.4 No.1

In this study, with the problem of "What is the desirable illustrations?", the problem points of the existing textbooks were analyzed, and the opinions of experts concerning desirable illustrations were examined through questionaire survey, and by developing 'Analysis Frameworkof Illustrations', and Korean-Japanese 'science' textbooks were analyzed and compared with. The conclusions for the direction of korean 'science' textbooks are summarized as follows: 1) The numbers of korean illustrations should be more about two than one of per one page of the existing textbooks. 2) The korean illustrations for the 6th grade should be more largely inserted. 3) The more econmic space utilizing measure should be groped for looking at from the such side. 4) Though the kinds of Korean illustrations are mostly composed of photographs, pictures, illustrations, cartoons, etc. should be positively utilized, and the shapes of photographs should be diversified by such as square, round shape, omissions of background and others. 5) The distribution of players by sex should be considered envenly for male and female from the ascendency of male (1.5:1). 6) It was found that it is desirable for the formation of role of illustrations of 20% for motive inducement, 45% for guidance for experimentation, 30% for presentation of data, and 5% for presentation of the results of experimentation. 7) The illustrations for guidance for experimentation should present important stages of experimentation process regardless the number of illustration. 8) It would be advantageous for motive induction to find the subject matters as possible as from the children's close actual life. 9) It is necessary to induce more freely method in utilizing printing plate for inserting illustrations. 10) It is the result of research that the existing Korean textbooks are not suitable in inducing interest, and the positive strategy to induce interest is demanded. 11) It is required to select their location freely in accordance with the content regardless the. 12) In order to develop such illustrations, it is required to cultivate expert illustrators, and more economic investment is required for development of illustrations, The emphasis matters of revision of the 6th educational process of 'Inducement of study motive and emphasis on interest' is the change of presenting form and method of illustrations, which is expected to be rewarded with much good fruits.

안와내벽의 단독외향골절에서 골절정도와 안구함몰정도와의 관계

진홍률,신시옥,추무진,최영석,양상권,김종욱 대한이비인후과학회 1998 대한이비인후과학회지 두경부외과학 Vol.41 No.5

SO₂로부터 원소 황 회수를 위한 Ce_(1-x)Zr_(x)O₂ 촉매반응연구

김봉석,이종대,박노국,류시옥,이태진,김재창 한국화학공학회 2003 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.41 No.5

Ce_(1-x)Zr_(x)O₂ 촉매상에서 CO에 의한 SO₂의 촉매환원으로부터 원소 황 회수 반응에 대하여 연구하였다. Ce_(1-x)Zr_(x)O₂ 촉매는 Ce/Zr 조성비를 x=1, 0.8, 0.5, 0.2, 0과 같이 조절하여 제조하였으며 반응온도(400-450℃), 공간속도(10,000-70,000 h^(-1)) 변화에 따른 SO₂전화율과 원소 황(S)선택도를 조사하였다. Ce_(1-x)Zr_(x)O₂촉매의 최적반응온도는 425℃ 이었으며 공간속도 50,000 h^(-1)에서 Ce_(0.8)Zr_(0.2)O₂와 Ce_(0.5)Zr_(0.5)O₂ 촉매의 SO₂ 전환율이 93%, 원소 황 선택도 98%로 CeO₂, Ce_(0.2)Zr_(0.8)O₂ 촉매보다 반응성이 높았다. Ce_(1-x)Zr_(x)O₂촉매에 Zr의 첨가량이 증가할수록 CeO₂의 환원률이 증가되었으며, 이러한 결과는 산소 저장성이 우수한 CeO₂에 Zr를 첨가함으로써 산소이동성이 증가되었기 때문인 것으로 판단된다. 본 연구에서 Zr의 첨가로부터 Ce-based 촉매의 격자산소 환원과 비어있는 격자산소 자리의 재산화에 영향을 주어 redox 반응특성을 개선할 수 있음을 확인하였다. The catalytic reduction of SO₂ to elemental sulfur with CO over Ce_(1-x)Zr_(x)O₂ was studied. The Ce_(10x)Zr_(x)O2 catalysts were prepared by changing the Ce/Zr mole ratio(x=1, 0.8, 0.2, 0). The reactivity of Ce_(1-x)Zr_(x)O₂ in accordance with experimental conditions, such as reaction temperature(400-450??), space velocity (GHSV: 10,000-70,000 h^(-1)) were investigated. The conversion of SO2 and the selectivity to elemental sulfur in the recovery of elemental sulfur from SO2 using Ce_(0.8)Zr_(0.4)O₂ and Ce_(0.5)Zr_(0.5)O₂ catalysts were respectively about 93% and 98% at temperature about 425 ??, which were superior to other catalysts. It seems that the reactivity is influenced by the Ce/Zr mole ratio. From these results, it was concluded that the oxygen mobility of catalysis was increased with inserting the Zr. Because the reduction of lattice oxygen and reoxidation of Ce-based catalysts was improved by the adding Zr, it is possible to improve the redox characteristic.