• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.1
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• pp.42-49
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• 2008

GDD models of corn were developed in bare soil, while sweet and super sweet corns are grown under black polyethylene (P. E.) film mulch in Korea. To develop a suitable GDD model under black P. E. film mulch, a super sweet com hybrid "Cambella-90" was planted from 1 April to 30 June in 2003 at the 10-day intervals under black P. E. film mulch and in bare soil. In bare soil the best GDD model was $GDD\;=\;{\sum}[H"+L')/2\;-\;10^{\circ}C]$, where H" was daily maximum temperature but is was substituted for $30^{\circ}C$ - (daily maximum temperature - $30^{\circ}C$) when higher than $30^{\circ}C$ and L' was daily minimum temperature, but it was substituted for $10^{\circ}C$ when lower than $10^{\circ}C$. The same GDD model could be adapted for com grown under black P. E. film mulch, but base temperature was substituted for $9^{\circ}C$. To determine planting date for the scheduled harvests, accumulated GDDs were calculated using 30-year average temperature data during the growing season. Under black P. E. film mulch planting dates were determined by subtracting GDD of the hybrid, $970^{\circ}C$, from accumulated GDD of scheduled harvest dates.

• Applied Chemistry for Engineering
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• v.16 no.5
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• pp.689-692
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• 2005

In order to improve the electrochemical performances of Li-ion batteries when spinel $LiMn_2O_4$ is employed as a cathode active material, binary conductive agents were prepared using two different particle-sized carbons like Super P Black and $Vulcan^{(R)}$ XC-72R. The electrochemical performances of the $LiMn_2O_4$ cell system using binary conductive agents were evaluated in terms of specific charge and discharge capacities and cycle life. The cell with binary conductive agent in the 3:7 weight ratios of Super P Black and $Vulcan^{(R)}$ XC-72R showed better electrochemical performances due to the proper combination of ionic diffusion rate and electric contact.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.3
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• pp.325-333
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• 2007

To find out the planting times for the economic yield of a super sweet corn hybrid, "Cambella 90" was planted from 1 April of 2003 and 2004 at the 10 days intervals under black polyethylene (P. E.) film mulch and in bare soil in Gyeongsan. Daily maximum soil temperature under black P. E. film mulch was lower, while daily minimum soil temperature was higher compared to bare soil. Soil moisture content under black P. E. film mulch maintained optimum level longer than in bare soil. Emergence rate, percent stand, culm length, and the number of marketable ears were higher under black P E. film mulch compared to bare soil. Silking date under black P. E. film mulch was earlier compared to bare soil by $4{\sim}6$ days at April plantings, while only 1 day earlier at June plantings. Silking date of individual plants in a plot ranged $3{\sim}5$ days depending on planting dates and soil mulch in the same plot. The number of large ears decreased as planting dates delayed. Considering emergence rate and the number of marketable ears, the planting time for the economic yield of a super sweet com hybrid, "Cambella 90" ranged 1 April to 20 June in the southern part of Korea.

• Journal of the Korean Applied Science and Technology
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• v.25 no.3
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• pp.363-369
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• 2008

In the present work, the choice of the nano carbon black and optimum mixed ratio and effectiveness of the mixed carbon black to get a raw data for a manufacturing method of conductive complex board. Optimum mixed ratio of paper sludge & water was 1 : 2.5 for reformations. HB-41-Y was cheaper than Super-P with the single carbon black. Also electric conductivity of HB-41-Y($6.406{\times}10^{-2}\;{\Omega}cm^{-1}$) was about 6.5 times higher than Super-P($9.741{\times}10^{-3}\;{\Omega}cm^{-1}$) at 20 wt% carbon black. This time optimum mixture ratio of the paper sludge and the carbon black to be about 15 wt%, optimum mixed ratio HB-41Y and Graphite about 3:1 and its electric conductivity was $5.824{\times}10^{-2}\;{\Omega}cm^{-1}$.

• Journal of the Korean Applied Science and Technology
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• v.32 no.3
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• pp.405-411
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• 2015

Carbon composites for flexible fiber heating element were examined to improve the electrical conductivity in this study. Carbon composites using carbon black, denka black, super-c, super-p with/without CNF or dispersant such as BCS03 and Sikament-nn were prepared. Carbon composite slurry was coated on plane film and yarns(cotton, polyester) and the performances of prepared heating materials were investigated by checking electrical surface resistance, adhesion strength. The plane heating element using carbon black under natural drying condition($25^{\circ}C$) had better physical properties such as surface resistance(185.3 Ohm/sq) and adhesion strength(above 90%) than those of other carbon composite heating elements. From these results, polyester heating element coated by carbon black showed better electrical line resistance(33.2 kOhm/cm) than cotton heating element. Then, it was found that polyester heating element coated by carbon black with CNF(3 wt%) and BCS03(1 wt%) appeared best properties(0.604 kOhm/cm).

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.8
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• pp.702-707
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• 2005

Spinel $LiMn_2O_4$ has become appealing because manganese is inexpensive and environmentally benign. In general, cathodes for lithium ion batteries include carbon as a conductive agent that provides electron transfer between the active material and the current collector. In this work, we selected Acetylene Black and Super P Black as conductive agents, and then carried out their comparative investigation for the performances of the $Li/LiMn_2O_4$ cells using different conductive agents with different particle size. In addition, their electrochemical impedance characteristic of $Li/Mn_2O_4$ cells using different conductive agents is effectively identified through a.c. impedance technique. As a consequence, $Li/LiMn_2O_4$ cells with Super P Black show better electrochemical performances ascribed to the significant contribution of feasible ionic conduction due to larger particle size than those with Acetylene Black.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.593-594
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• 2005

Lithium-ion batteries have used the layered $LiCoO_2$ materials as cathodes, but Co is relatively toxic and expensive. In this regard, the spinel $LiMn_2O_4$ has become appealing because manganese is inexpensive and environmentally benign. In general, cathodes for lithium ion batteries include carbon as a conductive agent that provides electron transfer between the active material and the current collector. In this work, we selected Acetylene Black and Super P Black as conducting agents, and then carried out comparative investigation for the performances of the cells using different conducting agents with different particle size. As a consequence, Li/$LiMn_2O_4$ cells with Super P Black show better electrochemical performances than those with Acetylene Black.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.9
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• pp.973-978
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• 2004

This work describes the effect of conducting materials on the electrochemical performances of electric double layer capacitor. Three kinds of Carbon black, such as Acethylene Black, Super P Black, Ketjen black supplied by Denki Kagaku Kogyo, MMM Carbon, Ketjen Black International Co. respectively, was added in carbon-Polytetrafluoroethylene (PTFE) electrode, which composition is activated carbon : carbon black : PTFE = 80 : 15 : 5 wt.%, and were compared with their electrochemical properties. The electrode with Ketjen Black has showed the lowest resistance than other carbon black, and also exhibited the better rate capability between 0.5 mA/cm$^2$ ∼ 100 mA/cm$^2$ current density in unit cell capacitor. On the other hand, as increasing the composition of Ketjen Black, the specific resistances of electrodes were decreased and Ketjen Black content higher than 15 wt% increased. The best rate capability was obtained at the electrode with 15 wt.% of Ketjen Black in unit cell capacitor. This behaviors would be correlated with the dense structure of electrode.

• Carbon letters
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• v.12 no.4
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• pp.243-248
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• 2011

Two different types of graphite, such as flake graphite (FG) and spherical graphite (SG), were used as anode materials for a lithium-ion secondary battery in order to investigate their electrochemical performance. The FG particles were prepared by pulverizing natural graphite with a planetary mill. The SG particles were treated by immersing them in acid solutions or mixing them with various carbon additives. With a longer milling time, the particle size of the FG decreased. Since smaller particles allow more exposure of the edge planes toward the electrolyte, it could be possible for the FG anodes with longer milling time to deliver high reversible capacity; however, their initial efficiency was found to have decreased. The initial efficiency of SG anodes with acid treatments was about 90%, showing an over 20% higher value than that of FG anodes. With acid treatment, the discharge rate capability and the initial efficiency improved slightly. The electrochemical properties of the SG anodes improved slightly with carbon additives such as acetylene black (AB), Super P, Ketjen black, and carbon nanotubes. Furthermore, the cyclability was much improved due to the effect of the conductive bridge made by carbon additives such as AB and Super P.

• Journal of Bio-Environment Control
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• v.22 no.2
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• pp.81-86
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• 2013

This experiment was carried out to select white asparagus varieties suitable for shading culture in greenhouse. Eight white and one green varieties were tested. Seeds were sown in 72-cell trays in a glasshouse on 24 Dec. 2008 and the seedlings were transplanted in a P.E house on 22 May 2009. Planting distances were 30 cm apart in a raw and 125 cm between the raws. For white asparagus production, small tunnel ($210cm{\times}160cm$) was established inside the P.E house, and covered with black and white P.E film (0.1 mm) on 5 March 2010. Days to sprouting took 5 days in 'Ravel' variety and took 16 to 18 days in 'Backlim', 'Horlim', 'Herkolim' varieties. The number of spear was highest in 'Ravel' with 6 and lowest in 'Backlim' with 3.7. The spear weight was heaviest in 'Herkolim' with 25.6 g and lightest in 'Ravel' with 15.6 g. The highest total yield was in 'Herkolim' with 296 kg/10a, followed by 'Super welcome' with 275 kg/10a and lowest in 'Rapsody' with 176 kg/10a. Marketable yields in 'Super welcome' and 'Herkolim' were 241 kg/10a and 239 kg/10a, respectively, and the yield was lowest in 'Rapsody' with 139 kg/10a. The L grade (over 20 g of spear weight) was highest in 'Herkolim'. Accordingly, 'Herkolim' was the most suitable white asparagus variety among the tested varieties for shading cultivation in greenhouse.