• Journal of the Korean Chemical Society
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• v.31 no.3
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• pp.271-279
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• 1987

A nitrate ion-selective PVC membrane electrode based on ammonia modified bakelite A-Ni$(NO_3)_2$ complex as ion exchanger was prepared. The electrode gave a linear response with a Nernstian slope of 60mV per decade within the concentration range $1{\sim}10^{-4}$ M $KNO_3$ but nonresponse to hydrogen ion and multivalent anions. The selectivity, response time and life time of the electrode were investigated and it was found that the electrode exhibited good selectivity for four univalent anions ($Cl^-,\;Br^-,\;I^-,\;{ClO_4}^-$). Analytical application to the determination of nitrate were also studied.

• Journal of the Korean Chemical Society
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• v.36 no.3
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• pp.383-392
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• 1992

(Bakelite-A)-(2,2'-Bipyridine)-Ni(Ⅱ) Nitrate complexes were tested as ion exchanger for nitrate ion-selective electrode. The experimentally observed selectivity and electrode characteristics were relatively in good agreement with the exchanger lipophilicity in the membrane phase. Based on chemical composition, mechanisms for exchange with nitrate ion and internal electrical conduction were postulated. Analytical application to the determination of nitrate were studied.

• 전기의세계
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• v.26 no.6
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• pp.78-85
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• 1977

This paper studies flashover voltage and surface corona loss of A.C and D.C in the mixed gas of air and SF$_{6}$ for solid insulators P.V.C, arcylic, glass and bakelite in two cases. In one case, those solids are covered with transformer oil and the other case, those solids are not covered with it. 1) The flashover voltage for each solids in SF$_{6}$ is more than three times compared with that in the air. The flashover voltage for P.V.C is the highest and then arcylic, glass, bakelite in a decreasing order. 2) The more the amount of SF$_{6}$ in the mixing ratio, the less corona loss. The P.V.C shows the least amount of corona loss and the bakelite the largest. 3) Compared with the corona loss of positive polarity and the negative polarity, the former has less corona loss than the latter. 4) The more the number of flashover discharge, the less insulation of each solids, but in case of bakelite, insulation almost vanishes after a couple of discharge. 5) When each insulator is covered with transformer oil, the flashover voltage generally increases and the corona loss decreases.eases.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1359-1360
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• 2007

In this paper, it is described the characteristics comparison of LV insulated materials contaminated by the salt vaporization and the particulates. The contact angle of normal PVC is measured $75^{\circ}$ but its of PVC contaminated by the salt vaporization for 500 hours is measured $63^{\circ}$. The contact angle of normal bakelite is measured $66^{\circ}$ but its of bakelite contaminated by the salt vaporization for 500 hours is measured $44^{\circ}$. And the contact angle of normal acrylic resin is measured $65^{\circ}$ but its of acrylic resin contaminated by the salt vaporization for 500 hours is measured $60^{\circ}$. In the surface of insulated materials contaminated by the particulate, the contact angle is decreased. The surface of bakelite is not good as an insulator.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2004.09a
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• pp.135-144
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• 2004

• Journal of Power System Engineering
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• v.16 no.1
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• pp.19-23
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• 2012

This thesis is the result of conducting an analysis to find the solution to the phenomenon of power stoppage due to the disconnection of a CT (Current Transformer) because of vibration. The CT which measures the most essential current is used in power industries as part of a generator protection relay. When it comes to the bottom plate of a CT, nonconductor; such as bakelite and laminates; these material elements should be used because it is impossible to utilize the conductor when measuring the current of a generator which carries a high current if you use other materials. These nonconductor's material properties are irregular and interpretation errors often occur because the weight is light. In addition, since the change of dynamic characteristics which are related to the temperature often occur, it is important to match the real situation by considering an error of interpretation rather than selecting the quality of the material. Lastly, the conclusion that the study drew is that it is possible to avoid the resonance by utilizing three changes to the components to solve the problem concerning the high vibration which is caused by non-conductive objects. These changes are the most crucial points in this thesis: First, material changes to the Plate. Second, weight changes to the Coil. Third, thickness changes to the Plate.

• Proceedings of the KIEE Conference
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• 1998.07a
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• pp.334-336
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• 1998

This paper deals with the problem of the magnetizing yoke fixture. The experimental test has been performed using the yoke fixture made of bakelite as well as ferromagnetic. The magnetizing current is the most essential criterial factor for delivering the impulse energy to the magnetized material, i.e ferrite core. The yoke of nonferromagnetic has shown its better performance in experimental results as well as in the finite element analysis.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.6
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• pp.44-49
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• 2013

This study investigates the surface discharge characteristics of solid insulators by varying their materials, their shapes, and the dew-point of dry-air. The methodology of this study is that a quasi-uniform field is first applied to a test chamber. Then, the chamber is filled with dry-air as an insulation gas which pressure is varied from 1 to 6atm while applying an AC voltage to the chamber. The used solid insulators are teflon, polycarbonate, and bakelite. As the dew-point is lower and the pressure of dry-air is higher, the flashover voltage of all solid insulators increases more. When each characteristic of the solid insulators is compared under the same gas pressure, the flashover voltage of teflon is the highest. Then, the flashover voltage of polycarbonate is higher than that of bakelite. Moreover, it is observed that the flashover voltage increases as the diameter and the thickness of each solid insulator become larger and thicker, respectively. However, the thickness of the solid insulators is more critical for increasing the flashover voltage than their diameter.

• Journal of radiological science and technology
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• v.5 no.1
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• pp.35-43
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• 1982

The authors surveyed the cassettes in 10 general hospitals and compared in experimentation on performances of 6 kinds of cassettes manufactured with several materials in order to discover the present condition and performance of the cassettes being used at present. And the authors got the following results. 1. In distribution of the cassettes in use, Okamoto's(Japan), Picker's and Titan's(U.S.A.) were more than others classified by the manufacture. The rate of using high speed was 72.0%, par speed 28.0% classified by types of intensifying screens in the cassettes and the rate of the year in use for $4{\sim}5$ years was 40.0%, $6{\sim}7$ years 24.0% classified by the years in use. 2. The results of the screen-film contact test were that tile ordinary was 42.7%, the good 36.0%, and the poor 21.3%. 3. The results of the test for light leakage were that fogged area appeared on 1 side or more in 84.0% films. 4. In Aluminum equivalents of front plate, the cassettes with a front plate consisting of carbon fiber were fewest, and the ones of bakelite and aluminum were fewer in order 5. In compared results of the exposure dosage for same density of the films, the exposure of the cassettes used carbon fiber for the material on the front plate was smallest and bakelite, auminum was smaller in order.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.12
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• pp.1360-1366
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• 2008

This paper proposes a printed yagi-antenna available at 2.45 GHz, for the remote-management system of the underground equipment. To improve the solidity and waterproof property, the proposed antenna is coated with bakelite. The manufactured antenna is operated at $2.15{\sim}2.52\;GHz$, whose gain measures 10 dBi. These results are a little different from those of the simulated antenna, but the trend is totally similar. Developed antenna is expected to be useful in the underground facility.