• Title/Summary/Keyword: surface treatment material

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Shear bond strength of indirect composite material to monolithic zirconia

  • Sari, Fatih;Secilmis, Asli;Simsek, Irfan;Ozsevik, Semih
    • The Journal of Advanced Prosthodontics
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    • v.8 no.4
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    • pp.267-274
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    • 2016
  • PURPOSE. This study aimed to evaluate the effect of surface treatments on bond strength of indirect composite material (Tescera Indirect Composite System) to monolithic zirconia (inCoris TZI). MATERIALS AND METHODS. Partially stabilized monolithic zirconia blocks were cut into with 2.0 mm thickness. Sintered zirconia specimens were divided into different surface treatment groups: no treatment (control), sandblasting, glaze layer & hydrofluoric acid application, and sandblasting + glaze layer & hydrofluoric acid application. The indirect composite material was applied to the surface of the monolithic zirconia specimens. Shear bond strength value of each specimen was evaluated after thermocycling. The fractured surface of each specimen was examined with a stereomicroscope and a scanning electron microscope to assess the failure types. The data were analyzed using one-way analysis of variance (ANOVA) and Tukey LSD tests (${\alpha}$=.05). RESULTS. Bond strength was significantly lower in untreated specimens than in sandblasted specimens (P<.05). No difference between the glaze layer and hydrofluoric acid application treated groups were observed. However, bond strength for these groups were significantly higher as compared with the other two groups (P<.05). CONCLUSION. Combined use of glaze layer & hydrofluoric acid application and silanization are reliable for strong and durable bonding between indirect composite material and monolithic zirconia.

The morphology and Phtoelectrochemical properties of $TiO_2$ electrode with UV Treatment and Oxygen Injection (산소와 UV 조사된 $TiO_2$ 광전극의 표면형상과 전기화학적 특성)

  • Zhao, Xingguan;Jin, En Mei;Park, Kyung-Hee;Gu, Hal-Bon;Park, Bok-Kee
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2010.06a
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    • pp.240-240
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    • 2010
  • In this paper, in these case of photoelectrode using UV treatment after oxygen solar conversion efficiency is increased. According to oxygen injection UV treatment will removal residual organics and increase the TiO2 surface area but also UV treatment can affect the same chemical action of ozone treatment. More porous networks and larger porosities were obtained in the TiO2 films prepared UV treatment after oxygen injection.

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A STUDY ON THE SHEAR BOND STRENGTH OF COMPOMER ACCORDING TO SURFACE TREATMENT (Compomer의 치면처리방법에 따른 전단 결합 강도에 관한 연구)

  • Kim, Jin-Yong;Hong, Chan-Ui
    • Restorative Dentistry and Endodontics
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    • v.23 no.1
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    • pp.247-256
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    • 1998
  • To evalutate the change in shear bond strength according to dentin surface treatment, 4 materials were divided into control group(A) and experimental group(B). Group A was treated according to the instruction of manufacture. Group B was treated with 32% phosphoric acid. After dentin surface treatment, each material was bonded and stored in 100% humidity during 7 days, and then, the shear bond strength was evaluated. The results were as follows: 1. In the case of treatment according to the instruction of manufacture, the shear bond strength according to material showed Z-100 to be highest with 12.42 MPa, Compoglass had the lowest shear bond strength with 4.23 MPa and there was significant difference between Compoglass and Z-100, Dyract (p<0.01). 2. The group treated with 32% phosphoric acid showed lower shear bond strength than that of the group treated according to the instruction of manufacture but there was no statistical significance. 3. As a result of observation under SEM, the fracture pattern was a mixture of cohesive and adhesive failure in group 1, and there was more adhesive failure in group 2, and in group 3 and 4 there was cohesive failure of material or tooth structure. From the results above Dyract showed shear bond strength levels between resin and resin -modified glass ionomer but Compoglass showed much lower shear bond strength than that of resin-modified glass ionomer thus indicating that even though they are the same type of material they show evident differences in physical properties. And it is thought that the treatment of dentin surface with phosphoric acid did not increase the shear bond strength, unlike enamel.

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MoS2/CNFs derived from Electrospinning and Heat treatment as the Efficient Electrocatalyst for Hydrogen Eovlution Reaction in Acidic Solution (전기 방사를 이용한 1D / 2D 하이브리드 구조 고활성 MoS2 / CNF 수소 발생 촉매의 합성 및 특성 분석)

  • Lee, Jeong Hun;Park, Yoo Sei;Jang, Myeong Je;Park, Sung Min;Lee, Kyu Hwan;Choi, Woo Sung;Choi, Sung Mook;Kim, Yang Do
    • Korean Journal of Metals and Materials
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    • v.56 no.12
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    • pp.885-892
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    • 2018
  • Molybdenum disulfide ($MoS_2$) based electrocatalysts have been proposed as substitutes for platinum group metal (PGM) based electrocatalyst to hydrogen evolution reaction (HER) in water electrolysis. Here, we studied $MoS_2/CNFs$ hybrid catalyst prepared by electrospinning method with heat treatment for polymer electrolyte membrane(PEM) water electrolysis to improve the HER activity. The physicochemical and electrochemical properties such as average diameter, crystalline properties, electrocatalitic activity for HER of synthesized $MoS_2/CNFs$ were investigated by the Scanning Electron Microscope (SEM), X-ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), Transmission Electron Microscopy (TEM), Raman Spectroscopy (Raman) and Linear Sweep Voltammetry (LSV). The as spun ATTM/PVP nanofibers were prepared by sol-gel and electrospinning method. Subsequently, the $MoS_2/CNFs$ was dereived from reduction heat treatment of ATTM at the ATTM/PVP nanofibers and carbonization heat treatment. Synthesized $MoS_2/CNFs$ electrocatalyst had an average diameter of $179{\pm}30nm$. We confirmed that the $MoS_2$ layers in $MoS_2/CNF$ electrocatalyst consist of 3~4 layers from the Raman results. In addition, We confirmed that the $MoS_2$ layers in $MoS_2/CNF$ catalyst consist of 7.47% octahedral 1T phase $MoS_2$, 63.77% trigonal prismatic 2H phase $MoS_2$ with 28.75% $MoO_3$ through the XRD, Raman and XPS results. It was shown that $MoS_2/CNFs$ had the overpotential of 0.278 V at $10mA/cm^2$ and tafel slope of 74.8 mV/dec in 0.5 M sulfuric acid ($H_2SO_4$) electrolyte.

Electrical Properties of Yellow Emitting OLED (Yellow 발광 OLED의 전기적 특성)

  • Hong, Kyung-Jin;Ki, Hyun-Chol;Min, Yong-Ki
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.06a
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    • pp.325-326
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    • 2009
  • We studied the effect of ITO surface treatment by using $O_2$ plasma to enhance the emission efficiency of the Organic Light Emitting Diodes (OLEDs). The luminance efficiency and the operational stability were improved with an ITO anode treated at the optimized conditions.

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Development Trend of Ni-less Surface Treatment Technology for Semiconductor Packaging Substrates (반도체 패키지 기판용 Ni-less 표면처리 기술 개발동향)

  • Min-Kyo Cho;Jin-Ki Cho;Kyoung-Min Kim;Sung Yong Kim;Deok-Gon Han;Tae-Hyun Sung
    • Journal of the Microelectronics and Packaging Society
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    • v.30 no.1
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    • pp.49-54
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    • 2023
  • Recently, System in Packaging(SIP) technology needs to meet high frequency (5G and more) communication technology and fine pitch surface treatment. The conventional Electroless Ni/Immersion Au plating(ENIG) is not suitable for high frequency range because of magnetic properties are increasing the transmission loss. Without nickel plating layer, the pattern and pad reliability level must be meet the condition. In this review paper, we investigated research trends on Ni-less surface treatment technology for high-frequency communication and frequency characteristics according to materials.

Structural Characteristics Analysis of Stone Contact Surface according to Surface Roughness and Filling Material of Stone Pagoda Structure (석탑구조물의 표면거칠기 및 충전재에 따른 석재접촉면의 구조특성 분석)

  • Kim, Ho-Soo;Kim, Dong-Kwan;Lee, Seung-Hee;Kim, Derk-Moon;Jo, Sang-Sun
    • Journal of the Architectural Institute of Korea Structure & Construction
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    • v.34 no.6
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    • pp.19-27
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    • 2018
  • The stone pagoda structure is treated as a discontinuous masonry structure, and the contact surface characteristics between stones is a very important factor in the discontinuum behavior analysis. So, it is necessary to find out material and structural characteristics of stone contact surface to perform the structural analysis for safety evaluation. Accordingly, it is important to analyze the material properties of stone surface and secure the structural characteristics through various contact surface states. Therefore, in this study, various test specimens applying the filler between the surface roughness and the stone in the contact surface treatment technique of the stone pagoda were manufactured, and compression test and shear test were carried out. Also, we analyzed the material and structural characteristics of the stone contact surface through the comparison of experimental results.

Anodic Performances of Surface-Treated Natural Graphite for Lithium Ion Capacitors

  • Park, Chul Min;Jo, Yong Nam;Park, Jung Woo;Yu, Ji-Sang;Kim, Jeom-Soo;Choi, Jungkyu;Kim, Young-Jun
    • Bulletin of the Korean Chemical Society
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    • v.35 no.9
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    • pp.2630-2634
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    • 2014
  • The surface of natural graphite was modified by the use of hydrogen peroxide and evaluated as an anode material for lithium ion capacitors (LICs). The surface treatment was carried out under various ultrasonic conditions of 200, 300, and 400W, which were applied to a mixture of natural graphite and hydrogen peroxide solution for 1 h. While the bulk structure was maintained, the hexagonal symmetry and physical properties of natural graphite, such as BET surface area, tap density, and particle size, were affected by the surface treatment. FT-IR and XPS measurements confirmed the signature of C=O on the surface of graphite samples after treatment. Both the pristine and surface-treated graphites showed a similar reversible capacity of $370mAhg^{-1}$, and the coulombic efficiency of surface-treated graphite decreased with higher ultrasonic energies (89.1%, 89.0%, and 88.0% for 200, 300, and 400 W) comparing with pristine graphite (89.4%). The capacity retention of LICs was greatly improved with the treated natural graphite. The graphite treated under the ultrasonic energy of 300 W and pristine natural graphite showed capacity retention of 77.5% and 42.9%, implying that the surface treatment was an effective method for the improvement of natural graphite as an anode material for LICs.

Surface Properties and Adhesion of Semiconducting and Insulating Silicone Rubber by Corona Discharge Treatment (코로나 방전처리에 의한 반도전-절연 실리콘 고무의 표면특성 및 접착특성)

  • Lee, Ki-Taek;Hwang, Sun-Mook;Hong, Joo-Il;Huh, Chang-Su
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.19 no.9
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    • pp.868-872
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    • 2006
  • In this work, the effects of the corona treatment on surface properties of semiconducting silicone rubber were investigated in terms of contact angles, ATR-FTIR(Attenuated total reflection fourier transform infrared spectroscopy) and XPS(X-ray photoelectron spectroscopy). And the adhesive characteristics were studied by measuring the T-peel strengths. Based on chemical analysis, the surface modification can be mainly ascribed to the creation of chemically active functional groups such as C-O, C=O and C-OH on semiconducting silicone surface. This oxidized rubber layer is inorganic silica-like structure of Si bound with three to four oxygen atoms ($SiOx,\;x=3{\sim}4$. The Corona treatment produces an increase in joint strength that is maximum for 10 min treatment. However, due to brittle property of this oxidized layer, the highly oxidized layer from too much extended treatment could be act as a weak point, decreasing the adhesion strength.

Optical Properties of Organic Light Emitting Diode and Characteristics of ITO by Variation of Radio Frequency Plasma Power (Radio Frequency Plasma Power변화에 따른 ITO 특성 및 OLED의 광학적 특성)

  • Ki, Hyun-Chul;Kim, Hwe-Jong;Hong, Kyung-Jin;Kim, En-Mei;Gu, Hal-Bon
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.22 no.1
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    • pp.81-85
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    • 2009
  • We has been analysed optical properties of OLED(organic light emitting diode) and characteristics of ITO(Indium Tin Oxide) in terms of $O_2$ plasma treatment for manufacturing high efficiency OLED, RF power of $O_2$ plasma was changed 25, 50, 100, 200 W. $O_2$ gas flow, gas pressure and treatment time were fixed. Sheet resistance and surface roughness of ITO were measured by Hall-effect measurement system and AFM, respectively. The ranges of sheet resistance and surface roughness were $5.5{\sim}6,06\;{\Omega}$ and $2.438{\sim}3.506\;nm$ changing of RF power, respectively, PM(Passive Matrix)OLED was fabricated with the structure of ITO(plasm treatment)/TPD($400\;{\AA}$)/$Alq_3(600\;{\AA})$/LiF($5\;{\AA}$)/Al($1200\;{\AA}$). Turn-on voltage of PMOLED was 7 V and luminance was $7,371\;cd/m^2$ at the RF power of 25 W, $O_2$ plasma treatment of ITO surface was result in lowering the operating voltage and improving luminance of PMOLED.