• Food Science and Preservation
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• v.10 no.3
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• pp.381-387
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• 2003

‘Fuji’ apples were treated by gamma irradiation (0 - 3 kGy) or methyl bromide fumigation at commercial conditions (MeBr, 26 g/kg, 4 hr) for quarantine purposes at two different treatment timing after harvest and stored under air at 0$^{\circ}C$ for 4 months. Associated with the treatment timing of irradiation or fumigation, after 40 days of storage at 0$^{\circ}C$ following harvest was more adequate than immediately after harvest in keeping qualities of stored apples. However, more than 2 kGy irradiation and MeBr fumigation were detrimental to physiological and chemical qualities of the fruits. These results show that less than 1 kGy irradiation at the delayed timing has a possibility to be applied as a quarantine procedure without significant changes in the quality of apples.

• Journal of Microbiology and Biotechnology
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• v.14 no.6
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• pp.1256-1266
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• 2004

2-Bromooctanoic acid (2-BrOA) is known to block the formation of polyhydroxyalkanoic acid (PHA) in Pseudomonasfluorescens BM07 without any influence on the cell growth when grown on fructose, but it inhibits the cell growth when grown on octanoate (OA) (Lee et al., Appl. Environ. Microbiol. 67: 4963- 4974, 2001). We investigated the role of 2-BrOA in the PHA synthesis of the bacterium grown with mixtures of fructose and fatty acids. OA, 11­phenoxyundecanoic acid (1 1-POU), and 5-phenylvaleric acid (5-PV) were selected as model substrates. When supplemented with 50 mM fructose, all these carboxylic acids suppressed the formation of PHA from fructose, however, the ~-oxidation coenzyme A monomers derived from the carboxylic acids were efficiently polymerized, but the conversion yield [(mol of carboxylate substrate converted into PHA)/(mol of carboxylate substrate in the feed)] was low (e.g., maximally $\~53\%$ for 5 mM 11-POU). Addition of 2-BrOA (up to 5 mM) to the mixed carbon sources raised the conversion yield sensitively and effectively only at low levels of the acid substrates (e.g., 2 mM 1 1-POU or 5 mM OA): For instance, $100\%$ of 2 mM ll-POU were converted into PHA in the presence of 5 mM 2-BrOA, whereas only $\~10\%$ of the 1 1-POU were converted in the absence of 2-BrOA. However, at highly saturated suppressing levels (e.g., 5 mM ll-POU), 2-BrOA inhibitor showed no significant additional effect on the conversion ($60- 70\%$ conversion irrespective of 2-BrOA level). The existence of competitive and compensative relationship between 2­BrOA and all the carboxylic acid substrates used may indicate 'Present address: Section on Brain Physiology and Metabolism, Bldg. 10, Rm. 6N202, National Institute on Agmg, National Institute of Health, Bethesda, MD 20892, U.S.A. that all the acid substrate-derived inhibiting species bind to the same site as the 2-BrOA inhibiting species does. We, therefore, suggest that 2-BrOA can be used for efficiently increasing the yield of conversion of expensive substituted fatty acids into PHA and then substituted 3-hydroxyacids by hydrolyzing it.

• Proceedings of the KAIS Fall Conference
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• 2004.06a
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• pp.315-318
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• 2004

This study was designed to investigate the cytotoxic effect of Cephaxus koreana on human breast cancer cell lines (SCC-1395 and SK-BR-3) us ins MTT(3- [4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay. RPMII -1640 medium with $10\%$ FBS and $1\%$ of penicillin-streptomycin was used. The ethanol extrart of Cephaxus koreana after adsoption resin treatment showed higher anticancer activity against SCC- 1395 than the ethanol extract of Cephaxus koreana without adsoption resin treatment. SK-BR-3 showed higher sensitivity activity than SCC-1395 at the same concentration of 20000 ppm.

• Journal of the Korean Chemical Society
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• v.21 no.4
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• pp.227-234
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• 1977

The reaction of phenylhydrazine with bromine in sulfuric acid solution has been studied kinetically. The pseudo-second-order rate constant is approximately inversely proportional to hydrogen-ion concentration when the concentration of sulfuric acid is lower than 1M. arom the study of the effect of potassium bromide concentration on the rate constant, it is concluded that both neutral bromine and tribromide ion participate in the reaction, the rate constants in 0.01M $H_2SO_4$ being $5{\times}10^5M^{-1},sec^{-1}\;and\;0. 7{\times}10^5M^{-1},sec^{-1}$, respectively at $20^{\circ}C$. The pseudo-second-order rate constant of 2.4-dinitrophenylhydrazine-bromine reaction is independent of hydrogen ion concentration. From the KBr addition experiment, the rate constants for $Br_2\;and\;Br_3^-$ were obtained as $1.2{\times}10^5M^{-1},sec^{-1}\;and\;2.0{\times}10^4M^{-1},sec^{-1}$, respectively.

• Journal of Korean Ophthalmic Optics Society
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• v.19 no.4
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• pp.505-511
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• 2014

Purpose: This study was to investigate the effect of breath alcohol concentration (BrAC) increase with drinking alcohol on contrast sensitivity in the conditions of restricted BrAC. Methods: 23 males in 20s (average age $21.17{\pm}2.19$ years, body mass index (BMI) $22.09{\pm}2.16$) were selected and administered the amount of alcohol to reach 0.05% and 0.08% BrAC calculated by BAC (blood alcohol concentration) Dosing Software program, which was developed as basis of Watson's formula. Then, the contrast sensitivity in various luminance conditions (photopic, mesopic, and mesopic with glare) was measured and compared between these conditions. Results: The contrast sensitivity in all spatial frequency was decreased with BrAC increase. Although BrAC was increased, the peak of contrast sensitivity didn't change as 6 cycle per degree (cpd) in the photopic condition and 3 cpd in the mesopic condition, respectively. But, in the mesopic condition with glare, the peak of contrast sensitivity was shifted from 6 cpd at 0% and 0.05% BrAC to 3 cpd at 0.08% BrAC with increase of alcohol concentration. Conclusions: The increase of BrAC by drinking alcohol induces the decrease of contrast sensitivity in all spatial frequency and the shift of peak of contrast sensitivity, which can cause safety accidents, and may have an effect on various visual tasks.

• Journal of Environmental Science International
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• v.21 no.4
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• pp.421-435
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• 2012

Novel $N_2O_2$ tetradentate ligands, H-3BPD and H-2BPD were synthesized. Hydrochloric acid salts of Br-3BPD, Cl-3BPD, Br-2BPD and Cl-2BPD having Br and Cl substituents at the $para$ position of the phenol hydroxyl group, were synthesized. The ligands were characterized by C. H. N atomic analysis, $^1H$ NMR, $^{13}C$ NMR, UV-visible, and mass spectra. The proton dissociation constants ($logK_n{^H}$) of the phenol hydroxyl group and secondary amine of the synthesized $N_2O_2$ ligands were shown by four step wise values. The orders of the calculated overall proton dissociation constants ($log{\beta}_p$) were Br-3BPD < Cl-3BPD < H-3BPD in case of 3BPD and Br-2BPD < Cl-2BPD < H-2BPD in case of 2BPD respectively. The order agreed well with that of $para$ Hammett substituent constants(${\delta}_p$). The stability constants($logK_{ML}$) of the complexes between the synthesized ligands and transition metal(II) ions agreed with the order of $log{\beta}_p$ of the ligands. The order of the $logK_{ML}$ value of the each transition metal (II) ion was Co(II) < Ni(II) < Cu(II) > Zn(II) > Cd(II) > Pb(II), which agreed well with that of Iriving-Williams series.

• Journal of the Korean Chemical Society
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• v.11 no.3
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• pp.89-93
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• 1967

The interactions of fluorobenzene with iodine monochloride, iodine monobromide, bromine and chlorine in carbon tetrachloride solution have been examined through ultraviolet spectrophotometric measurements. The results indicate the formation of one to one molecular complexes, $C_6H_5F{\cdot}ICl$, $C_6H_5F{\cdot}IBr$, $C_6H_5F{\cdot}Br_2$, and $C_6H_5F{\cdot}Cl_2$ in solution. The equilibrium constants obtained at room temperature for the formation of these four complexes are 0.161, 0.072, 0.045 and 0.035 l $mole^{-1}$, respectively. Comparison of these results with those reported in the literature on other complexes of similar type reveals that the relative stabilities of these complexes decrease in the following orders: ICl>IBr>$I_2$>$Br_2$>$Cl_2$ $C_6H_6$>$C_6H_5Br$>$C_6H_5Cl$>$C_6H_5F$

• Journal of the Korean Solar Energy Society
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• v.26 no.4
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• pp.73-81
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• 2006

In this paper, with water-LiBr-LiSCN mixture which utilizes solar energy as mid temperature range evaporator heat source, a thermodynamic analysis was performed to provide design data for a double-effect absorption heating system. A comparative study of the water-LiBr-LiSCN mixture against the water-LiBr pair was conducted by a computer simulation. The computer simulation is based on mass, material and heat balance equations for each part of the system. Coefficients of performance and flow ratios for effects of different operating temperatures are investigated. It is found that the heating COP is higher for the water-LiBr-LiSCN mixture than for the water-LiBr pair, and FR is lower for the former.

• Journal of Radiation Protection and Research
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• v.41 no.2
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• pp.167-171
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• 2016

Background: TlBr is of considerable technological importance for radiation detection applications where detecting high-energy photons such as X-rays and ${\gamma}$-rays are of prime importance. However, there were few reports on investigating optical properties of TlBr itself for deeper understandings of this material and for making better radiation detection devices. Thus, in this paper, we report on the optical characterizations of TlBr single crystals. Spectroscopic ellipsometry (SE) and photoluminescence (PL) measurements at RT were performed for this work. Materials and Methods: A 2-inch TlBr single crystalline ingot was grown by using the vertical Bridgman furnace. SE measurements were performed at RT within the photon energy range from 1.1 to 6.5 eV. PL measurements were performed at RT by using a home-made PL system equipped with a 266 nm-laser and a spectrometer. Results and Discussion: Dielectric responses from SE analysis were shown to be slightly different among the different samples possibly due to the different structural/optical properties. Also from the PL measurements, it was observed that the peak intensities of the middle samples were significantly higher than those of the other two samples. With the given values for permittivity of free space (${\varepsilon}_0=8.854{\times}10^{-12}F{\cdot}m^{-1}$), thickness (d = 1 mm), and area ($A=10{\times}10mm^2$) of the TlBr sample, capacitances of TlBr were 6.9 pF (at $h{\nu}=3eV$) and 4.4 pF (at $h{\nu}=6eV$), respectively. Conclusion: SE and PL measurement and analysis were performed to characterize TlBr samples from the optical perspective. It was observed that dielectric responses of different TlBr samples were slightly different due to the different material properties. PL measurements showed that the middle sample exhibited much stronger PL emission peaks due to the better material quality. From the SE analysis, optical, dielectric constants were extracted, and calculated capacitances were in the few pF range.

• Journal of Adhesion and Interface
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• v.2 no.4
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• pp.32-38
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• 2001

Effects of the ratio of rubber composition on covulcanization and ozone resistance were studied in this study. Specimens used in this study were rubber compounds(specimen-A) blended with various ratio of NR, SBR, BR, IIR, and EPDM, unsaturated rubber compounds(specimen-B) with NR/BR/SBR, and saturated rubber compounds(specimen-C) with NR/IIR/EPDM. PAD adhesion specimen was prepared from vulcanizing specimen-A and B, and specimen-A and C, respectively. Using same adhesion specimen, peel strength was measured and tested ozone resistance. In specimen-A, peel strength was higher with increasing NR ratio for NR and BR contained blends. In other specimen-A containing NR and SBR, the peel strength was also increased with increasing SBR ratio. NR/BR/IIR/EPDM rubber compounds had also better adhesion property than NR/SBR/IIR/EPDM compounds. As more unsaturated rubber was blended, the peel strength was higher but ozone resistance was worse. Optimum ratio of unsaturated and saturated rubbers for the peel strength and ozone resistance was 60/40.