• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.06a
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• pp.333-333
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• 2004

고온의 용융염 매질에서 전해 정련 또는 전해제련에 의해 원하는 물질을 회수하기 위한 공정에 있어서 정확한 산화/환원 전위 측정 및 안정된 전위를 인가하기 위해서는 재현성과 내구성이 확보된 기준 전극이 필요하다. 용융염 매질에서 많이 사용되는 기준 전극은 Ag/AgCl 전극으로서 온도 사이클에 대한 전위의 히스테리시스가 작고 고온에서도 전위가 안정하다. Ag/AgCl 기준전극으로 pyrex 봉 하단부를 수 마이크론 두께의 pyrex 박막으로 제작된 것은 고온 용융염에 접촉시 열 충격, 전극류와 충돌에 의한 물리적 취약성 및 고온의 용융염에 의한 부식과 같은 단점이 있다.(중략)

• Journal of the Korea Academia-Industrial cooperation Society
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• v.6 no.1
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• pp.24-28
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• 2005

A micromachined biochip with a three dimensional silicon chamber was developed for the construction of biosensors. Anisotropic etching was used fur the formation of the chamber on the p-type silicon wafer(100) and then was glued to the Pyrex glass bottom-substrate with pre-deposited platinum electrode. The electrochemical characterization of its Pt electrode and Ag/AgCl reference electrode was investigated.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07a
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• pp.233-236
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• 2003

수소 가스발생을 위한 마이크로 수소 발생기 개발에서 MEMS 공정을 이용하여 기판에 반응 유로를 위해 HAR(High Aspect Ratio) 구조물을 형성하고 Ru(ruthenium) 박막을 증착하여 수소 발생량을 측정하였다. Pyrex glass 기판상에 sand blast 방법으로 반응 구조물을 만들었으며, 그 위에 sputter system을 이용하여 Ru 박막을 $5500{\AA}$었다. 수소 발생량은 촉매 박막이 증착된 기판 재질과 기판의 표면 상태 그리고 마이크로 수소 발생기에 두께로 증착하였다. 반응 구조물의 전체 크기가 가로 2.0 cm, 세로 2.0cm의 면적에서 약 12.3 ml/min의 수소가 측정되 형성한 구조물의 형상에 의존하였다. Pyrex glass 기판을 사용하여 HAR로 반응 구조물을 형성한 경우에 단위 면적당 Ru 박반응 막의 반응 표면적이 증가되어 기존에 구조물을 형성하지 않은 평면 기판에 비교하여 약 5.5배 이상의 수소 발생이 증가하였다.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.7 s.172
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• pp.71-78
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• 2005

The purpose of this study is to suggest a hyperfine maskless writing technique by using the nanoindentation and HF wet etching technique. Indents were made on the surface of Pyrex7740 glass by the hyperfine indentation process with a Berkovich diamond indenter, and they were etched in $50\;wr\%$ HF solution. After etching process, convex structure was obtained due to the deformation-induced hillock phenomena. In this study, effects of indentation process parameters (etching time, normal load, loading .ate, hold-time at the maximum load) on the morphologies of the indented surfaces after isotopic etching were investigated from an angle of deformation energies. Finally, sample characters were written to show the possibility of the application.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1996.11a
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• pp.338-341
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• 1996

Anodic bonding is a key technology for micromechanical components. The main advantages of this method can be formed in a batch process, over large areas, and is permanent and irreversible. In this paper, the bonding was performed at temperatures ranging from 300 to 450 $^{\circ}C$, voltages 400 to 1000 V, and times 10 to 30 minutes. The sizes of the Si and the Pyrex #7740 glass were 6 mm $\times$6 mm, respectively. Bonding processes and voids were observed by the optical microscope, and the composition of the anodic bonding interface was analyzed by the SIMS. Optimum condition of the anodic bonding was at temperature above 40$0^{\circ}C$ without regard to voltage.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05a
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• pp.33-39
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• 1998

기존 가압형 경수로에서 전체 반응도가의 상당부분을 제어하고 있는 붕산수를 사용하지 않고 가연성독봉 및 쟤어봉을 확대 사용하는 전략으로 1300MWe급 차세대원자로(KNGR)를 대상으로 무붕산 노심 개념설계를 수행하였다. 가연성독봉으로는 기존 PYREX 독붕의 독물질을 농축한 농축 PYREX 독봉을 도입하여 주기초 반응도 제어효과 및 전 주기동안 평평한 잉여반응도 유지에 매우 효과적인 결과를 도출하였다. 또한, 무붕산 노심이 필연적으로 갖게되는 축방향 출력분포의 노심 하단부치중현상을 제어하기 위하여 부분장 제어봉(Part Length Control Red)을 보조적으로 사용, 매우 간단한 형태의 핵연료집합체 축방향 zoning 설계를 수행하였다. 부분장 제어봉의 사용으로 모든 핵연료집합체를 축방향으로 zoning 하지 않고도 축방향 출력분포를 효과적으로 제어할 수 있었다. 제어봉으로는 큼 제어봉가를 확보하기 위하여 B$_4$C를 재질로하는 Checkerboard 형태의 제어봉 설계를 수행하였고, 효과적인 제어봉 운영을 통하여 무붕산 노심의 잉여반응도 및 출력분포 제어가 가능하였으며 제어봉이 운전중에 상당부분 삽입될지라도 약 7%$\delta$p 의 충분한 운전정지 여유도를 확보할 수 있다는 가능성을 확인할 수 있었다.

• Korean Journal of Optics and Photonics
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• v.1 no.2
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• pp.162-168
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• 1990

Two ZnSe loss plates were installed in the resonator of waveguide CO2 laser which consisted of Pyrex capillary tube in order to change the internal loss. By rotating the loss plates, the output variations with the internalloss was measured on various discharge conditions. The variations could be explained by the Rigrod theory. and the saturation power and the unsaturated gain coefficient were determined by fitting of the experimental results. It was found that the saturation power increased while the unsaturated gain coefficient reduced as the discharge current or the gas flow rate increased.reased.

• Proceedings of the Korean Vacuum Society Conference
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• 2004.02a
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• pp.129-130
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• 2004

• Applied Biological Chemistry
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• v.7
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• pp.15-19
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• 1966

In order to investigate the stability of the major component of malathion E.C. product, dimethyl S-(1, 2-dicarboxyethoxyethyl) dithiophosphate, toward the quality of glasswares as container, the amount of extractable inorganic components, change of pH and decomposition of the major component of the product were examined during the storage in brown-colored bottles of 100 ml. volume from 3 different companies in comparison with that in a Pyrex flask. 1. Malathion E.C. product was put in three containers A,B and C, and any changes occurring in storage were analyzed at three intervals of 60, 120 and 240 days. 2. It was shown that the amounts of Si, Mg, K, Ca, and Na extracted during these periods of storage differed markedly depending on the qualify of container. Container A revealed ten times higher extraction of Na and Ca than container B and C in a 8-month period. 3. Three commercial containers revealed the shift of pH from 6.5 to alkaline reaction in the storage whereas the Pyrex flask did not show any detectable change. In particular, the pH in container A changed to 9.2 in 60 days and 9.9 in 240 days. 4. The decomposition of malathion was the greatest in container A which showed the decomposition of 7.37% in 240 days. On the other hand, 0.5% was decomposed in the Pyrex flask. 5. The decemposition of malathion had a high correlation with the change of pH of water· in the same container, $r^2$ being 0.899. From the above results, it is concluded that about 10% of malathion E.C. product is decomposed in a year due to the alkaline metallic salts extracted from the container when it is stored in glassware bottles of lower quality.

• Elastomers and Composites
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• v.42 no.1
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• pp.20-31
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• 2007

Material characteristics and lifetime evaluation are very important in design procedure to assure the safety and reliability of the rubber components. In this paper, the NBR compound was prepared by sulfur-cure system, and was used in predicting the lifetime of rubber gasket made by the compound. The accelerated material aging was investigated at different temperatures at 120, 140 and $160^{\circ}C$ and aging time from 3 hours to 600 hours at 5, 6, 7 vol %. of $H_2SO_4$ concentrations The rubber strips were placed in acid solution using pyrex g1ass tube. Both ends of pyrex g1ass tube were sealed to avoid evaporation of solution during heating at given time. The material test and accelerated acid-heat aging test were carried out to predict the useful life of NBR rubber gasket for a fuel cell stack. In order to investigate the effects of acid-heat aging on the properties of the NBR, tensile strength, elongation at break, hardness and crosslink-density were measured. The tensile strength decreases as the $H_2SO_4$ concentrations and temperature increase. Results were evaluated using Arrhenius equation.