• 한국환경보건학회지
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• 제30권5호
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• pp.358-365
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• 2004

The photocatalytic oxidation of Rhodamine B(RhB) was studied using photocatalytic reactor filled with module of quartz tube. Module of quartz tube consisted of small quartz tube (inner diameter, 1.5 mm; outer diameter, 3 mm) bundle coated with powder $TiO_2$ and uncoated large quartz tube (inner diameter, 20 mm; outer diameter, 22 mm). Two 30 W germicidal lamp was used as the light source and the reactor volume was 0.5 l. The effects of parameters such as the coating materials and numbers, initial concentration, $H_{2}O_2$ dose and metal deposition (Ag, Pt and Fe) and simultaneous application of $H_{2}O_2$ and metal deposition. The results showed that the initial reaction constant of quartz module coated with powder $TiO_2$ was higher 1.4 time than that of the $TiO_2$ sol and optimum coating number is twice. In order to increase reaction rate, simultaneous application of photocatalytic and photo-fenton reaction using Fe coating and dose $H_{2}O_2$ dose increased reaction rate largely.

• 공학논문집
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• 제3권1호
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• pp.223-233
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• 1998

고상반응식을 이용한 석회와 석영과의 수열반응속도 및 반응메카니즘에 관하여 연구하였다. 출발물질로 석영과 수산화칼슘 CaO/$SiO_2$몰비 0.8-1.0로 혼합하고 $180-200^{\circ}C$, 0.5-8시간동안 포화증기압하에서 오토클레이브로 수열반응을 행하였다. 수열반응속도는 총 석회의 양과 총 석영의 양에 대한 미반응 석회의 양과 미반응 석영의 양의 비로 구하였다. 반응속도는 Jander의 식 $[1-(1-\alpha)^{1/3}]^N=Kt$를 이용하여 얻은 결과, 석회의 반응속도는 N=1로서 주로 용해속도에 의해 지배되고 석영의 반응속도는 $N\risingdotseq2$로서 확산에 의해 주로 지배된다. 규산칼슘수화물계의 수열반응속도는 반응물 입자주위에 형성된 생성물층을 통한 물질전달에 의해 율속되는 것으로 추정되고 전체 수열반응의 속도식은 대략 $N=1-2$로서 경계층으로부터 확산에 의해 율속과정으로 전환된다.

• 동굴
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• 제78호
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• pp.9-15
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• 2007

The materials showing high structure dispersion with functional properties were developed on the quartz base and those were obtained by mechano-chemical reaction technology. Depending on the processing conditions and subsequent applications the materials produced by mechano-chemical reaction show concurrently magnetic, dielectric and electrical properties. The obtained magnetic-electrical powders classified by aggregate complex of their features as segnetomagnetics, containing a dielectric material as a carrying nucleus, particularly the quartz on that surface one or more layers of different compounds were synthesized having thickness up to 1050nm showing magnetic, electrical properties and others. The similarity of the structure of surface layers of quartz particles subjected to mechano-chemical processing and nano-structure cluspol (clusters in a polymer matrics) material was alsoconfirmed by the fact that the characteristics of ferromagnetic quartz of insulating nano-composite powder were changed with time, after its preparing process was completed.

• 한국세라믹학회지
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• 제23권1호
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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.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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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.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2004년도 SMICS 2004 International Symposium on Maritime and Communication Sciences
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• pp.113-116
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• 2004

The materials showing high structure dispersion with functional properties were developed on the quartz base and those were obtained by mechano-chemical reaction technology. Depending on the processing conditions and subsequent applications the materials produced by mechano-chemical reaction show concurrently magnetic, dielectric and electrical properties. The obtained magnetic-electrical powders classified by aggregate complex of their features as segnetomagnetics, containing a dielectric material as a carrying nucleus, particularly the quartz on that surface one or more layers of different compounds were synthesized having thickness up to 10~50 nm showing magnetic, electrical properties and others. The similarity of the structure of surface layers of quartz particles subjected to mechano-chemical processing and nano-structure cluspol (clusters in a polymer matrics) material was also confirmed by the fact that the characteristics of ferromagnetic quartz of insulating nano-composite powder were changed with time, after its preparing process was completed. The magnetic permeability of the sample was decreasing within first two months down by 15~20 %. Then, the magnetic characteristics were almost stabilized steadily and continuously. The observed changes were related with defective structure of the particles, elastic stress relief, and changes of electron density and magnetic moment in deformation zones. This process of stabilization of the investigated properties could be intensified by the thermal annealing heat treatment in short time period of the nano-composite quartz powders at the temperature ranges of 100~15$0^{\circ}C$.

• 한국산업융합학회 논문집
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• 제10권3호
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• pp.179-185
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• 2007

Quartz glass are used in semiconductor industries as the reaction furnace, wafer carrier and accessaries. During the process the quartz glass received compression by direct contact with other quartz glass ware and metal as the form of weight itself and vacuum pressure and fatigue by vibrations caused by process. Even as the other ceramic materials quartz glass have high compressive strength but often there happened crack and breakage of quartz glass resulted in a great damage in the process. In this paper investigation will be carried out on fracture behavior of quartz glass under local load to give guideline to prevent unintended fracture of quartz glass.

• 공업화학
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• 제31권6호
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• pp.697-700
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• 2020

본 연구에서는 석영 나노 결정의 합성과 특성 분석을 진행하였다. 비정질 실리카 나노 입자 전구체가 용해된 용액을 섭씨 250도 온도와 자가 압력의 온건한 열수 반응 하에서 석영 나노 결정을 성공적으로 합성하였다. 합성된 나노 결정의 화학적 조성과 구조 분석을 시행하였다. 알파 석영의 특징적인 고결정질 상의 나노 구조를 가지는 석영 나노 결정의 평균 크기는 반응 시간에 따라 407.5 에서 826.2 nm까지 비교적 좁은 범위에서 조정될 수 있음을 발견하였다. 본 연구를 통해 발견된 석영 나노 입자는 광전자, 센서, 및 충전식 배터리 소자의 기술 응용에 매우 중요한 잠재적 용도가 있을 것으로 사료된다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.123-126
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• 2001

Multiwalled carbon nanotubes were massively produced by the catalytic reaction of C$_2$H$_2$ - Fe(CO)$\sub$5/ mixture at 750 - 950$^{\circ}C$ in a quartz tube reactor and over quartz substrates. Well-aligned MWNT array grows perpendicular to the quartz tube reactor and the quartz substrates at an average of 60 nm in diameter and up to several thousands of micrometers in length. This method does not require any pretreatment of substrates and CNTs are grown at atmospheric pressure. It could be suitable for mass production of multiwalled nanotubes. Scanning electron microscope and transmission electron microscope images of the nanotubes deposited on the substrates allowed us to monitor the quality of MWNTs grown under different operating conditions.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.2
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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.