1,967 research outputs found
A study on the improvement of fracture toughness of adhesive joints at cryogenic temperatures
No full text학위논문(석사) - 한국과학기술원 : 기계공학전공, 2009.2, [ iii, 80 p. ]한국과학기술원 : 기계공학전공
Wear behavior of Al-Fe-Cr-Ti alloys fabricated by Magnetic Pulsed Compaction
No full textRumman Md. Raihanuzzaman, Joon Ho Kim, Jin Kyu Lee, Jae Sik Yoon, Hyeon-Taek Son, Soon-Jik Hon
The fabrication of the thin films by chemical vapour deposition and the effect of the deposition parameters on the physical, electical, and optical properties of deposited films
No full text학위논문(박사) - 한국과학기술원 : 재료공학과, 1988.8, [ vi, 123 p. ]IV-3. 화학증착법을 이용하여 강유전체 재료인 Lead Titanate 박막을 제조하였다. IV-3-1. Substrate reaction Pbo와 모재인 티타늄과의 반응에서 Lead Titanate를 제조하여 다음 결과를 얻었다. 1. 증착층은 주상정 조직을 가지며 모재에 수직으로 성장한다. 2. 박막과 모재사이에 titanium dioxide의 interlayer가 형성되었다. 3. 의 유전상수와 유전손실은 박막두께에 관계없이 일정하며 양호한 성질을 나타낸다. VI-3. 의 혼합 기체를 이용한 Lead Titanate의 화학 화학증착에서 증착층의 화학 조성을 AES 와 XPS 를 사용하여 얻어서 다음과 결론을 얻었다. (1)표준 시편을 사용하여 증착층의 조성을 AES 와 XPS로 분석하였다.\\ Table.14 Comparison XPS and AES results for a sputter cleaned \varphi=45\,^\circ to the normal to the sample. \begin{center} \begin{tabular}{rrrr}\hline & \underline{Pb(at.\%)} & \underline{Ti(at.\%)} & \underline{O(at.\%)}\cos \varphi = 0.87) & 20.4 & 19.5 & 60.1\\ XPS(\varphi\qquad = 45\,\^circ) & 16.94 & 26.84 & 56.2 \\ \hline \end{tabular} \end{center} Deposition condition: deposition temperature, 750\,^\circ\!C;\; Ti(C_2H_5O)_4O_2PbTiO_3 films for various deposition temperatures (by XPS)\\ \begin{center} \begin{tabular}{|r|rrrr} \hline & \multicolumn{4}{|c|} Various deposition temperature (^\circ\!C)\\ \hline & \underline{600} & \underline{650} & \underline{700} & \underline{750}\\ Pb(a.c) & 0.183 & 0.171 & 0.179 & 0.167\\ Ti(a.c) & 0.261 & 0.263 & 0.270 & 0.269 & O(a.c) & 0.556 & 0.566 & 0.551 &0.564\\ \hline \end{tabular} \end{center} Table.16 Atomic compositions of the films for various fractions(by XPS)\\ \begin{center} \begin{tabular}{|r|rrr} \hline & \multicolumn{3}{|c|} Various fractions\\ \hline & & & \\ Pb(a.c) & 0.115 & 0.103 & 0.112 \\ Ti(a.c) & 0.219 & 0.208 & 0.237 \\ O(a.c) & 0.667 & 0.689 & 0.651\\ \hline \end{tabular} \end{center} (2) 반응기체유량 800sccm, 분율0.15, $한국과학기술원 : 재료공학과
Improvement of the adhesive peel strength of the secondary barrier with level difference for LNG containment system
No full textCryogenic containment systems for LNG (Liquefied Natural Gas) ships are required to satisfy durability and safety for 40 years of operation. Membrane type LNG containment ships generally consist of three parts such as the primary barrier which is made of stainless steel, the secondary barrier which is made of composite or metal foil, and the insulation board which is made of polymer foam. The secondary barriers which are the face parts of insulation boards are adhesively bonded with metal strips to keep the gas tightness. When LNG is loaded in the containment system, large thermal stresses are generated in the metal strips due to the cryogenic temperature of LNG (-163oC). If there is a level difference between the insulation boards, the adhesively bonded metal strips are subjected to peel stress due to the level difference.
In this research, FEM analysis was performed to calculate the critical peel stress with the level difference of 3 mm between the insulation boards due to the non-uniform flatness of the inner hull structure of LNG ships. To verify the adhesive strength, a new peel test method representing height differences of the secondary barrier was developed. Finally, the adhesive was reinforced with glass fiber to increase the peel strength of adhesive and the optimal volume fraction of glass fiber reinforcement was determined by the new peel test method
Supplemental_Figure – Supplemental material for Repeated low-dose rituximab treatment based on the assessment of circulating B cells in patients with refractory myasthenia gravis
No full textSupplemental material, Supplemental_Figure for Repeated low-dose rituximab treatment based on the assessment of circulating B cells in patients with refractory myasthenia gravis by Kyomin Choi, Yoon-Ho Hong, So-Hyun Ahn, Seol-Hee Baek, Jun-Soon Kim, Je-Young Shin and Jung-Joon Sung in Therapeutic Advances in Neurological Disorders</p
SBT강유전체 박막 형성 방법
No full textA method for forming SBT ferroelectric thin film. Sr(C.sub.5 F.sub.6 HO.sub.2).sub.2, Bi(C.sub.6 H.sub.5).sub.3 and Ta(C.sub.2 H.sub.5 O).sub.5 are used as the precursors of Sr, Bi and Ta and bubbled at a temperature of 110-130.degree. C., 140-160.degree. C., and 120-140.degree. C., respectively. The deposition of the precursors on a substrate is carried out at 500-550.degree. C. in plasma by using an RF power of 100-150 W. Having a residual polarity (Pr) of 15 .mu.C/cm.sup.2 or higher and a coercive electric field (Ec) of 50 kV/cm or less and, the SBT ferroelectric thin film does not show a fatigue phenomenon until 1.times.10.sup.11 cycles as measured under 6V bipolar square pulse in the structure comprising Pt upper and lower electrodes and thus, can be applied for non-volatile memory devices
Influence of narrow transverse slit in ferroelectric based voltage tunable phase shifter
No full textWe report on gold/Ba0.5Sr0.5TiO3 (BST) ferroelectric thin film Ku-band phase shifters designed and fabricated on MgO substrates using two different structures; the coplanar waveguide (CPW) meander line phase shifter and the new phase shifter with narrow transverse slits in the ground plane of the CPW structure. The ability of these devices to provide a variable phase shift is based on the change in dielectric constant of BST with an applied dc bias. The phase shifter with narrow transverse slits showed larger phase shift capability than that of the conventional meander line phase shifter. In I the former phase shifter, the phase shift of about 10.6 as a maximum value for the frequency range from 16 GHz to 18 GHz Was obtained. In the latter, the phase shift of 9.7 deg at 18 GHz and at an applied voltage of 30 V was measured
Biomimetic Artificial Nacre: Boron Nitride Nanosheets/Gelatin Nanocomposites for Biomedical Applications
No full textA bioinspired boron nitride nanosheet (BNNS)/gelatin nanocomposite consisting of hierarchically aligned layered BNNSs bonded with gelatin is fabricated by using electrostatic interactions between the oppositely charged functional groups on gelatin and the BNNSs. To enhance the self‐assembly and interfacial bond strength between these entities, the BNNSs are functionalized using hyperbranched polyglycerol. The 2D alignment of the BNNSs can be controlled by increasing the amount of BNNSs, or by a functionalization process, both of which result in transformation of the nanoscale structure from a randomly oriented to a brick‐and‐mortar structure. The mechanical properties of the resulting nanocomposite material, including the strength and modulus, are controlled by changing the composition of BNNSs and gelatin in the nanocomposite and by modifying the degree of alignment of the BNNSs in the material. This tuning of the mechanical properties yields a material whose performance resembles that of human cortical bone. In vitro cell viability experiments on the BNNSs/gelatin nanocomposite reveal that this artificial nacre supports adhesion, viability, and proliferation of adipose‐derived stem cells, all of which are essential for biomedical applications. Mechanical and biological testing of the material suggests applications of artificial nacre in biomedical fields and for tissue regeneration.
JHC761652_Supplemental_Material – Association Between Fibroblast Growth Factor Receptor 1 Gene Amplification and Human Papillomavirus Prevalence in Tonsillar Squamous Cell Carcinoma With Clinicopathologic Analysis
No full textSupplemental material, JHC761652_Supplemental_Material for Association Between Fibroblast Growth Factor Receptor 1 Gene Amplification and Human Papillomavirus Prevalence in Tonsillar Squamous Cell Carcinoma With Clinicopathologic Analysis by Soonchan Park, Miji Lee, Kyung-Ja Cho, Sung Bae Kim, Jong-Lyel Roh, Seung-Ho Choi, Soon Yuhl Nam, Sang Yoon Kim and Joon Seon Song in Journal of Histochemistry & Cytochemistry</p
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