• Journal of Powder Materials
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• v.25 no.6
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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.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.6
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• pp.503-506
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• 2004

To clarify the efficient application method of sulfur in safflower, we investigated the growth and seed yield as affected by ammonium sulfate (AS) and sulfur powder. AS was applied to the soil with four levels of 0, 4, 8, and 12 kg/10a and was applied by foliar application with 2 kg/10a as sulfur content compared with sulfur powder 20 kg/10a. By the application of sulfur fertilizer, plant height, stem diameter, and weight of stem and leaves tended to be greater than control. AS was more efficient than sulfur powder in growth of safflower. Sulfur application showed positive effect on yield components and seed yield was increased by $4-10\%$ compared to control. In application effects, AS and foliar application were more efficient than sulfur powder and soil application, respectively.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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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

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.05a
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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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• v.22 no.8
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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.

• Korean Journal of Medicinal Crop Science
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• v.12 no.6
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• pp.454-458
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• 2004

This study was carried out to clarify the effect of sulfur fertilization method on the qualities of safflower (Carthamus tinctorious L.) seed. Sulfur application increased the nitrogen and sulfur content of seed. In nitrogen content, there was no significant difference among sulfur fertilizers, whereas sulfur content was increased by raising ammonium sulfate (AS) amounts by soil application. In application method of AS, there was no significantly difference between foliar application and soil application with 8 kg S/10a. N/S ratio in seed was decreased by sulfur application, and also decreased with the increase of AS amounts by soil application. The contents of lipid and protein were increased by sulfur application. Lipid content was highest in foliar application, and protein content was lowest in AS 4 kg S/10a. By sulfur application, the content of total phenolics and electron donating ability (EDA) were increased by $3.1{\sim}4.7%$ and $3.6{\sim}8.5%$, respectively compared with control. In content of total phenolics, there was no significant difference among sulfur fertilizers, but EDA was higher in sulfur powder 20 kg/10a and AS 8 kg S/10a than that in other fertilizers. Sulfur application showed positive effects on the qualities of safflower seed. In application effects, AS and foliar application were more efficient than sulfur powder and soil application, respectively.

• 한국전기화학회:학술대회논문집
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• 2004.04a
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• pp.13-13
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• 2004

• Journal of the Korean Society of Environmental Restoration Technology
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• v.17 no.1
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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.

• Journal of the Korean Society of Safety
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• v.1 no.1
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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)

• Korean Journal of Medicinal Crop Science
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• v.8 no.4
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• pp.378-385
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• 2000

This study was conducted to investigate the sulfur effects on the yield of safflower (Carthamus tinctorius L.) and the chemical properties of soil after sulfur treatment. Sulfur application was conducted with two chemical forms of sulfur powder and potassium sulfate. Sulfur powder was applied to the soil with levels of 0, 10, 20, 40 kg/10a and potassium sulfate was applied to the soil with levels of 10, 20 kg/10a as sulfur content. After sulfur application in soils, pH and available $P_2O_5$ content of soils tend to decrease after experiment, whereas the contents of $SO_4^{2-}$ and active Fe increased in soils. By the application of sulfur, the yields of safflower seed were increased by about $6{\sim}17$ percent compared to the control. It is apparent that seed yield and plant growth of safflower were increased by the sulfur application.