Improved Adhesion of Metal Electrode Layer on Si₃N₄ Substrate through an All-Wet Process

Kim, Danbi,Eom, Nu Si A,Kim, Jiwon,Lee, Kyu Hyoung,Park, Sung Heum,Lee, Ju Ho,Chao, Yong-Ho,Lim, Jae-Hong Electrochemical Society 2019 ECS journal of solid state science and technology Vol.8 No.2

<P>Electroless deposition requires preliminary surface treatment to effectively adsorb a metal electrode layer onto a ceramic substrate. Herein, a simple surface treatment using an all-wet process was performed to achieve adhesion stability between a Si<SUB>3</SUB>N<SUB>4</SUB> substrate and Ni film. The method involved deposition of an interfacial Pd-TiO<SUB>2</SUB> buffer between the two layers. Surface pretreatment via silanization was initially performed to improve surface wettability, thereby enhancing uniform deposition of Pd-TiO<SUB>2</SUB>. Subsequently, a thin Ni layer was directly deposited onto the Pd-TiO<SUB>2</SUB> layer without necessitating sensitization or activation. The synthesized Ni/Pd-TiO<SUB>2</SUB>/Si<SUB>3</SUB>N<SUB>4</SUB> heat sink exhibited excellent adhesion property in the cross-hatch, scratch, and thermal shock tests. The mechanism of adhesion enhancement involved chemical bonding of Pd-TiO<SUB>2</SUB> with the self-assembled monolayer on the substrate and reduced internal stress due to removal of residual hydrogen between the layers of the heat sink. Thus, the fabricated heat sink has a promising application in electronic devices operated at high temperatures.</P>

배기 저항의 능동제어를 통한 배기 시스템의 최적화에 관한 연구

임경빈,류봉조,이규섭,김상덕,송시영,이상훈 한밭대학교 생산기반기술연구소 2002 생산기반기술연구소 논문집 Vol.2 No.1

Automobile exhaust system has difficulty in concentrating contrary technology, which has diminishing effect of maximum exhaust noises and mininum exhaust pressure for output efficiency improvement into on system. This thesis has the purpose in management of basis study for silence and output efficiency improvement which can be satisfy low noises and low exhaust pressure at the same time through maximizing engine efficiency dealing with activity as the condition of engine controlling exhaust impedance actively. In this thesis, we obtained positive result by making experiment high efficiency exhaust induced shaped silencer in order to satisfy contrary matters which device the improvement of engine efficiency and low perception of exhaust noises at the same time. That is, we proved that it has more excellent in low perceiving noises of exhaust system and output improving efficiency than existing muffler by active controlling the exhaust impedance.

전립선암에 대한 초음파 영상유도 방사선치료의 Setup 오차 분석을 통한 재현성 평가

박성용,임승규,시명근,이지해,김종열,조은주,Park, Sung Yong,Lim, Seung Kyu,Si, Myoung Geun,Lee, Ji Hae,Kim, Jong Yeol,Cho, Eun Joo 대한방사선치료학회 2017 대한방사선치료학회지 Vol.29 No.2

목 적: 전립선암 환자에 대한 비침습적이고 피폭선량에 대한 부담이 없는 초음파를 이용한 영상유도방사선치료의 Setup 오차 분석을 통해 치료의 재현성을 평가해 보고자 한다. 대상 및 방법: 치료가 종료된 전립선암 환자 26명의 1,105영상에 대하여 앞-뒤(anterior-posterior, AP), 좌-우(right-left, RL), 위-아래(superior-inferior, SI) 방향의 Setup 오차에 대해 평균, 표준편차와 3D-error을 분석하였다. 또한 오차범위 0-1 mm, 1-3 mm, 3-5 mm, 5 mm 이상에 대한 각 오차 빈도수(frequency, %) 분석을 통하여 AP, RL, SI 방향에 대한 방향성을 확인 하였다. 결 과: Setup 오차는 AP, RL, SI 방향에 대하여 평균과 표준편차는 $1.87{\pm}1.36mm$, $1.73{\pm}1.22mm$, $2.01{\pm}1.40mm$였다. 3D-error는 평균 $3.63{\pm}1.63mm$였다. 각 방향에 대한 Setup 오차값의 빈도(frequency, %)는 AP 방향에 대한 오차범위 0-1 mm에서 29 %, 1-3 mm에서 50.2 %, 3-5 mm에서 19.6 %, 5 mm 이상에서 1.3 %였다. RL 방향에 대하여 오차범위 0-1 mm에서 31.3 %, 1-3 mm에서는 52.5 %, 3-5 mm에서는 15.8 %, 5 mm 이상에서 0.5 %였다. 마지막으로 SI 방향에 대한 오차범위 0-1 mm에서 26.3 %, 1-3 mm에서 50.2 %, 3-5 mm에서 22.4 %, 5 mm 이상에서 1.1 %였다. 결 론: Setup error는 SI 방향에서 $2.01{\pm}1.40mm$로 가장 컸으며 오차 빈도는 모든 방향에서 50 % 이상 오차 범위 1-3 mm에 들어온 것으로 확인되었다. $Clarity^{TM}$ Auto scan을 이용한 초음파영상유도 방사선치료는 치료 전에 방광의 전처치 상태, target의 구조 등을 관찰이 가능하고, 치료 중 target의 움직임을 실시간으로 monitoring하여 빠른 repositioning이 가능하다. 결과적으로 초음파를 이용한 실시간 영상유도방사선치료는 치료의 재현성을 높일 수 있을 것으로 사료된다. Purpose: To evaluate the reproducibility of image-guided radiotherapy using ultrasonography which is non-invasive, without radiation exposure for prostate cancer patients. Materials and Methods: We analyzed the setup variation of 1,105 images for 26 prostate cancer patients and the mean, standard deviation and 3D-error in AP, RL and SI directions. Setup variations were classified 0-1 mm, 1-3 mm, 3-5 mm, 5 mm and more. Results: The mean and standard deviation of setup variation in AP, RL and SI directions was $1.87{\pm}1.36mm$, $1.73{\pm}1.22mm$ and $2.01{\pm}1.40mm$. The 3D-error in AP, RL and SI directions was $3.63{\pm}1.63mm$. The frequency of setup variation in AP direction was 29 % in the range from 0 mm to 1 mm, 50.2 % in the range from 1 mm to 3 mm, 19.6 % in the range from 3 mm to 5 mm and 1.3 % in the range of 5 mm or more. In RL direction, the frequency was 31.3 % in the range from 0 mm to 1 mm, 52.5 % in the range from 1 mm to 3 mm, 15.8 % in the range from 3 mm to 5 mm and 0.5 % in the range of 5 mm or more. SI direction, the frequency of errors in the range from 0 mm to 1 mm was 26.3 %, 50.2 % in the range from 1 mm to 3 mm, 22.4 % in the range from 3 mm to 5 mm, and 1.1 % in the range of 5 mm or more. Conclusion: The setup error was highest in the SI direction of $2.01{\pm}1.40mm$. The frequency in each direction was the highest in more than 50 % in the range from 1 mm to 3 mm. $Clarity^{TM}$ Auto scan is possible to monitoring the motion of the prostate during the treatment and to repositioning the patient. In conclusion real-time image-guided radiotherapy using ultrasonography will be increase the reproducibility of radiation therapy.

Optimal Conditions for the Production of Sphinin , a Sphingomyelinase Inhibitor from Steptomyces sp. F50970

Si Kyu Lim,Wan Park 한국생명과학회 1999 Journal of Life Science Vol.9 No.2

Production and Characterization of Extracellular Phospholipase D from Streptomyces sp. YU100

( Si Kyu Lim ),( Jae Woong Choi ),( Min Ho Chung ),( Eun Tag Lee ),( Yong Ho Khang ),( Sang Dal Kim ),( Doo Hyun Nam ) 한국미생물 · 생명공학회 2002 Journal of microbiology and biotechnology Vol.12 No.2

Using Streptomyces sp. YU100 isolated from Korean soil, the fermentative production of phospholipase D was attempted along with its purification and characterization studies. When different carbon and nitrogen sources were supplemented in the culture medium, glucose and yeast extract were found to be the best. By varying the concentration of nutrients and calcium carbonate, the optimal culture medium was determined as 2.0% glucose, 1.5% yeast extract, 0.5% tryptone, and 0.3% calcium carbonate. During cultivation, the strain secreted most of the phospholipase D in the early stage of growth within 24h. The phospholipase D produced in the culture broth exhibited hydrolytic activity as well as transphosphatidylation activity on lecithin (phosphatidylcholine). In particular, the culture broth showed 8.7units/ml of hydrolytic activity when cultivated at 28℃ for 1.5days. The phospholipase D was purified using 80% ammonium sulfate precipitation and DEAE-Sepharose CL-6B column chromatography, which produced a major band of 57kDa on a 10% SDS-polyacrylamide gel with purity higher than 80%. The enzyme showed an optimal pH of 7 in hydrolytic reaction, and at pH 4 in a transphosphatidylation reaction. The enzyme activity increased until the reaction temperature was elevated to 60℃. The enzyme was relatively stable at high temperatures and neutral pH, but significantly unstable in the alkaline range. Among the detergents tested as emulsifiers of phospholipids, the highest enzyme activity was observed when 1.5% Triton X-100 was employed. However, no inhibitory effect by metal ions was detected. Under optimized reaction conditions, the purified enzyme not only completely decomposed PC to phosphatidic acid within 1h, but also exhibited higher than 80% conversion rate of PC to PS by transphosphatidylation within 4h.

Isolation of Streptomyces sp. YU100 Producing Extracellular Phospholipase D

(Si Kyu Lim),(Jae Woong Choi),(Eun Tag Lee),(Yong Ho Khang),(Sang Dal Kim),(Doo Hyun Nam) 한국미생물생명공학회 2002 Journal of microbiology and biotechnology Vol.12 No.1

N/A N/A

Isolation of Sphinin , an Inhibitor of Sphingomyelinase , from Streptomyces sp. F50970

(Si Kyu Lim),(Wan Park) 경북대학교 유전공학연구소 2000 遺傳工學硏究所報 Vol.14 No.-

Isolation of Sphinin , an Inhibitor of Sphingomyelinase , from Streptomyces sp. F50970

(Si Kyu Lim),(Wan Park) 한국미생물생명공학회 1999 Journal of microbiology and biotechnology Vol.9 No.5

N/A N/A

Production and Characterization of Extracellular Phospholipase D from Streptomyces sp. YU100

LIM, SI KYU,CHOI, JAE WOONG,CHUNG, MIN HO,LEE, EUN TAG,KHANG, YONG HO,KIM, SANG DAL,NAM, DOO HYUN 영남대학교 약품개발연구소 2002 영남대학교 약품개발연구소 연구업적집 Vol.11 No.-

Using Streptomyces sp. YU100 isolated from Korean soil, the fermentative production of phospholipase D was attempted along with its purification and characterization studies. When different carbon and nitrogen sources were supplemented in the culture medium, glucose and yeast extract were found to be the best. By varying the concentration of nutrients and clacium carbonate, the optimal culture medium was determined as 2.0% glucose, 1.5% yeast extract, 0.5% tryptone, and 0.3% calcium carbonate. During cultivation, the strain secreted most of the phospholipase D in the early stage of growth within 24 h. The phospholipase D in the early stage of growth within 24 h. The phospholipase D produced in the culture broth exhibited hydrolytic activity as well as transphosphatidylation activity on lecithin (phosphatidylcholine). In particular, the culture broth showed 8.7 units/ml of hydrolytic activity when cultivated at 28℃ for 1.5 days. The phospholipase D was purified using 80% ammonium sulfate percipitation and DEAE-Sepharose CL-6B column chromatography,which produced a major band of 57kDa on a 10% SDS-polyacrylamide gel with purity higher than 80%. The enzyme showed an optimal pH of 7 in hydrolytic reaction, and at pH 4 in a transphosphatidylation reaction. The enzyme activity increased until the reacton temperature was elevated to 60℃. The enzyme was relatively stable at high temperatures and neutral pH, but significantly unstable in the alkaline range. Among the detergents tested as cmulsifiers of phospholipids, the highest enzyme activity was observed when 1.5% Triton X-100 was employed. However, no inhibitory effect by metal ions was detected. Under optimized reaction conditions, the purified enzyme not only completely decomposed PC to phosphatidic acid within 1 h, but also exhibited higher than 80% conversion rate of PC to PS by transphosphatidylation within 4 h.

Isolation of Streptomyces sp. YU100 Producing Extracellular Phospholipase D

LIM, SI KYU,CHOI, JAE WOONG,LEE, EUN TAG,KHANG, YONG HO,KIM, SANG DAL,NAM, DOO HYUN 영남대학교 약품개발연구소 2002 영남대학교 약품개발연구소 연구업적집 Vol.11 No.-

Soil samples were screened for actinomucete strains capable of producing phospholipase D, and a strain, Streptomyces sp. YU100, showing a high transphosphatidylation activity was isolated. This strain secreted phospholipase D in a culture broth after 12 h of cultivation, and its productivity continued to increases for 36 h of fermentation. In addituon, its transphosphatidylation rate of phosphatidylcholine to phosphatidylseine was almost 68% within 1 h. The morphological and chemotaxonomical characteristics showed that this strain could be classified as a number of the Streptomycetaceae family, particularly due to the spiral form of its spore chain consisting of 60-70 smooth spores (0.75×1.0??m) on an aerial mycelium, FA-2c type of fatty acid profile in the cell wall, and LL-DAP component in the cell wall peptidoglycan. A phylogenctic analysis of the 16S rDNA provided a clue that the strain YU100 was actually a member of the genus Streptomyces, because the determined sequence exhibited a higher homology with Streptomyes sp. ASB27, S. peucetius JCM9920, and S. griseus ATCC10137. A dendrogram based on the 16S rDNA sequences also showed a phylogenetic relationship between the strain YU100 and these strains. However, the strain YU100 has not yet been assigned to a particular species, because of absence of any other classified species with a high matching score.