• Proceedings of the Optical Society of Korea Conference
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• 1998.08a
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• pp.78-79
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• 1998

• Journal of the Korean Chemical Society
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• v.58 no.5
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• pp.437-444
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• 2014

The electrochemical corrosion and passivation of Co-RDE in borate buffer solution was studied by Potentiodynamic and electrochemical impedance spectroscopy. The mechanisms of both the active dissolution and passivation of cobalt and the hydrogen evolution in reduction reaction were hypothetically established while utilizing the Tafel slope, the rotation speed of Co-RDE, impedance data and the pH dependence of corrosion potential. Based on the EIS data, an equivalent circuit was suggested. In addition, the electrochemical parameters for specific anodic dissolution regions were carefully measured. An induction loop in Nyquist plot measured at the open-circuit potential was observed in the low frequency, and this could be attributed to the adsorption-desorption behavior in the corrosion process.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.4 no.3
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• pp.218-222
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• 2003

본 연구의 목표는 난연화를 위한 기존 공법의 단점 보완과 환경 친화적인 난연제를 사용한 비 난연 XLPE 케이블의 난연화 방법과 최적의 난연 코팅액 배합에 있다. 전력용, 통신용 둥과 같이 고난연성이 요구되는 경우 기존 컴파운드 방법으로는 난연제를 다량으로 첨가하여 사용하며, base polymer와의 혼합성, 기계적인 물성에도 영향을 끼쳐서는 안 되는 등 여러 가지 요구 조건을 만족시켜야 하는 문제점을 가지고 있다. 각 난연 코팅액에 따른 코팅 표면을 고찰한 결과 모든 코팅의 표면은 깨끗하였으며, 코팅층의 두께는 약 10-20㎛로 일정하게 코팅이 되었다. TBBA/Sb₂O₃, TBBA/Zinc Borate의 무게비(wt%)가 1:0.7 이상부터 난연 효과를 보였다. 또한 Mg(OH)₂/Zinc Borate의 경우는 무게비(wt％)가 1:0.5, 1:0.6에서 난연효과를 보였으나, 1:0.7 이상에서는 난연 효과가 떨어지는 현상을 보였다. Mg(OH)₂/AF100 S/Zinc Borate의 경우는 AF100 S의 첨가량이 증가할수록 난연성이 향상되었다. 난연 코팅액의 열 분해 거동을 비교한 결과, Mg(OH)₂/Zinc Borate의 경우 초기 분해 온도가 유기계 난연제를 사용하였을 경우보다 늦어졌으며, 최종 잔류 탄화물 양도 많이 생성되었다. Mg(OH)₂/AF100 S/Zinc Borate의 경우 난연 효과를 상승을 위해 인계 난연제(AF100 S)를 첨가하였으나. 오히려 초기 분해온도가 빨라졌으며 잔류 탄화물의 양도 적게 나타났다. 그러나 연소 테스트 결과 가장 우수한 난연 효과를 보였다.

• Journal of the Korean Ceramic Society
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• v.50 no.5
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• pp.341-347
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• 2013

Kaolin-based membranes with a pore size of 0.30-0.40 ${\mu}m$ were successfully prepared by a simple pressing route using low-cost starting materials, kaolin and sodium borate. The prepared green bodies were sintered at different temperatures ranging between 900 and $1200^{\circ}C$. The sintered membranes were characterized by X-ray diffraction, mercury porosimetry, scanning electron microscopy, and capillary flowmetry. It was observed that the porosity decreased with an increase in both the sintering temperature and the sodium borate content, whereas the flexural strength increased with an increase in both the sintering temperature and the sodium borate content. The air flow rate decreased with an increase in the sodium borate content. The typical porosity, flexural strength, and specific flow rate of the kaolin-based membrane sintered with 5 wt% sodium borate at $1100^{\circ}C$ were 37%, 19 MPa, and $1{\times}10^{-3}L/min/cm^2$, respectively, at a p of 30 psi.

• Journal of the Korean Electrochemical Society
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• v.10 no.1
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• pp.14-19
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• 2007

The corrosion and passivation of copper was investigated with the copper rotating disk electrode(Cu-RDE) in borate buffer solution. It has been observed with the mixed potential theory that the corrosion potential for the rotation rate increase under the convective diffusion condition was increased. It was suggested that the chemical intermediates and product 13. the copper oxidation were $Cu(OH)_{ads},\;{Cu(OH)_2}^-,\;Cu_2O,\;Cu(OH)_2,\;and\;CuO$.

• Transactions on Electrical and Electronic Materials
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• v.7 no.6
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• pp.309-312
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• 2006

This study shows to blend ethylene vinyl acetate(EVA) and a flame retardant agent, $Mg(OH)_{2}$, and synergists, zinc borate for improving flame retardancy of low density polyethylene(LDPE). And it studied the property of flame retardancy of LDPE/EVA blend by the amount of addition through LOI and TGA, estimated the electrical characteristics such as volume resistivity and breakdown strength. The flame retardancy of LDPE/EVA blend was much improved in case of adding zinc borate with 6phr degree, and the electrical characteristics were more or less decreased depending on increasing the amount of addition. Zinc borate used for improving the flame retardancy of LDPE/EVA blend let the added amount of a flame retardant agent, $Mg(OH)_{2}$ limited, and the electrical characteristics decreased extremely by adding a good deal of $Mg(OH)_{2}$.

• Macromolecular Research
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• v.16 no.2
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• pp.134-138
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• 2008

A novel acrylol borate was designed and synthesized by reacting acrylate monomer and boric acid. The obtained acrylol borate was used as both gelator and anion receptor for the liquid electrolyte in a lithium secondary battery. It was found that the ionic conductivity of the gel polymer electrolyte (GPE) was as high as that of the liquid electrolyte, and the thermal stability of GPE was increased when only 2 wt% acrylol borate was incorporated into the liquid electrolyte. These results suggest that acrylol borate can be used as an effective additive to enhance the thermal stability of the electrolyte without adversely affecting its conductivity. It is believed that the strong complex formation between boron in the gelator and the anion of the salt is responsible for the enhanced thermal stability of the electrolyte solution and the increased ionic conductivity.

• Nuclear Engineering and Technology
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• v.55 no.6
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• pp.2166-2171
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• 2023

In the present study, six silicone rubber doped by tellurium borate oxides were fabricated using the casting method. The densities of the fabricated silicon rubber-doped by tellurium borate oxides samples were measured using the Archimedes Method. Moreover, the linear attenuation coefficient of silicone rubber doped tellurium borate oxides samples was evaluated experimentally using the hyper pure germanium, and the recorded linear attenuation coefficient values were affirmed using the theoretical Phy-X program. The experimental measurements were performed using the narrow beam transmission method with radioactive isotopes Am-241, Cs-137, and Co-60 with energies of 59, 661, 1173, and 1332 keV. The linear attenuation coefficient values showed an enhancement by 4.73 times, 1.20 time, 1.17, time, and 1.17 time, respectively at gamma photon energies of 59, 661, 1173, and 1332 keV, when the TeO₂ concentration increased in the fabricated composites from 0 to 50 wt%. The enhancement of the linear attenuation coefficient values has a positive effect on the transmission rate values where the half-value thickness and transmission rate were decreased accompanied by an increase in the RPE.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.585-587
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• 2008

Depending on host environments, $Eu^{2+}$ emission can be spectrally tuned by manipulating the energy levels between allowed $4f{\leftrightarrow}5d$ transition. Spectral variations of $Eu^{2+}$ emission from narrow green emission to broad yellow emission band were achieved by varying the host lattices such as Sr- or Ba-silicate, borate, and borosilicate.

• KSTLE International Journal
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• v.2 no.2
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• pp.138-141
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• 2001

Tribological behaviors of a borate of triethanolamine in water solution were evaluated using a four-ball wear tester. X-ray photoelectron spectroscopy (XPS) was employed to study tribochemical species on worn scars of steel balls. Results show that a thick deposit layer was produced on the worn scars, which came from the decomposition of the borate. The surface film on the worn scars was mostly consisted with H$_3$BO$_3$, B$_2$O$_3$and large amounts of ferricyanides.