• Polymer(Korea)
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• v.33 no.5
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• pp.509-513
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• 2009

For examining an effect of lithium bromide on structure and property of chitosan/fibroin blend, we investigated the structural characteristic of chitosan/fibroin blend films using solution with lithium bromide which was removed during a casting. The chitosan/fibroin blend formed a complex with the dissolved bromine/lithium ions. The crystalline phase of the complex was found in the blend film at LiBr concentration of 0.6 mol/L. The degree of crystallization was decreased with increasing the concentration of LiBr. The hydrated crystalline phase of chitosan was formed in the blend film that lithium bromide was removed in the process of casting by neutralization and osmotic action. The crystallinity of this film was increased largely as compared with that of the film without lithium bromide. The complexed blend film formed hydrogel absorbing plenty of water.

• Journal of the Korean Chemical Society
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• v.27 no.1
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• pp.46-52
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• 1983

Selective reduction of halide (Br, I) with lithium borohydride in halogen compounds containing chloro, nitro, ester and nitrile groups was achieved satisfactorily. 1-Bromo-4-chlorobutane was reduced to 1-chlorobutane in 96% yield and the reduction of p-nitrobenzyl bromide gave p-nitrotoluene in 98% yield. However, the selectivity on the reduction of ethyl 3-iodopropionate and 4-bromobutyronitrile required the presence of equimolar pyridine to give good yield of ethyl propionate (93%) and n-butyronitrile (88%), respectively. In competitive reduction of 1-bromoheptane and 2-bromoheptane, lithium borohydride reduced 1-bromoheptane preferentially in the molar ratio of 93:7.

• Journal of the Korean Electrochemical Society
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• v.18 no.2
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• pp.51-57
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• 2015

We report the effect of the impurities including water and bromide in the propylmethylpyrrolidinium bis(trifluoromethanesulfonyl)imide (PMPyr-TFSI) on the electrochemical performance of lithium ion batteries. The several kinds of PMPyr-TFSI electrolytes with different amount of impurities are applied as the electrolyte to the cell with the high potential electrode, $LiNi_{0.5}Mn_{1.5}O_4$ spinel. It is found that the impurities in the electrolytes cause the detrimental effect on the cell performance by tracing the cycleability, voltage profile and Coulombic efficiency. Especially, the polarization and Coulombic efficiency go to worse by both impurities of water and bromide, but the cycleability was not highly influenced by bromide impurity unlike the water impurity.