• Bulletin of the Korean Chemical Society
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• v.3 no.2
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• pp.55-60
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• 1982

The rate of the bromine-exchange reaction of antimony tribromide with benzyl bromide in nitrobenzene or 1,2,4-trichlorobenzene has been measured, using Br-82 labelled antimony tribromide. The result of the study indicates that the exchange reaction is first order with respect to benzyl bromide, and either second or first order with respect to antimony tribromide depending on its concentrations. The second-order kinetics with respect to antimony tribromide have been observed at relatively high $[SbBr_3]$ concentrations, and the first-order kinetics at lower $[SbBr_3]$ concentrations. Reaction mechanisms are proposed for the exchange reaction.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2017.10a
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• pp.361-362
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• 2017

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.21 no.6
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• pp.274-279
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• 2011

In this study, we investigated the analytical methods for bromine (Br) and chloride (Cl) with oxygen combustion bomb, using a halogen-containing polymer materials. On measuring Cl content, it showed less reproducibility of the results applying Mohr method or potentiometric titration method than those applying acid-base titration method. In both Br and Cl tests with an oxygen combustion bomb, their concentrations in the absorption and cleaning solution with distilled water were much higher than those in the combustion gas. On the other hand, the concentration level of Br measured by the oxygen combustion bomb method were a little bit lower than those measured by XRF or combustionion chromatography.

• Korean Journal of Crystallography
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• v.8 no.2
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• pp.127-131
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• 1997

The crystal structure of a bromine sorption complex of vacuum-dehydrated Ag+ and Ca2+ exchanged zeolite A(a=12,234(1) Å) has been determined by single-crystal X-ray diffraction methods in the cubic space group Pm3m. The crystal was prepared by flow method using exchange solution in which mole ratio of AgNo3 and Ca(NO3)2 was 1:150 with a total concentration of 0.05M. The crystal was dehydrated at 360℃ and 2 ×10-6 Torr for 2days, followed by exposure to 180 Torr of Br2 vapor for 20min. full-matrix least-squares refinements converged to the final error indices of R1=0.111 and R2=0.101 using 90 reflections for which I>3o(I). About 3.1 Ag+ ions and 4.45 Ca2+ ions lie on the two crystallographically nonequivalent three-fold axes associated with 6-ring oxygens. A total of six bromine molecules are sorbed per unit cell. Each bromine molecule approaches a framework oxide ions axially (Br-Br-O=171(2)', O-Br=3.25(6) Å; and Br-Br=2,61(8) Å by a charge-transfer interaction.

• Proceedings of the Korean Fiber Society Conference
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• 1991.06a
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• pp.20-21
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• 1991

• Proceedings of the Optical Society of Korea Conference
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• 2006.07a
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• pp.125-126
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• 2006

• Bulletin of the Korean Chemical Society
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• v.15 no.8
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• pp.607-608
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• 1994

• Archives of Pharmacal Research
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• v.6 no.1
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• pp.1-6
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• 1983

The reaction of ethylenecarbonate (I) with bromine was carried out in the presence of benzolperoxide as radical initiator. The following several different esters being ring opened were obtained; bromoacetyl-bromoformate, (1-hyroxy, 1, 2-dibromo)-ethyl bromoformate, (1-hydroxy, 1, 2, 2'-tribromo)diethylacarbonate, 2-bromoethyl-tribromoacetate, (1-acetoxy, 1'-bromomethyl)-bromomalo nate, 2-bromoethyl-bromoacetoxy-tribromoacetate.

• Bulletin of the Korean Chemical Society
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• v.23 no.2
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• pp.189-194
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• 2002

Two-photon resonant third photon ionization of atomic bromine $(4p^5\;^2P_{3/2}\;and\;^2P_{1/2})$ has been studied using a photoelectron imaging spectroscopy in the wavelength region 250 - 278 nm. The technique has yielded simultaneously both relative branching ratios to the three levels of $Br^+(^3P_2,\;^3P_{0.1}\;and^1D_2)$ with $4p^4$ configuration and the angular distributions of outgoing photoelectrons. The product branching ratios reveal a strong propensity to populate particular levels in many cases. Several pathways have been documented for selective formation of $Br^+(^3P_2)$ and $Br^+(^3P_{0.1})$ ions. In general, the final ion level distributions are dominated by the preservation of the ion core configuration of a resonant excited state. Some deviations from this simple picture are discussed in terms of the configuration interaction of resonant states and the autoionization in the continuum. The photoelectron angular distributions are qualitatively similar for all transitions, with a positive $A_2$ anisotropy coefficient of 1.0-2.0 and negligible $A_4$ in most cases, which suggests that the angular distribution is mainly determined by the single-photon ionization process of a resonant excited state induced from the third photon absorption.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.33 no.1 s.60
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• pp.11-15
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• 2007

Oxidation/reduction titrations are important quantitative procedures for many chemicals. Several widely used analytical methods for cosmetic ingredients are based on the redox reactions. In this article, we summarized basic theories of redox titration and applications. Determination of unsaturation properties based on iodine or bromine number, quantitation of hydrogen peroxide or peroxide materials in several cosmetic ingredients and measurement of titanium dioxide, widely used sunscreen agent, in cosmetics are discussed here.