• 한국환경농학회지
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• 제36권4호
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• pp.288-292
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• 2017

BACKGROUND: Silicon tetrachloride reacts with moisture in the atmosphere to generate hydrogen chloride, which affects the environment. Since silicon tetrachloride and its by-products are dispersed in the atmosphere in a short time after the silicon tetrachloride release into the atmosphere, it is difficult to directly assess the extent of environmental impact. In the present study, the exposure test of silicon tetrachloride or hydrogen chloride was examined in order to establish the criterion of the range affected by the silicon tetrachloride release, and the actual crops in the area exposed to silicon tetrachloride leakage were analyzed. METHODS AND RESULTS: For the experiment of exposure to silicon tetrachloride or hydrogen chloride, the leaves of red-pepper and corn were used in glass sealed containers. In the actual accident area, 59 samples from 10 different kinds of crops were collected. The pretreatment of the sample was performed by freezing and grinding, and then extracted using distilled water. The pH and concentration of chloride ($Cl^-$) ion of the extracted solution were measured using pH meter and ion chromatograph, respectively. CONCLUSION: Exposure to silicon tetrachloride caused visible damage, increasing the concentration of chloride ion, and decreasing the pH as well as hydrochloric acid. In the actual crops of the affected area, the tendency was the same as the result of the laboratory test, and the range of influence could be estimated through the concentration of $Cl^-$ ion over 2,000 mg/kg, and the correlation evaluation between the concentration of $Cl^-$ and pH. Therefore, the concentration of $Cl^-$ ion and the correlation between $Cl^-$ and pH would be considered as the factors to estimate the influence range of silicon tetrachloride release.

• 대한화학회지
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• 제41권10호
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• pp.541-546
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• 1997

이산화망간 존재하에서 사염화규소는 1차, 2차, 3차 및 벤질알코올 유도체 뿐 만 아니라 시클로헥산올과 같은 고리형 알코올, 알릴 알코올 등의 염소화반응을 정량적으로 수행할 수 있음을 발견하였다. 먼저 이산화망간이 사염화규소의 반응성이 큰 규소-염소 결합에 삽입되어 불안정한 중간체인 Manganese(IV) oxodichloride를 생성하고 이 중간체는 계속하여 사염화규소와 반응하여 최종적으로 사염화망간을 생성하리라 예상된다. 이렇게 생성되리라 예상되는 화학종들은 모두 반응메카니즘적으로 알코올의 염소화반응에 관여할 수 있음을 알았다. 이 반응은 Thionyl chloride나 삼염화인등을 사용한 고전적인 알코올의 염소화반응에 비하여 많은 장점을 가짐을 알 수 있었다.

• 대한화학회지
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• 제41권10호
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• pp.535-540
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• 1997

탄산칼륨 존재하에서 사염화규소는 1차, 2차, 3차 및 벤질알코올 유도체 뿐 만 아니라 시클로헥산올과 같은 고리형 알코올, 알릴 알코올등의 염소화반응에 효과적임을 알 수 있었다. 탄산칼륨이 사염화규소의 반응성이 큰 규소-염소 결합과 반응하여 생성될 수 있는 불안정한 중간체인 Trichlorosilyloxy carbonylchloride 혹은 최종적으로 평형농도 만큼 소량씩 생성되리라 예상되는 Phosgene은 모두 반응메카니즘적으로 알코올의 염소화반응에 관여할 수 있음을 알았다.

• 한국세라믹학회지
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• 제20권2호
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• pp.166-172
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• 1983

In this study the sillicon-alloyed isotropic pyrolytic carbon was deposited in the tumbling bed from the pyrolysis of propane and silicon tetrachloride and investigated whether the silicon-alloyed isotropic pyrolytic carbon deposited in this study was usable as bionaterial or not. The silicon-allyed isotropic pyrolytic carbon was varied by controlling the process variables such as propane con-concentration and the argon flow rate flowing in to the silicon tetrachloride bubbler at a fixed reaction bed tempera-ture of 120$0^{\circ}C$ a rotation of reaction tube of 40 rpm a bed particle weight of 7.5 g and a total flow rate of 21/min; the propane concentration was varied from 10 to 70 and the argon flow rate flowing into the silicon tetrachloride bubble from 0 to 1000 cc/min. The results show that the silicon-alloyed isotropic pyrolytic carbon was obtained at all conditions investigated, . And then the alloyed silicon content is rangion from 7 to 14.5 wt%. The density and deposition rate of deposited silicon-alloyed isotropic carbon increased axxording to silicon content and propane concentration. And the apparent crystal-size(Lc) of pyrolytic carbon is not changed with silicon content. The density and apparant crystallite size are respec-tively in the range of 1.94 to 2.06 and 20 to 25$\AA$ It is shown that the silicon-alloyed isotropic pyrolytic carbon ob-tained in this experiment is usable as biomaterial.

• 한국가스학회지
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• 제22권4호
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• pp.55-62
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• 2018

지구온난화로 인하여 태양광 발전에 대한 관심이 커지고 있다. 이에 따라 태양전지를 만드는 핵심물질인 폴리실리콘의 수요도 나날이 증가하고 있으며 시장이 커짐에 따라 생산공정에서 크고 작은 사고들이 발생하고 있다. 그 예로 2013년 상주시의 폴리실리콘 제조공장에서 염산이 누출되었고 2014년에는 여수시의 폴리실리콘 제조공장에서 화재가 발생하였으며, 2015년에는 군산시의 폴리실리콘 제조공장에서 STC(Silicon Tetrachloride)가 누출되었다. 이러한 누출 사고들은 사업장 내부에만 영향을 주는 것이 아니라 인근지역까지 영향을 줄 수 있다는 것이 특징이다. 따라서 본 연구에서는 폴리실리콘 제조공정에서 사용되는 위험물질을 파악하고, 최악의 누출 시나리오를 적용했을 때 누출량과 피해범위를 정량적으로 예측하였다. 그 결과 폭발에 따른 피해거리는 726 m로 예측되었고, 독성에 대한 피해거리는 4,500 m로 예측되었다. 그리고 TCS(Trichlorosilane), STC(Silicon Tetrachloride), DCS(Dichlorosilane)가 누출되어 공기 중의 수분과 반응하여 HCl이 생성될 경우 피해거리는 최대 5.7 km까지로 예측되었다.

• Bulletin of the Korean Chemical Society
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• 제9권1호
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• pp.15-17
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• 1988

Titanium tetrachloride is purified using adsorption column packed with activated silica gel. When 120 ml of titanium tetrachloride was passed through an adsorption column filled with 7 g silica gel, iron content in titanium tetrachloride has been reduced from 7 ppm to less than 1 ppm, and aluminum from 46 ppm to 11 ppm, while silicon content being unchanged at about 60 ppm.

• 분석과학
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• 제15권1호
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• pp.87-90
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• 2002

The content of $SiHCl_3$ as a trace impurity in $SiCl_4$ was analyzed by Near IR spectrophotometer with optical fiber. The strong absorption bands of $5345{\sim}5116cm^{-1}$ and $4848{\sim}4349cm^{-1}$ were used for analysis of $SiHCl_3$, and the detection limit of impurity $SiCl_3$ was appeared to be 0.005 ％ in the spectrum. The quantitative analysis by Near IR spectrophotometry showed the analytical possibility of trace impurity in $SiCl_4$ without sample pre-treatment not only in the laboratory but also in the field.

• 통합자연과학논문집
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• 제3권3호
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• pp.133-137
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• 2010

New synthetic route and characterization of alkyl-capped nanocrystalline silicon (R-n-Si) were achieved from the reaction of silicon tetrachloride with sodium/benzophenone ketal reducing agent followed by n-butyllithium. Surface of silicon nanoparticles was derivatized with butyl group. Effect of oxidation of silicon nanoparticle with benzophenone was investigated for their stabilization. Optical characteristics of silicon nanoparticles were characterized by fourier transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy (UV-vis), and photoluminescence (PL) spectroscopy. Butyl-capped silicon nanoparticles exhibited an emission band at 410 nm with excitation wavelength of 360 nm. Average size of n-butyl-capped silicon nanoparticles was obtained by particle size analyzer (PSA) and transmission electron microscopy (TEM). Average size of n-butyl-capped Si nanoparticles was about 6.5 nm.

• 통합자연과학논문집
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• 제4권4호
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• pp.282-288
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• 2011

We describe the synthesis and characterization of silicon nanoparticles prepared by the solution reduction of silicon tetrachloride by lithium naphthalenide and subsequently with n-butyllithium at room temperature. These reactions produce silicon nanoparticles with surfaces that are covalently terminated with butyl group. Reaction with lithium aluminium hydride instead of n-butyllithium produces hydride-terminated silicon nanoparticles. The butyl or hydride terminated silicon nanoparticles can be suspended in hexane and their optical behavior have been characterized by photoluminescence spectroscopy. Stabilization of silicon nanoparticles were investigated upon illumination, indicating that as-prepared silicon nanoparticles are very stable at room temperature for several days.

• 분석과학
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• 제25권6호
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• pp.345-349
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• 2012

Polysilane black powders were synthesized by sonochemical methods from silicon tetrachloride with sodium metal with 37.0% yield. Those black powder materials were found to have fibrous or irregular shapes with round surface. It was found that thermal behaviors of those polysilane black powders were similar to that of hydropolysilanes which was reported earlier. After thermal treatment, black polysilicon was obtained with 57.1% residue yield, and those fibrous or irregular shapes with round surface were intact but lots of small cavities were formed indicating porous structure, and found to be an amorphous state from XRD analysis.