• Progress in Superconductivity
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• 제13권3호
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• pp.163-168
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• 2012

The effects of Ta substitution on the superconducting and magnetic properties of the $(Ru_{1-x}Ta_x)Sr_2(Gd_{1.4}Ce_{0.6})Cu_2O_z(0{\leq}x{\leq}0.5)$ system have been investigated. The X-ray diffraction measurements indicate that the Ta ion replaces Ru sites up to x = 0.4. It is found that the Ta substitution for Ru significantly reduces the weak-ferromagnetic component of the field-cooled magnetic susceptibility without an appreciable change of room temperature thermopower at lower Ta doping level below x = 0.2. The resistive transition temperature tends to decrease monotonically from 27 K for the x = 0 sample to 16 K (9 K) for the x = 0.4 (x = 0.5) sample. These results suggest that superconductivity of the $(Ru_{1-x}Ta_x)Sr_2(Gd_{1.4}Ce_{0.6})Cu_2O_z$ compound is not significantly affected by the magnetic state of the Ru sublattice. The experimental results are discussed in connection with previous reports on the effects of Nb substitution.

• Progress in Superconductivity
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• 제13권1호
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• pp.12-17
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• 2011

We investigated the effects of Ba and Cu co-substitution on the structural and superconducting properties of ($Ru_{1-y}Cu_y$)($Sr_{1.67-x}Ba_xEu_{0.33}$)($Eu_{1.34}Ce_{0.66}$)$Cu_2O_z$ samples. X-ray diffraction(XRD) reveals that single-phase samples can be obtained in the range from x = 0.1 to 0.2 for ($Ru_{0.5}Cu_{0.5}$)($Sr_{1.67-x}Ba_xEu_{0.33}$)($Eu_{1.34}Ce_{0.66}$)$Cu_2O_z$ and from y = 0.25 to 0.5 for ($Ru_{1-y}Cu_y$)($Sr_{1.47}Ba_{0.2}Eu_{0.33}$)($Eu_{1.34}Ce_{0.66}$)$Cu_2O_z$, respectively. All samples with compositions of ($Ru_{0.5}Cu_{0.5}$)($Sr_{1.67-x}Ba_xEu_{0.33}$) ($Eu_{1.34}Ce_{0.66}$)$Cu_2O_z$ (x = 0 - 0.33) show superconducting transition behavior and the onset transition temperature decreases slightly with increasing x in consistent with the change of hole concentration estimated from room temperature thermoelectric power measurements. The XRD and resistivity measurements for the ($Ru_{1-y}Cu_y$)($Sr_{1.47}Ba_{0.2}Eu_{0.33}$)($Eu_{1.34}Ce_{0.66}$) $Cu_2O_z$ system indicate that the partial substitution of Cu for Ru is necessary to form phase pure samples, but result in a small change in transition temperature in the single-phase region from x = 0.25 to 0.5.

• 상하수도학회지
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• 제31권5호
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• pp.373-381
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• 2017

$RuO_2$ is a common active component of Dimensionally Stable Anodes (DSAs) for chlorine evolution that can be used in wastewater treatment systems. The recent improvement of chlorine evolution using nanostructures of $RuO_2$ electrodes to increase the treatment efficiency and reduce the energy consumption of this process has received much attention. In this study, $RuO_2$ nanorod and nanosheet electrodes were simply fabricated using the sol-gel method with organic surfactants as the templates. The obtained $RuO_2$ nanorod and nanosheet electrodes exhibit enhanced electrocatalytic activities for chlorine evolution possibly due to the active surface areas, especially the outer active surface areas, which are attributed to the increase in mass transfers compared with a conventional nanograin electrode. The electrocatalytic activities for chlorine evolution were increased up to 20 % in the case of the nanorod electrode and 35% in the case of the nanosheet electrode compared with the nanograin electrode. The $RuO_2$ nanorod 80 nm in length and 20-30 nm in width and the $RuO_2$ nanosheet 40-60 nm in length and 40 nm in width are formed on the surface of Ti substrates. These results support that the templated $RuO_2$ nanorod and nanosheet electrodes are promising anode materials for chlorine evolution in future applications.

• 한국전기전자재료학회논문지
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• 제24권3호
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• pp.200-207
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• 2011

Abstract: The effect of lead free glass frit compositions on the properties of thick film conductor and resistor pastes were investigated. Two types lead free frits, HBF-A(without $Bi_2O_3$) and HBF-B(with $Bi_2O_3$) were made from $SiO_2$, $B_2O_3$, $Al_2O_3$, CaO, MgO, $Na_2O$, $K_2O$, ZnO, MnO, $ZrO_2$, $Bi_2O_3$. And Ag based conductor pastes and $RuO_2$ based resistor paste were prepared by mixed with these frits and functional phase(Ag and $RuO_2$), and organic vehicle. The properties of thick film conductor and resistor sintered at $850^{\circ}C$ were studied after printing on $Al_2O_3$ substrate. The morphology of the sintered films surface were SEM and EDS were carried out to analysis the chemical composition on resistor surface and state of Ru atom in frit matrix.

• Transactions on Electrical and Electronic Materials
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• 제6권4호
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• pp.177-185
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• 2005

Fatigue characteristics of lead zirconate titanate (PZT) films deposited by electron cyclotron resonance plasma enhanced chemical vapor deposition (ECR-PECVD) were investigated. The fatigue characteristics were investigated with respect to PZT film thickness, domain structure, fatigue pulse height, temperature, electrode materials and electrode configurations. The used top and bottom electrode materials were Pt and $RuO_2$. In the fatigue characteristics with fatigue pulse height and PZT film thickness, the fatigue rates are independent of the applied fatigue pulse height at the electric field regions to saturate the P-E hysteresis and polarization $(P^*,\;P^A)$ characteristics. The unipolar and bipolar fatigue characteristics of PZT capacitors with four different electrode configurations $(Pt//Pt,\;Pt//RuO_2,\;RuO_2//Pt,\;and\;RuO_2//RuO_2)$ were also investigated. The polarization-shifts during the unipolar fatigue and the temperature dependence of fatigue rate suggest that the migration of charged defects should not be expected in our CVD-PZT films. It seems that the polarization degradations are attributed to the formation of charged defects only at the Pt/PZT interface during the domain switching. The charged defects pin the domain wall at the vicinity of Pt/PZT interface. When the top and bottom electrode configurations are of asymmetric $(Pt//RuO_2,\;RuO_2//Pt)$, the internal fields can be generated by the difference of charged defect densities between top and bottom interfaces.

• 전자공학회논문지D
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• 제34D권8호
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• pp.8-14
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• 1997

RuO$_{2}$ thin films are prepared by RF magnetron reactive sputtering and their characteristics of crystallization, microstructue, surface roughness and resistivity are studied with various O$_{2}$/(Ar+O$_{2}$) ratios and substrate temperatures. As O$_{2}$/(Ar+O$_{2}$) ratio decreas and substrate temperature increases, the preferred growing plane of RuO$_{2}$ thin films are changed from (110) to (101) plane. With increase of the O$_{2}$/(Ar+O$_{2}$) ratio from 20% to 50%, the surface roughness and the resistivity of RuO$_{2}$ thin films increase form 2.38nm to 7.81 nm, and from 103.6.mu..ohm.-cm to 227.mu..ohm.-cm, resepctively, but the deposition rate decreases from 47 nm/min to 17nm/min. On the other hand, as the substrate temperature increases form room temperature to 500.deg. C, resistivity decreases from 210.5.mu..ohm.-cm to 93.7.mu..ohm.-cm. RuO$_{2}$ thin film deposited at 300.deg. C shows a execellent surface roughness of 2.38nm. As the annealing temperature increases in the range between 400.deg. C and 650.deg. C, the resistivity decreases because of th improvement of crystallinity. We find that RuO$_{2}$ thin film deposited at 20% of O$_{2}$/(Ar+O$_{2}$) ratio and 300.deg. C of substrate temperature shows execellent combination of surface smoothness and low resistrivity so that it is well qualified for bottom electrodes for ferroelectric thin films.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2000년도 추계종합학술대회
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• pp.494-498
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• 2000

RuO$_2$ thin films are prepared by RF magnetron reactive sputtering and their characteristics of crystallization, microstructure, surface roughness and resistivity are studied with various $O_2$/ (Ar+O$_2$) ratios and substrate temperatures. As $O_2$/(Ar+O$_2$) ratio decreases and substrate temperature increases, the preferred growing plane of RuO$_2$ thin films are changed from (110) to (101) plane. With increase of the $O_2$/(Ar+O$_2$) ratio from 20% to 50%, the surface roughness and the resistivity of RuO$_2$ thin films increase from 2.38nm to 7.81 nm, and from 103.6 $\mu$$\Omega$-cm to 227 $\mu$$\Omega$-cm, respectively, but the deposition rate decreases from 47 nm/min to 17 nm/min. On the other hand, as the substrate temperature increases from room temperature to 500 $^{\circ}C$, resistivity decreases from 210.5 $\mu$$\Omega$-cm to 93.7 $\mu$$\Omega$-cm. RuO$_2$ thin film deposited at 300 $^{\circ}C$ shows a excellent surface roughness of 2.38 nm. As the annealing temperature increases in the range between 400 $^{\circ}C$ and 650 $^{\circ}C$, the resistivity decreases because of the improvement of crystallinity. We find that RuO$_2$ thin film deposited at 20% of $O_2$/(Ar+O$_2$) ratio and 300 t of substrate temperature shows excellent combination of surface smoothness and low resistivity so that it is well Qualified for bottom electrodes for ferroelectric thin films.

• 대한환경공학회지
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• 제34권11호
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• pp.715-719
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• 2012

단위면적당($cm^2$) 루테늄의 코팅량이 1.5 mg, 2.5 mg, 3.5 mg, 5.5 mg, 8.5 mg의 $RuO_2$/Ti 전극을 제조하여 코팅량에 따른 전기화학적 특성 차이와 염소 발생에 미치는 영향을 조사하였다. 순환전압 실험 결과 루테늄이 코팅된 전극의 염소 발생 과전압은 약 1.15 V (vs. Ag/AgCl)로 거의 일정하였다. 그러나 교류 임피던스 분광법, 동전위분극실험 결과 단위면적당($cm^2$) 루테늄의 코팅량이 2.5 mg, 3.5 mg $RuO_2$/Ti 전극의 저항은 각각 $0.4582{\Omega}$, $0.5267{\Omega}$, 부식속도는 각각 0.082 mm/yr, 0.058 mm/yr로 내구성이 가장 우수하였다. 염소 발생량은 단위면적당($cm^2$) 루테늄의 코팅량 3.5 mg 전극이 15.2 mg/L로 가장 높게 측정되었다.

• 공업화학
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• 제31권2호
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• pp.200-207
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• 2020

본 연구에서는, NH₃-SCO (selective catalytic oxidation) 반응에서 RuTi 촉매 제조 시 소성온도에 따른 영향을 확인하였다. RuTi 촉매는 습윤 함침법을 이용하여 제조되었고, 공기 분위기에서 400~600 ℃로 4 h 동안 소성되었다. 촉매는 RuTi x00로 표기되었으며, x00는 소성온도를 의미한다. XRD, TEM, H₂-TPR 분석에 따르면, RuTi x00 촉매는 소성온도가 증가할수록 활성금속의 분산도가 감소하는 것을 나타내었다. XPS, NH₃-TPD 분석을 통하여, 낮은 분산도를 갖는 촉매는 표면 흡착 산소 종(O_β) 및 NH₃ 흡착량이 감소하는 특성을 나타내었다. 따라서 RuTi 400 촉매는 TiO₂ 표면에 활성금속이 가장 잘 분산되었으며, NH₃ 제거 효율이 가장 우수하였다.

• 전자공학회논문지A
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• 제29A권11호
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• pp.84-90
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• 1992

The dependence of electrical characteristics of RuO$_2$-based thick film resistors on the RuO$_2$ contents, glass composition variation and the firing temperatures was measured. The sheet resistance of resistors decreased as the contents of RuO$_2$ increased and at firing temperatures higher than C, the sheet resistance increased as the firing temperature increased. In case of using lead borosilicate glass-containing $Bi_{2}O_{3}$, the sheet resistance decreased as the contents of $Bi_{2}O_{3}$ increased. TCR changes from negative to positive values as RuO$_2$ contents increased and from positive to negative values as the firing temperature increased. TCR increased to positive values as $Bi_{2}O_{3}$ increased in the glass.