• 한국세라믹학회지
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• 제52권3호
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• pp.192-196
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• 2015

Low soda alumina powder was fabricated using silica (${\alpha}$-quartz) as an agent for removing soda components in the alumina. Quartz powder 2 mm in size was added to aluminum hydroxide obtained through the Bayer process, and then the mixture was heated at various temperatures. Finally, the heat-treated powders were sieved for classification. In this study, the effects of the quartz amount and heating temperature on the mechanism of removing soda were examined. A minimum soda content of 0.005 wt% was observed at the conditions of 15 wt% quartz (based on $Al(OH)_3$ amount) heat-treated at $1600^{\circ}C$ for 8 h. The soda components, such as $Na_2O$, NaOH, and $Na_2CO_3$, in alumina were ionized and activated at high temperature, and this facilitated the reaction with quartz silica and alumina producing nepheline. The advantages of using quartz include low iron content and low cost in comparison with the conventional de-soda process using chamotte, another silicate mineral.

• 한국산학기술학회논문지
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• 제5권2호
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• pp.98-102
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• 2004

단일이온교환 프로세스를 도입하여 soda-lime-silicate 유리에 있어서의 이온교환 거동 및 물성변화를 관찰하였다. 온도 및 시간 변화에 따라 K/sup +/ 이온의 침투깊이, 이온교환량은 증가하였으며, 이에 비례하여 밀도, 굴절률도 증가하는 경향을 보였다 이온교환 과정에서 생성된 비가교 산소로 인하여 400nm에서 흡수 현상이 관찰되었으며, 열팽창계수는 구조의 치밀화와 이력현상에 영향을 받았다.

• 한국세라믹학회지
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• 제52권2호
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• pp.133-136
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• 2015

The outward diffusion of $Na^+$ ions in iron-bearing soda lime silicate glass via oxidation heat treatment before the ion exchange process is artificially induced in order to increase the amount of ions exchanged during the ion exchange process. The effect of the addition process is analyzed through measuring the bending strength, the weight change, and the inter-diffusion coefficient after the ion exchange process. The glass strength is increased when the outward diffusion of $Na^+$ ions via oxidation heat treatment before the ion exchange process is added. For the glass subjected to the additional process, the weight change and diffusion depth increase compared with the glass not subjected to the process. The interdiffusion coefficient is also slightly increased as a result of the additional process.

• Nuclear Engineering and Technology
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• 제8권2호
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• pp.69-76
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• 1976

핵연료 재처리 과정이나 원자력발전소에서 대량으로 발생되는 비교적 반감기가 긴 핵종들(Sr-90, Ru-106, Cb-137, Ce-144)의 화학응집제와 국산점토 광물(montmorillonite)에 의한 제거 효율을 결정하기 위해 본 실험이 수행되었다. Phosphate process는 Ce-144의 제거에 있어서 99.5% 이상의 극히 좋은 효율을 나타냈고, lime-soda process는 Sr-90에 대하여 93%의 높은 제거율을 보였으며, Cs-187에 대해서는 copper-ferrocyanide가 제거율 99%의 매우 적절한 화학 응집제임을 나타냈다. Phosphate나 lime-soda process에서 가장 좋은 제거효율은 PH 11 이상에서 얻어졌다. 그리고 NaCl로 처리된 montmorillonite가 방사성 핵종들은 제거하는데 있어서 natural montmorillonite 보다 향상된 제거 효율을 보여주었다.

• 펄프종이기술
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• 제48권3호
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• pp.44-50
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• 2016

As a raw material for pulp and paper industry, Moso bamboo, Timber bamboo and Henon bamboo pulps were prepared by soda or soda-anthraquinone(Soda-AQ) pulping process. Soda-AQ pulp yields was higher in Henon bamboo (43.2%) than in Moso bamboo or Timber bamboo (32.7-39.2%), but quite lower than hardwood species. In Kappa number comparison, Henon bamboo pulp showed lower (16.6) with 50 min cooking to $170^{\circ}C$ than that of Moso bamboo (22.8) and Timber bamboo (18.9) with 90 min cooking to $170^{\circ}C$. Fiber length of Timber bamboo soda pulp had higher (1.46 mm) than that of Moso bamboo or Henon bamboo (1.18-1.36 mm). All three bamboo pulps showed longer average fiber length than commercial hardwood pulp. With higher pulp yield and lower Kappa number, Henon bamboo is better raw material for pulp than Moso bamboo and Timber bamboo.

• 대한화학회지
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• 제56권2호
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• pp.257-263
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• 2012

The selection of suitable delignification conditions and optimization of process variables is crucial to the successful operation of chemical pulping processes. Soda pulping of Carpolobia lutea was investigated, as an alternative raw material for pulp and paper production. The process was optimized under the influence of three operational variables, namely, temperature, time and concentration of cooking liquor. Equations derived using a second - order polynomial design predicted the pulp yield and lignin dissolution with errors less than 8% and 11% respectively. The maximum variations in the pulp yield using a second order factorial design was caused by changes in both time and alkali concentration. Optimum pulp yield of 43.87% was obtained at low values of the process variables. The selectivity of lignin dissolution was independent of the working conditions, allowing quantitative estimations to be established between the pulp yield and residual lignin content within the range studied.

• 한국포장학회지
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• 제26권1호
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• pp.1-9
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• 2020

We evaluated the applicability of baking soda, charco'al, coffee, and green tea as a natural deodorant in Kimchi packaging. Moreover, to evaluate the potential usage of these deodorants in packaging materials and confirm their applicability in high-temperature melt-extrusion processing, the thermal stabilities of the deodorants were investigated, and heat-treated deodorants were evaluated in terms of the deodorizing function compared with non-treated deodorants. Aroma patterns were decreased after deodorizing treatment with all-natural deodorants. Dimethyl disulfide, methyl trisulfide, and diallyl disulfide, the most significant odorous Volatile organic compounds (VOCs) of Kimchi, decreased after treatment with the deodorants. In particular, baking soda and charcoal showed the highest efficiency in removing odorous compounds and VOCs from Kimchi, even after high-temperature processing. The acetic acid removal rates for both baking soda and charcoal were 99.9±0.0%. The heating process increases the deodorizing effects of baking soda. Sensory evaluation results showed that there is a significant increase (p < 0.05) in the overall preference for Kimchi samples packaged with charcoal and baking soda. This study provides useful information for the deodorization effects of natural deodorants for Kimchi smell and their applicability for packaging materials.

• 자원리싸이클링
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• 제21권6호
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• pp.65-73
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• 2012

탈질용 선택적 촉매 환원(SCR) 촉매는 화력발전소의 탈질 시스템에서 발생한다. 폐 SCR 촉매로부터 바나듐 및 텅스텐과 같은 유가금속을 회수하기 위한 공정은 소다배소 및 수침출 법으로 이루어진다. 본 연구에 사용된 폐 SCR 촉매는 $V_2O_5$ 1.23 %, $WO_3$ 7.73 %를 함유하고 있다. 소다배소 공정은 바나듐과 텅스텐 화합물을 수용성의 물질로 전환시켜 주는 역할을 하며, 실험은 $Na_2CO_3$ 첨가량 5 당량, 배소온도 $850^{\circ}C$, 배소시간 120 분, 폐촉매 입자크기 $54{\mu}m$의 조건에서 수행하였다. 소다배소 실험 이후 배소산물을 사용하여 수침출 실험을 수행하였다. 침출실험을 위한 배소산물은 $-45{\mu}m$의 입자크기로 분쇄하였으며, 수침출 실험조건은 침출온도 $40^{\circ}C$, 침출시간 30 분, 광액밀도 10 %이다. 소다배소 및 수침출 실험결과, 바나듐 46 %, 텅스텐 92%의 침출율을 얻었다.

• 펄프종이기술
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• 제47권6호
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• pp.73-80
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• 2015

Corn stalk is the lignocellulosic biomass, which remain as leftover after harvesting. To use the corn stalk as raw material for paper industry, soda pulping was applied. In chemical compositional analysis, extractive contents of corn stalk (45.1%) was higher than hardwood. With corn stalk pith, soda pulp yield was 25.3% at 10.6 Kappa number, but 39.5% yield with 14.8 Kappa number for corn stalk rind. Higher extractives content in pith is one of the reason for lower pulp yield than rind. Pith pulp fibers had higher fines content than rind pulp. Pith parenchyma cell was removed as fines during pulping or washing process, which caused the lower yield. To use the corn stalks as a raw material for paper making, de-pith process is essential for higher pulp yield and longer pulp length.

• 반도체디스플레이기술학회지
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• 제17권3호
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• pp.31-35
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• 2018

Tungsten disulfide($WS_2$) thin films were directly deposited by direct-current(DC) sputtering and annealed by rapid thermal processing(RTP) to materialize two-dimensional p-type transition metal dichalcogenide (TMDC) thin films on soda-lime glass substrates without any complicated exfoliation/transfer process. $WS_2$ thin films deposited at various DC sputtering powers from 80 W to 160W were annealed at different temperatures from $400^{\circ}C$ to $550^{\circ}C$ considering the melting temperature of soda-lime glass. The optical microscope results showed the stable surface morphologies of the $WS_2$ thin films without any defects. The X-ray photoelectron spectroscopy (XPS) results and the Hall measurement results showed stable binding energies of W and S and high carrier mobilities of $WS_2$ thin films.