• Journal of the Korean Chemical Society
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• v.7 no.1
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• pp.65-68
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• 1963

The solubility of ethyl bromide in nitrobenzene and in 1,2,4-trichlorobenzene has been measured at $19^{\circ}$ in the presence and absence of gallium bromide. When gallium bromide does not exist in the system, the solubility of ethyl bromide in nitrobenzene is greater than in 1,2,4-trichlorobenzene, indicating the stronger interaction of ethyl bromide with nitrobenzene than with 1,2,4-trichlorobenzene. When there exists gallium bromide in the system, an unstable 1: 1 complex, C2H5Br·GaBr3, of gallium bromide with ethyl bromide is formed in the solution. The 1: 1 complex in solution dissociates into the components to a large extent according to one of the following equilibria or both: $C_2H_5Br{\cdot}GaBr_3{\rightleftarrows}C_2H_5Br+GaBr_3$C_2H_5Br{\cdot}GaBr_3{\rightleftarrows}C_2H_5Br+1}2GaBr_3$$ The stability of the 1: 1 complex of ethyl bromide with gallium bromide is compared with that of the corresponding complex of methyl bromide.

• Journal of the Korean Chemical Society
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• v.38 no.3
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• pp.208-213
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• 1994

The solubility of i-butyl bromide in nitrobenzene have been measured at 19, 25 and $40^{\circ}C$ in the presence and absence of gallium bromide. In the presence of gallium bromide, 1 : 1 complex, $i-C_4H_9Br{\cdot}GaBr_3$ is formed in the solution. The instability constant K of the complex formation was evaluated from the following equilibrium equation. $i-C_4H_9Br{\cdot}GaBr_3{\rightleftharpoons}C_4H_9Br + 1/2Ga_2Br_6.$ From these result, it seems that the stabilities of the complex formation, gallium bromide with alkyl bromide, are directly related with those of the carbonium ions of alkyl bromide.

• Journal of the Korean Chemical Society
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• v.6 no.1
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• pp.77-83
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• 1962

The solubilities of hydrogen bromide and methyl bromide in nitrobenzene and in 1,2,4-trichlorobenzene have been measured in the presence and absence of gallium bromide. When gallium bromide does not exist in the system, the solubilities of HBr and MeBr in nitrobenzene are greater than in 1,2,4-trichlorobenzene, indicating the greater basicity of nitrobenzene than 1,2,4-trichlorobenzene. When there exists gallium bromide in the system, the addition compounds, GaBr3·HBr and GaBr3·CH3Br, have been found to exist in solution. The addition compound of GaBr3·HBr is stable in nitrobenzene but unstable in 1,2,4-trichlorobenzene. On the other hand the addition compound of $GaBr_3{\cdot}CH_3Br$ is unstable in both solvents. All of these unstable addition compounds dissociate into components to large extents according to one of the following equilibria or both: $$GaBr_3{\cdot}RBr{\leftrightarrows}GaBr_3+RBr\;GaBr_3{\cdot}RBr{\leftrightarrows}1}2\;Ga_2Br_6+RBr$.$ where R denotes either hydrogen atom or methyl group.

• Journal of the Korean Chemical Society
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• v.24 no.4
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• pp.302-309
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• 1980

The solubilities of n-propyl bromide in nitrobenzene and in 1,2,4-trichlorobenzene have been measured at 19, 25 and $40^{\circ}C$ in the presence and absence of gallium bromide. When gallium bromide does not exist in the system, the solubility of n-propyl bromide in nitrobenzene is greater than in 1,2,4-trichlorobenzene, indicating a stronger interaction of n-propyl bromide with nitrobenzene than with 1,2,4-trichlorobenzene. In the presence of gallium bromide, 1: 1 complex $n-C_3H_7Br\cdotGaBr_3$ is formed in the solution. The instability constant K of the complex was evaluated. $$n-C_3H_7Br\cdotGaBr_3 \rightleftarrows n-C_3H_7Br ＋ \frac{1}{2Ga_2Br_6 }$$The change of enthalpy, free energy and entropy for the dissociation of the complex were also calculated. It seems that the stabilities of the complex, gallium bromide with alkyl bromide, are relatively concerned with the stabilities of the alkyl ion.

• Journal of the Korean Chemical Society
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• v.15 no.5
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• pp.228-235
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• 1971

The solubilities of n-butyl bromide in nitrobenzene and in 1,2,4-trichlorobenzene have been measured at $19^{\circ},\;25^{\circ},\;and\;40^{\circ}C$ in the presence and absence of gallium bromide. When gallium bromide does not exist in the system, the solubility of n-butyl bromide in nitrobenzene is greater than in 1,2,4-trichlorobenzene, indicating a stronger interaction of n-butyl bromide with nitrobenzene than with 1,2,4-trichlorobenzene. In the presence of gallium bromide, complex of n-butyl bromide with gallium bromide, 1:1 complex, $n-C_4H_9Br{\cdot}GaBr_3$, is formed in the solution. The instability constant K of the complex was evaluated. $n-C_4H_9Br{\cdot}GaBr_3{\rightleftharpoons}n-C_4H_9Br+\frac{1}{2}Ga_2Br_6$ The changes of enthalpy, free energy and entropy for the dissociation of the complex were also calculated.

• Journal of the Korean Chemical Society
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• v.29 no.1
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• pp.9-14
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• 1985

The solubilities of i-propyl bromide in nitrobenzene have been measured at 10$^{\circ}$, 19$^{\circ}$ and 25$^{\circ}C$ in the presence and absence of gallium bromide. In the presence of gallium bromide, 1 : 1 complex, i-C$_3$H$_7Br{\cdot}GaBr_3$ is formed in the solution. The instability constant K of the complex formation was evaluated from the following equilibrium equation: i-C$_3$H$_7Br{\cdot}GaBr_3$ ${\rightleftharpoons}$ i-C$_3$H$_7$Br + $\frac{1}{2}$$Ga_2Br_6$. The change of enthalpy, free energy and entropy for the dissociation of the complex were also calculated. From these result, it seems that the stabilities of the complex formation, gallium bromide with alkyl bromide, are directly related with those of the carbonium ions of alkyl bromide.

• Journal of the Korean Chemical Society
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• v.35 no.5
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• pp.480-486
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• 1991

The solubilities of ethyl bromide in aniline and o-chloroaniline have been measured at 5, 15$^{\circ}$ and 25$^{\circ}$C in the presence and the absence of gallium bromide. When gallium bromide does not exist in the system, the solubility of ethyl bromide in o-chloroaniline is greater than in aniline, indicating a stronger interaction of ethyl bromide with o-chloroaniline than that with aniline. It could be thought that ethyl bromide forms unstable complex with gallium bromide in the presence of gallium bromide in the system. This complex has been assumed in various ways and evaluated, that instability constant (K value) is relatively constancy under the assumption of 1 : 1 complex, $C_2H_5Br{\cdot}GaBr_3$. Therefore, the complex forms the following equilibrium in the solution: $C_2H_5Br{\cdot}GaBr_3\;{\rightleftharpoons}\;C_2H_5Br +1/2Ga_2Br_6$ The instability of the complex of ethyl bromide with gallium bromide is compared with similar complexes of gallium bromide with methyl bromide. The changes of enthalpy, free energy and entropy fcor the dissociation of the complex are also calculated.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.3
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• pp.444-449
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• 2001

Comparative effects of gamma irradiation and methyl bromide (MeBr) fumigation on disinfestation and physicochemical attributes of mung bean were investigated. Insects in domestic mung bean were identified to be Collosobruchus chinensis Linne. Ina disinfestation test, MeBr showed 100% disinfestation effect on Larva and adult at 5th day after treatments, while irradiation dose above 3 kGy was effective for disinfesting all larva at that time. Adults were more sensitive to radiation than larva. Around 1 kGy was enough to control larva and adult in mung bean following 10 to 15 days of irradiation. In physicochemical properties of treated sampels, nitrogen solubility, TBA value, amino acid and fatty acid compositions were not different among the control, 2.5 kGy-irradiated and MeBr-fumigated samples. MeBr fumigation caused the decrease in lightness (Hunter's L value) and the increase in redness (a value) and yellowness (b value), thereby resulting in overall color difference (${\Delta}E$) in a noticeable level (NBS 2.61~2.94).

• Journal of the Korean Chemical Society
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• v.8 no.2
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• pp.39-42
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• 1964

As the bromination method with $Br_2^{82}$ for the synthesis of 5-bromouracil-$Br^{82}$ gave products with considerable impurities, e. g. uracil etc. an attempt to produce pure one by isotopic exchange method was performed. Bromide-82 ion such as $NH_4Br^{82}$ or $HBr^{82}$ undergoes no isotopic exchange with 5-bromouracil-Br. However, isotopic exchange between $NH_4Br^{82}$ and $Br_2$, and between $Br_2^{82}$ and 5-bromouracil-Br were too fast to determine the rate. The result indicated that this method can be used in the production of pure 5-bromouracil-$Br^{82}$. It was also found that the use of reducing agent to maintain $Br^{82}$ as bromide form was unnecessary on $NH_4Br^{82}$ production from reactor.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1996.10b
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• pp.190-192
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• 1996

본 연구는 기존의 Water-Lithium Bromide(H2O/LiBr) 용액에 비해 부식성이 낮은 Water-Lithium bromide-Lithium Nitrate계(H2O/LiBr-LiNO3)용액의 용해도, 증기압, 점도, 표면장력 등의 물리적 성질을 조사하였다. 또한 용해도가 가장 큰 최적의 혼합 몰비를 구하여 증기압 및 점도, 표면장력등의 물성을 구함으로써 흡수식 냉온수기용 홉수제 개발의 기본 자료를 확보하였다. 이러한 연구 결과로부터 다성분 Lithium 염 혼합물계로 이루어진 흡수용액 개발의 기초자료로 이용하고자 한다.