Synthesis of Aluminum Sulfate from Kaolin and Its Thermal Decomposition

박성수,강효경,박홍채,박희찬,Park, Seong-Su,Gang, Hyo-Gyeong,Park, Hong-Chae,Park, Hui-Chan Materials Research Society of Korea 1998 한국재료학회지 Vol.8 No.2

카올린을 용해시킨 황산용액을 에탄올에 주입함으로써 알루미늄황산염의 침전물, $AI_{2}(SO_{4})_{3}\cdot18H_{2}O$을 제조하고, 그것의 열분해거동을 검토하였다. 합성된 고순도의 침전물은 약 $2\mu\textrm{m}$크기의 판상형태의 입자들로 구성되어져 있었다. 에탄올속으로 카올린을 용해시킨 황산용액의 주입속도를 증가시킴에 따라서 생성된 침전물의 결정사 크기는 감소하였다. 침전물의 탄수 및 탄황산에 대한 겉보기 활성화에너지는 각각 $11.9Kcal mol^{-1}$ 과 $48.2kcal mol^{-1}$ 이었다. Aluminum sulfate, $AI_{2}(SO_4)_3\cdot18H_2O$ was prepared by adding of kaolin-dissolved sulphuric acid into ethanol and its thermal decomposition behavior was discussed. As-synthesized high purity precipitate particles were platelike shapes of $2\mu\textrm{m}$ size. With increasing drop rate of leach liquor into ethanol, the crystallite sizes of the precipitate decreased. The apparent activation energies for dehydration and sulfate decomposition of the precipitate were $11.9Kcal mol^{-1}$ and $48.2kcal mol^{-1}$ respectively.

고체 전지용 Li$_2$O-2SiO$_2$-xCuO 계 전도성 유리의 제조에 마이크로파 에너지의 이용 및 특성 비교

박성수,김경태,이상은,김병찬,박진,박희찬,Park, Seong-Soo,Kim, Kyoung-Tae,Lee, Sang-Eun,Kim, Byoung Chan,Park, Jin,Park, Hee-Chan 한국결정성장학회 2000 한국결정성장학회지 Vol.10 No.3

마이크로파 열처리공정이 여러 가지 CuO 조성을 가진 $Li_2O-2SiO_2$-xCuO 유리의 전기전도도와 결정화 거동에 미치는 영향을 조사하기 위하여 재래식 열처리 공정과 비교하였다. 각기 재래식과 마이크로파 가열법으로 열처리하였을 때, 시편들의 전기전도도는 CuO 함량이 증가할수록 증가하였고, 각 조성에서 마이크로파로 열처리된 시편이 재래식으로 열처리된 시편에 비하여 높은 전기전도도를 보였다. 또한 X-선 회절 실험 결과, 마이크로파 열처리는 $Li_2Si_2O_5$ , $Li_2Cu_5(Si_2O_7)_2$및 $Li_2Cu_O_3$상의 결정화 정도를 향상시켜주었다. $Li_2O-2SiO_2$-1.3CuO(30 mo1% CuO) 유리를 $500^{\circ}C$에서 30분 동안 재래식과 마이크로파로 열처리한 후 상온에서 측정한 시편들의 전기전도도는 각기 $0.11{\times}10^{-4}(\Omega \textrm {cm})^{-1}$과 $0.68{\times}10^{-4}(\Omega \textrm {cm})^{-1}$이었다. 마이크로파 에너지는 시편들의 결정화를 향상시키고, 전기전도도 값도 증가시킨다고 판단되었다. Effect of microwave heat-treatment processing on the electrical conductivity and crystallization behavior for the $Li_2O-2SiO_2$-xCuO glasses with various CuO contents was compared with that of conventional heat-treatment processing. The electrical conductivities of samples heat-treated at $500^{\circ}C$ by different heat-treatment processing were increased with increasing CuO content and higher electrical conductivities were obtained from microwave heat-treated samples. From the result of XRD analyses, microwave heat-treatment processing enhanced the degree of crystallization in the formation of $Li_2Si_2O_5, Li_2Cu_5$($Si_2O_7)_2$, and $Li_2Cu_2O_3$ crystalline phases. The electrical conductivities of $Li_2O-2SiO_2$-1.3CuO (30 mol% CuO) glass heat-treated at $500^{\circ}C$ for 30 min under conventional and microwave heat-treatment processing were $0.11{\times}10^{-4}(\Omega \textrm {cm})^{-1}$ and $0.68{\times}10^{-4}(\Omega \textrm {cm})^{-1}$ at room temperature, respectively. It was speculated that microwave energy enhanced the degree of crystallization and increased electrical conductivity in the samples.

마이크로파와 재래식 열원을 이용한 고체 전지용 Li$_2$O-2SiO$_2$계 전도성 유리의 제조 및 특성에 관한 연구

박성수,김경태,김병찬,박진,박희찬,Park, Seong-Soo,Kim, Kyoung-Tae,Kim, Byoung-Chan,Park, Jin,Park, Hee-Chan 한국결정성장학회 2000 한국결정성장학회지 Vol.10 No.1

재래식 및 마이크로파 가열법으로 열처리된 $Li_2O_3-SiO_2$계 글라스의 핵 생성 및 결정화 거동을 열분석법(DTA), X-선 회절(XRD), 광학 현미경(OM) 및 전기 전도도의 측정으로 비교 조사하였다. 재래식 및 마이크로피로 열처리된 시료들의 조핵 온도와 최대 핵 생성 온도는 동일하게 각각 460~$500^{\circ}C$와 $580^{\circ}C$이었다. 한편, 재래식에 비하여 마이크로파로 열처리된 시료에서는 부피 핵 생성이 일어나려는 경향이 컸다. 재래식 및 마이크로파로 열처리된 시편들에서 결정의 성장 속도는 결정화 열처리 온도에 비례하여 증가하였지만, 마이크로파 열처리의 경우는 부피 핵 생성 경향 및 물질 확산 효과의 증대에 기인하여 결정 성장을 재래식 보다 빠르게 진행되었다. 재래식 및 마이크로파로 열처리된 시편들의 전기 전도도 값은 각각 1.337~2.299와 0.281~$0.911{\times}10^{-7}\Omega {\textrm}{cm}^{-1}$이었다. The behavior of nucleation and crystallization in the $Li_2O_3-SiO_2$ glass heat-treated at different condition under the conventional and microwave processing was studied by differential thermal analysis (DTA), X-ray diffractometry (XRD), optical microscopy (OM), and electrical conductivity measurement. Nucleation temperature and temperature of maximum nucleation rate in both conventionally and microwave heat-treated samples were 460~$500^{\circ}C$ and $580^{\circ}C$, respectively. It was expected that the probability for bulk crystallization increased in microwave heat-treated sample, compared to conventionally heat-treated one. Degree of crystallization increased with increasing crystallization temperature in both conventionally and microwave heat-treated samples. However, pattern of crystallization growth under microwave processing appeared to be quite different from that under the conventional one due to its internal or volumetric heating. Electrical conductivity of conventionally and microwave heat-treated samples were 1.337~2.299, 0.281~~$0.911{\times}10^{-7}\Omega {\textrm}{cm}^{-1}$, respectively.

Flux법에 의한 알파 알루미나 판상체의 마이크로파 합성

박성수,김준호,김성완,이성환,박재현,박희찬,Park, Seong-Soo,Kim, Jun-Ho,Kim, Sung-Wan,Lee, Sung-Hwan,Park, Jae-Hyun,Park, Hee-Chan 한국세라믹학회 2002 한국세라믹학회지 Vol.39 No.5

Flux법과 마이크로파 가열법으로 $Al_2(SO_4)_3+2Na_2SO_4$ 및 ${\gamma}-Al_2O_3+2Na_2SO_4$ 분말혼합물로부터 ${\alpha}-Al_2O_3$ 판상체(platelets)를 합성하였다. ${\alpha}-Al_2O_3$ 판상체 형성에 미치는 마이크로파의 영향을 조사하기 위하여 DTA-TG, XRD 및 SEM을 이용하였다. $Al_2(SO_4)_3+2Na_2SO_4$ 혼합물의 경우, 마이크로파로 가열된 시료는 재래식으로 가열된 시료에 비하여 입자의 크기가 작고 응집체로 구성된 ${\alpha}-Al_2O_3$ 판상체로 나타났다. ${\gamma}-Al_2O_3+2Na_2SO_4$ 혼합물의 경우, 마이크로파 가열에 의한 ${\alpha}-Al_2O_3$ 판상체 형성온도는 재래식 가열에 의한 형성온도 보다 낮았다. 또한 마이크로파로 가열된 시료의 형상은 재래식으로 가열된 시료의 형상과 유사하였다. 그러나 마이크로파로 가열된 시료는 재래식으로 가열된 시료에 비하여 입자의 크기가 작았다. ${\alpha}-Al_2O_3$ platelets were synthesized by microwave heating the two different powder mixtures of $Al_2(SO_4)_3+2Na_2SO_4$ and ${\gamma}-Al_2O_3+2Na_2SO_4$ using flux method. DTA-TG, XRD and SEM were used to investigate the effect of microwave on the formation of ${\alpha}-Al_2O_3$ platelets. In the case of the mixture of $Al_2(SO_4)_3+2Na_2SO_4$, the microwave heated sample was ${\alpha}-Al_2O_3$ platelets composed of aggregates with smaller particle size compared to the conventionally heated sample. In the case of the mixture of ${\gamma}-Al_2O_3+2Na_2SO_4$, the temperature to form ${\alpha}-Al_2O_3$ platelets by the microwave heating was lower than that by the conventional heating and the morphology of the microwave heated sample was similar to that of the conventionally heated sample except that the microwave heated sample had smaller particle size compared to the conventionally heated sample.

$\textrm{CuO}-\textrm{Bi}_{2}\textrm{O}_3-\textrm{V}_2\textrm{O}_5$계 글라스에서 조성 변화에 따른 전기 전도도의 특성

박성수,정동진,이현,박찬영,민성기,박희찬,Park, S.S.,Jeong, D.J.,Lee, H.,Park, C.Y.,Min, S.K.,Park, H.C. 한국재료학회 1998 한국재료학회지 Vol.8 No.12

CuO-Bi$_2$O$_3$-V$_2$O$_{5}$ 삼성분계 유리 시편을 열처리 시간과 온도를 달리하여 열처리 하였을 때, 열처리된 시편의 결정화 거동 및 전기전도도 특성을 조사하였다. 여러 조성의 시편들 가운데 31CuO-14Bi$_2$O$_3$-55V$_2$O$_{5}$ (mol%)의 조성을 가진 시편이 상온에서 가장 높은 전기 전도도를 나타내었고, 이 시편을 358$^{\circ}C$에서 8h동안 열처리하여 결정화 시켰을 때, 고체 전해질용으로서는 매우 높은 전기 전도도 값인 2.67$\times$$10^{-2}$ $\Omega$$^{-1}$ $cm^{-1}$ /를 나타내었다. 유리상의 시편을 열처리 하였을 때 열처리된 시편은 BiVO$_4$ 및 CuvVO$_3$결정의 형성과 성장이 이루어지면서 전기 전도도가 비열처리 시편에 비하여 $10^3$-$10^4$배 크기로 증가하였다. The crystallization behaviors and electrical conductivities of the glasses heat-treated at various times and temperatures in the CuO-Bi$_2$O$_3$-V$_2$O$_{5}$ glass system were investigated. Among glass samples with various compositions, the highest conductivity obtained in the 31CuO-14Bi$_2$O$_3$-55V$_2$O$_{5}$ (mol%) glass sample. The 31CuO-14Bi$_2$O$_3$-55V$_2$O$_{5}$ (mol%) glass sample crystallized by heat treatment at 358$^{\circ}C$ for 8h had 2.67$\times$10$^{-2}$ $\Omega$$^{-1}$ $cm^{-1}$ /, which was much high value as a solid electrolyte. Compared to the glass sample, the heat- treated glass sample was increased in conductivity by an order of 10$^3$-10$^4$due to the formation and growth of BiVO$_4$ and CuVO$_3$crystals.

치과용 소형 C자형 투시장치를 이용한 하악 연조직에 위치한 부러진 기구의 제거: 증례보고

박성수,양훈주,황순정,Park, Sung-Soo,Yang, Hoon-Joo,Hwang, Soon-Jung 대한악안면성형재건외과학회 2010 Maxillofacial Plastic Reconstructive Surgery Vol.32 No.6

Intraoperative breakage of instruments can be occurred unexpectedly. To prevent damage of neighboring important anatomic structures and consequent complications, broken instruments should be removed as soon as possible. There have been several methods to remove broken instruments. One of them is the Carm fluoroscopy which is commonly used for locating metal foreign bodies. However, its application for removal of broken instruments in the oral and maxillofacial area is not common. In our experiences with the removal of two broken instruments in mandibular area, the newly developed dental mini C-arm was used to find broken instrument in soft tissue, because it gives real-time in situ information for the intraoperative location. We report two cases with broken instruments, a broken dental needle in the pterygomandibular space and a broken straight bur in the mandibular angle area. They were identified and could be removed safely using a dental mini C-arm.

보통 대통령 시대의 대학상 조각

박성수,Park, Seong-Su 한국대학교육협의회 1988 大學敎育 Vol.32 No.-

지능형 브레이커의 자동타격 메카니즘 분석

박성수,노대경,이대희,이근호,강영기,조재상,장주섭,Park, Sung-Su,Noh, Dae-Kyung,Lee, Dae-Hee,Lee, Geun-Ho,Kang, Young-Ky,Cho, Jae-Sang,Jang, Joo-sup 한국시뮬레이션학회 2016 한국시뮬레이션학회 논문지 Vol.25 No.4

This study aims to identify the core technology for the automatic impact of the auto-sensing breaker that is one of the construction machinery which do not have a notable development success case yet in Korea. The study has been carried out as follows. Firstly, an analysis model was developed after determining the interconnection of pressure receiving area, opening area and port. And then, a simulation of situation that hard rock and soft rock are mixed was carried out to verify if it is possible to switch between long impact mode and short impact mode continuously. Lastly, the dynamic behavior of automatic control valve induced by the change of impact mode was analyzed based on the analysis result to decipher the core principle of automatic impact control. 본 연구는 국내에서는 현재 개발 성공사례가 없는 건설 장비 중 하나인 지능형 브레이커의 자동타격조절 핵심기술을 파악하는 것을 목적으로 하고 있다. 연구진행은 다음과 같은 절차로 진행된다. 우선 수압면적과 개도면적, 포트의 연결 관계를 파악하여 해석모델을 개발한다. 그리고 해석모델에 경암과 연암을 오가는 상황을 모사하여 연속적으로 장타모드와 단타모드의 가변이 가능한지 검증한다. 마지막으로 해석결과로부터 타격모드가 가변될 때 발생하는 자동제어밸브의 동적거동을 분석하여, 자동타격조절의 핵심원리를 파악한다.

다발성 조기위암의 임상적 고찰

박성수,류근원,송태진,목영재,김종석,김승주,Park Sung Soo,Ryu Keun Won,Song Tae Jin,Mok Young Jae,Kim Chong Suk,kim Seung Joo 대한위암학회 2001 대한위암학회지 Vol.1 No.3

Purpose: Multiple early gastric cancers were found in $6.9\∼11.7\%$ of patients with early gastric cancer. The goal of this study was to clarify the clinicopathologic features of and to investigate treatment strategy for multiple early gastric cancer. Materials and Methods: Of 967 patients with an gastric adenocarcinoma who were treated by surgical resection during the period of $1993\∼1998$ at the Department of Surgery, Korea University College of Medicine, 267 patients had early gastric cancer. A retrospective analysis of the clinicopathologic differences between the main and the accessory lesions in multiple early gastric cancer was carried out. A comparative analysis was also conducted between solitary early gastric cancer and multiple early gastric cancer. Results: Of 267 patients with early gastric cancer, multiple early gastric cancers were found in 12 patients ($4.5\%$), including 10 men and 2 women. Eleven patients with multiple early gastric cancer had one accessory lesion and 1 patient had 2 accessory lesions. Of the 13 accessory lesions, 7 ($53.8\%$) were located in the same region as the main lesion. The most frequent combination of macroscopic types for the main lesion and the accessory lesion were depressed and depressed types (6 cases, $46.1\%$). The most frequent histologic type of main lesion was a well differentiated adenocarcinoma in 7 ($58.3\%$) of the 12 cases; the accessory lesion was also well differentiated in 4 of those 7 cases. Of the 13 accessory lesions, 4 ($30.8\%$) had been overlooked preoperatively; most of them were located in the lower third of the stomach and were IIb or IIc type and measured less than 1 cm in diameter. Lymph node metastasis was detected in 1 patient ($8.3\%$). The clinicopathologic features of multiple early gastric cancer were not different from those of solitary early gastric cancer. Conclusion: In multiple early gastric cancer, the main and the accessory lesions showed similar differentiation, and lymph node metastasis was less frequent than in solitary early gastric cancer. Therefore, limited procedures, including endoscopic mucosal resection, may be indicated if each lesion of the multiple early gastric cancer fits the criteria for treatment strategy.

연구논문 - 촉매 : 산화납 촉매 상에서 메탄의 Oxidative Coupling 반응

박성수,김상채,선우창신,유의연 ( S . S . Park,S . C . Kim,C . S . Sunwoo,E . Y . Yu ) 한국공업화학회 1992 한국공업화학회 연구논문 초록집 Vol.1990 No.3