• 한국분말재료학회지
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• 제25권6호
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• pp.466-474
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• 2018

The high theoretical energy density ($2600Wh\;kg^{-1}$) of Lithium-sulfur batteries and the high theoretical capacity of elemental sulfur ($1672mAh\;g^{-1}$) attract significant research attention. However, the poor electrical conductivity of sulfur and the polysulfide shuttle effect are chronic problems resulting in low sulfur utilization and poor cycling stability. In this study, we address these problems by coating a polyethylene separator with a layer of activated carbon powder. A lithium-sulfur cell containing the activated carbon powder-coated separator exhibits an initial specific discharge capacity of $1400mAh\;g^{-1}$ at 0.1 C, and retains 63% of the initial capacity after 100 cycles at 0.2 C, whereas the equivalent cell with a bare separator exhibits a $1200mAh\;g^{-1}$ initial specific discharge capacity, and 50% capacity retention under the same conditions. The activated carbon powder-coated separator also enhances the rate capability. These results indicate that the microstructure of the activated carbon powder layer provides space for the sulfur redox reaction and facilitates fast electron transport. Concurrently, the activated carbon powder layer traps and reutilizes any polysulfides dissolved in the electrolyte. The approach presented here provides insights for overcoming the problems associated with lithium-sulfur batteries and promoting their practical use.

• 한국작물학회지
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• 제49권6호
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• pp.503-506
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• 2004

홍화 재배시 비효면에서 효과적인 황 시용방법을 구명하고자 황분말 20 kg/10a와 유안의 시용방법 및 시용량을 달리하여 생육 및 수량에 미치는 영향을 비교 조사한 결과는 다음과 같다. 1. 황 유형 및 시용 정도에 따른 생육은 황 시용시 무시용에 비하여 초장이 큰 경향이었으며, 경태와 경엽중이 굵거나 무거웠고, 황 유형간에는 황분말 보다는 유안 처리시 양호한 경향이었다. 2. 황을 시용함으로써 화두수 등 수량구성요소가 전반적으로 증가하는 경향을 보였고, 종실 수량이 $4-10\%$ 증수되었다. 황 유형간에는 황분말보다는 유안이 효과적이었으며, 유안 시비방법 간에는 엽면시비 8.3kg/10a과 토양시비 $33.0\~49.5kg/10a$ 시용구와 차이가 미미하였다.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.1216-1217
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• 2006

We investigated on the additive effect of carbon nanotube in the sulfur electrode on the first discharge curve and cycling property of lithium/sulfur cell. The sulfur electrode with carbon nanotube had two discharge plateau potentials and the first discharge capacity about 1200 mAh/g sulfur. The addition carbon nanotube into the sulfur electrode did not affect the first discharge behavior, but improved the cycling property of lithium/sulfur cell. The optimum content of carbon nanotube was 6 wt% of sulfur electrode

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2015년도 춘계 학술논문 발표대회
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• pp.156-157
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• 2015

Recently, the trend for structure is being changed from wall construction to rhamen construction. rhgamen construction reduces floor noise and selfweight in structures. The amount of lightweight panels used in rhamen construction is also increasing. Also, Worldwide refinery industry is a large amount of sulfur is produced by develrop ment. Sulfur is resistant to freezing and thawing. Terefore, this study focuses on the density and absorption of magnesium oxide matrix that contains wood powder and pearlite to replace lightweight panel for rhamen construction. Adding pearlite 15% has the lowest density but, it has the highest absorption.

• Journal of Microbiology and Biotechnology
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• 제22권8호
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• pp.1155-1160
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• 2012

Sulfur-utilizing autotrophic denitrification relies on an inorganic carbon source to reduce the nitrate by producing sulfuric acid as an end product and can be used for the treatment of wastewaters containing high levels of nitrates. In this study, sulfur-denitrifying bacteria were used in anoxic batch tests with sulfur as the electron donor and nitrate as the electron acceptor. Various medium components were tested under different conditions. Sulfur denitrification can drop the medium pH by producing acid, thus stopping the process half way. To control this mechanism, a 2:1 ratio of sulfur to oyster shell powder was used. Oyster shell powder addition to a sulfur-denitrifying reactor completely removed the nitrate. Using 50, 100, and 200 g of sulfur particles, reaction rate constants of 5.33, 6.29, and $7.96mg^{1/2}/l^{1/2}{\cdot}h$ were obtained, respectively; and using 200 g of sulfur particles showed the highest nitrate removal rates. For different sulfur particle sizes ranging from small (0.85-2.0 mm), medium (2.0-4.0 mm), and large (4.0-4.75 mm), reaction rate constants of 31.56, 10.88, and $6.23mg^{1/2}/l^{1/2}{\cdot}h$ were calculated. The fastest nitrate removal rate was observed for the smallest particle size. Addition of chemical oxygen demand (COD), methanol as the external carbon source, with the autotrophic denitrification in sufficiently alkaline conditions, created a balance between heterotrophic denitrification (which raises the pH) and sulfur-utilizing autotrophic denitrification, which lowers the pH.

• 한국약용작물학회지
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• 제12권6호
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• pp.454-458
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• 2004

잇꽃 종실의 품질 향상에 효과적인 황 시용방법을 구명하고자 황분말 20 kg/10a와 유안의 시용방법 및 시용량을 달리하여 종실의 영양적 품질에 미치는 영향을 비교 조사한 결과는 다음과 같다. 1. 종실의 질소와 황 함량은 황 무시용구에 비해 시용구에서 높은 경향이었다. 황 처리간에는 질소 함량은 차이가 없었으나, 황 함량은 유안 토양시비량이 증가할수록 높아졌다. 유안 시비방법 간에는 토양시비 33 kg/10a와 엽면시비 간에 큰 차이는 없었다. 질소/황 비율은 황 시용으로 질소/황 비율이 저하되었고, 유안 토양시비 간에는 시용량이 증가할수록 감소하여 유안 49.5 kg/10a 처리시 가장 낮았다. 2. 종실의 조지방과 조단백질 함량은 황 시용시 무시용에 비하여 높았으며, 황 유형 간에는 조지방이 유안 엽면시비에서 가장 높았고, 조단백질이 유안 16.5 kg/10a에서 가장 낮았던 것을 제외하고 차이가 없었다. 3. 총페놀성 화합물 함량과 항산화 활성은 황 시용으로 증가하였다. 황 처리 간에는 총페놀성 화합물 함량은 차이가 없었으나, 항산화 활성은 황분말과 유안 33.0 kg/10a 처리에서 다소 높았다.

• 한국전기화학회:학술대회논문집
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• 한국전기화학회 2004년도 춘계총회 및 학술발표회
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• pp.13-13
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• 2004

• 한국환경복원기술학회지
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• 제17권1호
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• pp.1-12
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• 2014

This study was carried out not only to identify the optimum concentrations of sulfur powder and citric acid treated for improving arsenic absorption of Pteris multifuda known as hyperaccumulator of arsenic, but also to develop arsenic purification model in the forest soil. After applying sulfur powder (0, 30, 45, $60g{\cdot}m^{-2}$) and citric acid (0, 200, 400, $800g{\cdot}m^{-2}$) in the forest soil contaminated with heavy metals, P. multifuda was planted and cultivated for 16 weeks. And then the growth and arsenic contents of plants were analyzed. In the result of research, the growth of P. mulifuda, except plant width, cultivated in soils treated with sulfur powder and citric acid was relatively lower than control. The accumulated amount of arsenic in aerial parts of P. multifuda ($1822.2mg{\cdot}kg^{-1}$) cultivated in soils treated with $200g{\cdot}m^{-2}$ citric acid was improved 62.5% against the control. And the accumulated amount of arsenic per 1 $m^2$ ($20.1mg{\cdot}m^{-2}$) was the greatest in $200g{\cdot}m^{-2}$ citric acid treatment. Translocation rate (TR) was higher in all acid treatment compare to control, and was the best in $200g{\cdot}m^{-2}$ citric acid treatment (0.95) especially. It showed that the arsenic absorbed in underground parts was transferred fast to aerial parts. Therefore, $200g{\cdot}m^{-2}$ citric acid treatment in the soil is recommended for arsenic purification using P. multifuda.

• 한국안전학회지
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• 제1권1호
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• pp.27-32
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• 1986

To remove sulfur dioxide from flue gas by the method of metal oxide, copper powder of average diameter $2.4\mu\textrm{m}$and $51\mu\textrm{m}$ were used in a fixed bed reactor over a, temperature range of $300^{\circ}C-500^{\circ}C$. Copper oxide reacts with sulfur dioxide producing cupric sulfate and it can be regenerated from the latter by using hydrogen or methane. Experimental results showed that the reaction rate was increased by the increase of reaction temperature in the range of $300^{\circ}C-422^{\circ}C$ and the removal efficiency of sulfur dioxide was high in case of small size copper particle. However the removal efficiency was decreased at higher temperature due to decomposition of cupric sulfate. The rate controlling step of this reaction was chemical reaction and deactivating catalysts model can be applied to this reaction. The rate constants for this reaction and deactivation are as follows ： k＝8,367exp(-10,298/RT) Kd＝2.23exp(-8,485/RT)

• 한국약용작물학회지
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• 제8권4호
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• pp.378-385
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• 2000

유황시용(硫黃施用)에 따른 토양(土壤) 및 홍화(紅花)의 수량(收量)에 미치는 영향(影響)을 조사(調査)하기 위하여 유황시용량(硫黃施用量)에 따른 토양화학성(土壤化學性) 및 홍화종실(紅花種實)의 수량(收量)을 조사(調査)한 결과(結果)는 다음과 같다. 유황시용후(硫黃施用後) 홍화종실(紅花種實)의 수확기(收穫期)에 토양(土壤)을 분석(分析)한 결과(結果) 토양(土壤)의 pH와 유효인산(有效燐酸)의 함량(含量)이 감소(減少)되었다. 유황처리후(硫黃處理後) 시간(時間)이 경과(經過)함에 따라 유황(硫黃) 처리량(處理量)이 많을수록 활성철함량(活性鐵含量)과 $SO_4^{2-}$ 함량(含量)이 증가(增加)하였다. 유황시용량(硫黃施用量)이 증가함에 따라 건물중(乾物重)이 증가하였으며, 홍화종실수량(紅花種實收量)은 증가(增加) 하는 경향(傾向)이었으며 유황(硫黃) 20 kg/10a시용구(施用區)에서 가장 높았다. 따라서, 홍화재배지(紅花栽培地)의 유황처리(硫黃處理)는 수량(收量) 및 품질(品質)에 효과적(效果的)인 것으로 나타났으며, 수량구성요소(收量構成要素) 측면(側面)에서 20 kg/10a 처리(處理)가 효과적(效果的)인 것으로 판단(判斷)되었다.