• 제목/요약/키워드: quartz

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SHS of Oxide Systems Based on MCR of Quartz Modified by Organometallic Compounds

  • Soh, Dea-Wha;Tlek, Ketegenov;Z.A., Mansurov
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.07b
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    • pp.666-669
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    • 2002
  • The differences of the effects of mechanical substance pre-activation in the mills with divers force effect schemes on the self-propagating high temperature synthesis (SHS) of the $SiO_2$ + 37.5% Al system were investigated. The power saturation of activated material state are estimated referring on the variations of dilatometry curve paths. The effects of activation time on the temperature of sample self-ignited in the furnace, combustion temperature and completeness of the quartz reaction with aluminium were determined. The enhancing effects of organic modifiers of quartz particle surfaces on the further SHS synthesis development were shown.

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Frequency Agile Properties of Microstrip Antenna Using Quartz (안테나의 주파수 특성에 관한 연구)

  • Yun, Chang-Jin;Ha, Yong-Man;Hwang, Hyun-Suk;Song, Joon-Tae
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.07b
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    • pp.715-718
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    • 2002
  • This paper investigated that resonant frequencies of microstrip patch antenna were agile when piezoelectric materials were used as the antenna substrates. When the bias is applied on them, thickness of the substrate is varied according. to the piezoelectric phenomenon. The microstrip patch antenna using Quartz substrate was fabricated and designed by Ensemble v 7.0 simulator. We fabricated the microstrip antennas using Quartz(Y-cut) as its substrate. When the operating frequencies of the microstrip antenna were 7.045GHz, 7.773GHz 8.18GHz the frequency shifts versus electric field, Emax=4[kV/cm], were 21MHz, 26MHz and 28MHz, respectively.

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Electric Properties of LB films Using Impedance Analysis of Quartz Crystal (수정진동자의 임피던스 분석을 이용한 LB막의 전기적 특성)

  • Jin, Chel-Nam;Park, Jae-Chul;Kwon, Young-Soo
    • Proceedings of the KIEE Conference
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    • 1998.11c
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    • pp.878-880
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    • 1998
  • Quartz crystal in contact with viscoelastic medium is described directly in terms of the electrical equivalent circuit of the system. Stearic acid is used as viscoelastic medium and deposited on the surface of quartz crystal using the Langmuir-Blodgett(LB) method. Impedance properties of quartz crystal coated with LB films which were investigated and the possibility of applying the technique to chemical sensing introduced.

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The Influence of Alkaline Impurity K Content on Bubbles of Quartz Glass

  • Yeom, Ho Jong;Im, Hangjoon;Lee, Joo Ho;Song, Jun Baek;Kim, Yeong Joo
    • Journal of the Korean Ceramic Society
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    • v.54 no.4
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    • pp.298-302
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    • 2017
  • To investigate the influence of alkaline impurity K content on bubbles of quartz glass, samples were prepared based on $SiO_2$ sand with differing amounts of potassium hydroxide solution added by electric fusion. Bubble properties such as number, diameter and bubble fraction were determined using a stereoscopic microscope. The results of the observations indicated that an alkaline impurity content of 100 ppm had a good effect on bubble decline in quartz glass. The effect on OH was investigated by FTIR(Fourier transform infrared spectroscopy).

Characteristics on Magnetism Treatment of Quartz Powder (천연산 석영 분말의 자성처리 특성)

  • Soh, Dea-Wha;Cho, Yong-Joon;Soh, Hyun-Joon;Jung, Jong-Hyun
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.07b
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    • pp.1241-1244
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    • 2003
  • The materials showing high structure dispersity are developed on the natural quartz base and they are obtained by mechano-chemical technology. Depending on the processing conditions and subsequent applications the materials produced by mechano-chemical reaction (MCR) show concurrently magnetic, dielectric and electrical properties. The obtained magnetic-electrical powders classified by aggregate complex of their features as segnetomagnetics, contain a dielectric material as a carrying nucleus, particularly the quartz on that surface one or more layers of different compounds are synthesized having thickness up to $10{\sim}50nm$ and showing magnetic, electrical and other properties.

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Syntheses of SiC and $SiC-Si_3N_4$ Powder from Jecheon Quartz (제천규석으로부터 SiC 및 $SiC-Si_3N_4$계 분말 합성)

  • 이홍림;배철훈;문준화
    • Journal of the Korean Ceramic Society
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    • v.23 no.1
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    • pp.67-73
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    • 1986
  • SiC and $SiC-Si_3N_4$ powder were synthesized via the carbiding and carbiding-nitriding reaction of Jecheon quartz respectively using graphite as a reducing agent. $\beta$-SiC+($\alpha$+$\beta$)-$Si_3N_4$ composite was obtained by the carbiding-nitriding reaction of Jecheon quartz-graphite mixture at 1, 35$0^{\circ}C$ in $H_2$ atmosphere. $\beta$-SiC+($\alpha$+$\beta$)-$Si_3N_4$ composite was obtained by the carbidint-nitriding reaction of Jecheon quartz-graphite mixture at 1, 35$0^{\circ}C$ in $N_2-H_2$ atmosphere. The ratio of $\beta$-SiC+($\alpha$+$\beta$)-$Si_3N_4$ content in a produced composite could be controlled by adjusting the reaction time and gaseous mixture.

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Frequency Agile Properties of Microstrip Antenna Using Quartz (Quartz를 이용한 마이크로스트립 안테나의 주파수 특성에 관한 연구)

  • Ha, Yong-Man;Oh, Seung-Jae;Woo, Hyoung-Gwan;Song, Joon-Tae
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11b
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    • pp.488-491
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    • 2001
  • This paper investigated that resonant frequencies of micro strip patch antenna were agile when piezoelectric materials were used as the antenna substrates. The resonant frequencies of the micro strip antenna using the piezoelectric substrate. The micro strip patch antenna made of Quartz substrate was designed and fabricated by Ensemble v 7.0 simulator. The experimental problem was compensated by Ensemble v 7.0

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A length dependance of monolayer films of long-chain fatty acids (장쇄지방산의 길이에 따른 단분자막의 특성 변화)

  • 구창권;김무군;송경호;박태곤
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1996.05a
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    • pp.38-42
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    • 1996
  • The pressure-area isotherm of monolayer at the air-water interface were obtained and the LB films were fabricated onto a quartz slides and quartz crystal by conventional Langmuir-Blodggett(LB) method. The UV absorption spectra of Langmuir-Blodggett(LB) film on quartz slides and spectrum of monolayer formed on quartz crystal have been measured. The photoisomerization of the long-chain fatty avid containing azobenzene were obtained by the application of UV and visible light. The reversibility of photoisomerization were more clear difference when the number of C$\_$n/ increased. At the pressure-area isotherms, the value of surface pressure increment were decreased when the number of C$\_$n/ increased, A surface pressure of 20mN/m was obtained as a proper one for a film deposition. The photoisomerization at LB films were also obtained by application of UV and visible light. So the LB film of long-chain fatty acid containing azobenzene has possibility to being applies to functional molecular devices such as photomemory and light switching.

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WTP UV Disinfection System (국내하수처리장 자외선소독조 운영실태 및 기술동향)

  • Lee, J.Y.;Kim, Y.T.;Lee, T.J.
    • 유체기계공업학회:학술대회논문집
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    • 2005.12a
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    • pp.126-132
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    • 2005
  • UV disinfection system allows the disinfection of municipal and industrial water and wastewater without the use of expensive chlorination and dechlorination techniques, labor intensive equipments In traditional ultraviolet systems the UV lamps are seperated from water by quartz sleeves. quartz is one of. the few materials that is virtually transparent to UV light, the UV lamp is placed inside the Quartz sleeve. UV light from the lamp is passed through the quartz and into the water, thereby providing disinfection. In fluoropolymer tube-used non-contact UV systems, the water flows through fluoropolymer plastic tubes. banks of UV lamps surround these tubes such that each tube gets exposed to ultra violet light from all sides. in non-contact design the lamps operates at almost constant temperature. this design is extremly efficient in the utilization of UV energy and superior to conventional contact- systems.

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Effect of Quartz Porphyry Supplemented Diet on Mineral Content in Tissues of Common Finch (맥반석 첨가 식이가 십자매 조직의 무기질함량에 미치는 영향)

  • 차재영;조영수;임정부;김대진
    • Journal of Life Science
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    • v.10 no.6
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    • pp.543-547
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    • 2000
  • Quartz porphyry (QP) on the contents of mineral tissues of male common finch by feeding the basal diet (Control group) containing 3.0% QP (QP group) for 14 days was studied. The relative weight (mg/10 g body weight) of kidney and gizzard in the QP group were higher and lower than in the control group, respectively. However, the relative weight of liver and heart were not significantly different in the both groups. The mineral contents of liver, kidney, heart and gizzard were significantly higher in common finch fed with the diet containing quartz porphyry than that of control diet. The major minerals of these tissues were P, Ca and Fe.

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