• Journal of the Korean Chemical Society
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• v.55 no.4
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• pp.575-580
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• 2011

It was investigated into the effects on zinc corrosion of the rotation speed of Zn-RDE and the oxygen concentration in borate buffer solution. Zinc corrosion was heavily influenced on the rotation speed of electrode and the oxygen concentration. We have suggested the disproportion reaction following the reversible one electron transfer as the corrosion mechanism of zinc.

• Journal of the Korean Wood Science and Technology
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• v.35 no.5
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• pp.46-57
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• 2007

The leachability of boron in zinc borate (ZB)-modified oriented strandboard (OSB) from southern wood species was investigated in this study. The leaching experiments were conducted by exposing edge-sealed OSB samples under running water at $31^{\circ}C$ for 8, 24, 72, and 216 h. The results from leached samples were compared with those from the unleached controls. Boron leaching of the modified OSB occurred upon the initial water exposure, and the leaching rate decreased as the leaching time increased. Initial boric acid equivalent (BAE) level, wood species, and sample thickness swelling significantly influenced the leachability. There was no consistent effect of polyethylene glycol (PEG) on zinc borate leaching. The glue-line washing within OSB due to thickness swelling of the test samples under water and decomposition of the borate to form water-soluble boric acid were thought to be two possible causes for the observed leaching. The relationship between assayed BAE and leaching time followed a decaying exponential function for zinc borate treated OSB. From the boron/zinc ratio after each leaching period, boron element in ZB was more or less leachable. The material constant of the regression models allowed comparing the leachability of the modified OSB for various wood species. An unified leaching method for treated wood composite materials is needed.

• 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.

• 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 $Mg(OH)_{2}$.

• Journal of the Korean Chemical Society
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• v.56 no.1
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• pp.47-53
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• 2012

We have investigated the growth kinetics and electronic properties of passive film of zinc in borate buffer solution. The oxide film formed in passivation process of zinc has showed the electronic properties of n-type semiconductor based on the Mott-Schottky equation. And it was found out that the oxide film consisted ZnO and $Zn(OH)_2$ was composed of deep and shallow donors.

• Journal of the Korean Society of Safety
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• v.23 no.4
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• pp.99-104
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• 2008

In this research, magnesium hydroxide as a flame retardant agents and zinc borate as a synergist were mixed with LDPF/EVA blended samples, in order to improve their flame retardancy. We attempted to select the best mixing ratio of the LDPF/EVA blend and the optimum amount of magnesium hydroxide and zinc borate by the comparison and analysis of the flame retardancy, the electrical properties such as the volume resistivity and dielectric loss tangent, and the mechanical properties such as the tensile strength and elongation at break. Particularly, specimen which is the 6phr of zinc borate and 10phr of magnesium hydroxide 70/30phr adding to the LDPF/EVA blended samples has been most excellent in flame retardancy and electrical/mechanical properties.

• Journal of the Korean Wood Science and Technology
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• v.36 no.5
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• pp.1-10
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• 2008

Decay and mold resistance of zinc borate (ZB) and calcium borate (CB) modified oriented strandboard (OSB) from southern mixed hardwood and southern yellow pine was investigated in this study. Brown rot fungus Gloeophyllum trabeum and white-rot fungus Trametes versicolar were used to examine the decay resistance of the OSB. The OSB test specimens were colonized by brown and white rot fungal mycelium in both the brown and white-rot culture bottles after 8 and 12 weeks, respectively. The wood species and fungus type had the significant effects on the decay resistance. Brown rot decay was evident for all untreated southern pine and mixed hardwood controls. The white-rot decay, however, did not show significant weight loss at both species control samples. The incorporation of ZB and CB composites provides suitable protection against brown-and white-rot fungi. No significant weight loss was observed from the borate treated OSB.

• Journal of the Korean Wood Science and Technology
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• v.36 no.5
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• pp.11-23
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• 2008

The mechanical and physical properties of zinc borate (ZB)-modified oriented strandboard (OSB) from southern wood species were investigated in this study. OSB panels treated with ZB were not significantly weaker than the untreated samples in terms of specific modulus of elasticity (SMOE) and specific modulus of rupture (SMOR). ZB showed the negative effect on specific internal bond (SIB) strength, since some of ZB would persist as a powder state on the flake surfaces, thereby reducing the bonding efficiency of the adhesive. The ZB level did not show significant effect on thickness swelling (TS). ZB-modified OSB showed the suitable mechanical and physical properties for the structural wood composites.

• Journal of the Korean Wood Science and Technology
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• v.33 no.4 s.132
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• pp.38-44
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• 2005

This study was carried out to investigate the combustion characteristics of flame retardant treated wood by water-soluble flame retardants which are made from mixture of aqueous solution of monoammonium phosphate, sodium borate and zinc borate. The combustion characteristics for flame retardant treated wood were carried out using thermal analysis (TGA, combustion heat) and flame retardant test (LOI, flame propagation). The results of thermal analysis and flame retardant test are as follows; 1) The sample treated by F4 showed excellent flame retardant effects in almost all of combustion characteristics. 2) From TGA curves, all the samples undergo pyrolysis and oxidation in two main discrete steps. 3) The effect of flame retardant for softwood is higher than those for hardwood, and the combustion heat has decreased with increase of the content of flame retardant. 4) LOI values are almost similar in flame retardant treated wood samples. The range of LOI is from 24 to 30. However, these values are much higher than LOI value of non-treated wood sample. 5) The blended aqueous solution had a final in the range of about pH 8.4, and a slight odor of ammonia.

• Nuclear Engineering and Technology
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• v.53 no.9
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• pp.3058-3067
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• 2021

Sodium zinc borate glasses doped with dysprosium and modified with different concentrations of barium oxide (0-50 mol %) were fabricated using the melting quenching technique. The structural properties of the prepared glass systems were characterized using XRD and FTIR methods. The absorption spectra of the prepared glasses were measured to determine their energy gap and their related optical properties. The density of the glasses and other physical parameters were also reported. Additionally, with the help of Photon Shielding and Dosimetry (PSD) software, we investigated the radiation shielding parameters of the prepared glass systems at different energy values. It was found that an increase in the density of the glasses by increasing the concentration of BaO significantly improved the gamma ray shielding ability of the samples. For practical results, a compatible irradiation set up was designed to check the shielding capability of the obtained glasses using a gamma ray source at 662 keV. The experimentally obtained results strongly agreed with the data obtained by PDS software at the same energy. These results demonstrated that the investigated glass system is a good candidate for several radiation shielding applications when comparing it with other commercial shielding glasses and concretes.