• Title/Summary/Keyword: BR2K

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Characteristics of the Zn-Br Redox Flow Battery using the Different Electrolyte and Membrane (전해액과 격막에 따른 Zn-Br 레독스 흐름 전지의 특성)

  • CHOI, HO-SANG;OH, YONG-HWAN;RYU, CHEOL-HWI;HWANG, GAB-JIN
    • Transactions of the Korean hydrogen and new energy society
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    • v.27 no.4
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    • pp.365-371
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    • 2016
  • Cell performance of the Zn-Br redox flow battery (ZBRFB) using two different type's membrane (Nafion117 and SF-600) was evaluated at $20mA/cm^2$ of current density in 1M (mol/L) $ZnBr_2$ + 2M KCl + 0.3M EMPBr(1-ethyl-1-methyl pyrrolidinium bromide) electrolyte. The average energy efficiencies of ZBRFB were 74.9% and 74.7% for Nafion117 and SF-600, respectively. The electrolyte added the 1-ethyl-3-methylimidazolium dicyanamide (EMICA) as an additive was tested for the electrolyte in ZBRFB using SF-600 at $30mA/cm^2$ of current density. An average energy efficiency of the ZBRFB was 74.5% and 77.4% for the electrolyte non-added EMICA and added 1wt% of EMICA, respectively. ZBRFB using the electrolyte added EMICA was showed the higher performance than that using the electrolyte non-added EMICA.

Extraction Equilibrium of Acrylic Acid by Aqueous Two-Phase Systems Using Hydrophilic Ionic Liquids (친수성 이온성 액체를 이용한 수상이성분계에서의 아크릴산 추출 평형)

  • Lee, Yong Hwa;Lee, Woo Youn;Kim, Ki-Sub;Hong, Yeon Ki
    • Korean Chemical Engineering Research
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    • v.52 no.5
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    • pp.627-631
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    • 2014
  • As an effective method for extraction of acrylic acid, aqueous two-phase systems based on morpholinium ionic liquids were used in this study. Effects of the alkyl chain length of cation in morpholinium ionic liquids on phase diagram and extraction efficiencies were investigated. Experimental results show that aqueous two phase systems can be formed by adding appropriate amount of morpholinium ionic liquids to aqueous $K_2HPO_4$ solutions. It can be found that the ability of morpholinium ionic liquids for phase separation followed the order [HMMor][Br]>[OMMor][Br]>[BMMor][Br]>[EMMor][Br]. There was little difference between binodal curves of imidazolium ionic liquids and those of morpholinium ionic liquids. 50~90% of the extraction efficiency was observed for acrylic acid by aqueous two phase extraction of acrylic acid with morpholinium ionic liquids. It can be concluded that morpholinium ionic liquids/$K_2HPO_4$ were effective for aqueous two phases extraction of acrylic acid comparing to imidazolium ionic liquids/$K_2HPO_4$ systems because of their lower cost.

Antioxidative and Anti-Inflammatory Activities of Salvia plebeia R. Br Extracts (배암차즈기(Salvia plebeia R. Br.)의 항산화 활성 및 항염증효과)

  • Lee, Yeong-Ye;Kang, Soon Ah
    • The Korean Journal of Food And Nutrition
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    • v.33 no.5
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    • pp.483-492
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    • 2020
  • This study provides data to explore functional medicinal food materials that can prevent adult diseases, and verified antioxidant and anti-inflammatory of each solvent fraction of the methanol extract of Salvia plebeia R. Br. in Korea. In the analysis of total phenol content, DPPH radical scavenging ability, and FRAP reduction ability as indicators of antioxidant activity, the methanol fraction and ethyl acetate fraction of the Salvia plebeia R. Br. group showed high antioxidant activity. Ethyl acetate fraction of Salvia plebeia R. Br. methanol extract also showed excellent antioxidative activity as compared with BHT. In the mouse macrophage line Raw 264.7 cells, the NO production ability by LPS treatment was significantly increased in the LPS treatment group compared to the untreated group. In inflammatory reactions induced by LPS treatment in Raw 264.7 cells, inflammatory cytokines (TNF-α, PGE2, IL-1β) and NO production were decreased in the EtOAc fraction and MeOH fraction of the methanol extract of Salvia plebeia R. Br. compared to the case of LPS treatment alone. The anti-inflammatory effect was proved by significantly inhibiting the production of inflammatory cytokines. The present results suggest that Salvia plebeia R. Br. supplementation is beneficial for the suppression of antioxidant and anti-inflammation.

Analysis of LiBr-H$_{2}$O Film Absorption on a Horizontal Tube (수평원관상의 LiBr-H$_{2}$O 액막흡수현상 해석)

  • Park, Il-Seok;Choe, Do-Hyeong
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.20 no.2
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    • pp.670-679
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    • 1996
  • A numerical study for vapor absorption into LiBr-H$_{2}$O solution film flowing over horizontal circular tubes has been carried out. The momentum, energy and diffusion equations, which are parabolized by the boundary- layer approximation, are solved simultaneously for various mass-flow rates and inlet conditions. The results for the velocity, temperature and concentration fields, as well as the heat and mass flux at the free surface are presented. The effects of inlet conditions, i.e., flow rate, temperature and concentration, on the absorption process are also examined and discussed.

Enhancement of ${\beta}$-1,3-Glucan Functionality by Batch and Semi-continuous Typed Specific Carboxylation (회분식 및 반연속식 특이적 카르복실화 반응에 의한 ${\beta}$-1,3-glucan의 기능성 향상)

  • Jeong, Suk-Yun;Kim, Sang-Woo;Lee, Yong-Hwan;Lee, Jae-Hwan;Chang, Pahn-Shick
    • Korean Journal of Food Science and Technology
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    • v.40 no.2
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    • pp.146-151
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    • 2008
  • In this study, batch or semi-continuous reactions, introducing site-specific carboxylic acids in ${\beta}$-1,3-glucan structures, were performed to increase water solubility and gel forming ability, using TEMPO/hypobromite with or without NaBr as catalysts. Regio-selective carboxylic acid formations were determined with infrared (IR) and $^{13}C$ nuclear magnetic resonance (NMR) spectroscopic analyses. The regio-selective reactions with and without NaBr gave oxidation yields of 92.5 and 85.6%, respectively, in the batch type, and yields of 93.9 and 86.4%, respectively, in the semi-continuous type. The reaction times in the batch and semi-continuous reactions without NaBr were delayed by 100 and 150%, respectively, as compared to those with NaBr. A combination of IR and $^{13}C$ NMR analyses were used to confirm the formation of carboxylic acids in ${\beta}$-1,3-glucan. From the batch reactions with and without NaBr, the water solubilities of oxidized products were 50.0 and 55.6%, respectively, and in the semi-continuous reactions they were 52.6 and 53.5%, respectively; while the water solubility of the native ${\beta}$-1,3-glucan was less than 1.0%. Finally, as compared to the native ${\beta}$-1,3-glucan, the gel forming ability of the reaction products was greatly increased irrespective of the presence of NaBr or the reaction type.

Palladium(II) Complexes of Aminophosphines (I). Characterization and Synthesis of $[Pd(L)X_2] with X = Cl^-, Br^-, I^-, NCS^-$ (아미노포스핀류를 포함하는 팔라듐 (II) 착물 (제1보). $[Pd(L)X_2] (X = Cl^-, Br^-, I^-, NCS^-)$의 합성과 성질)

  • Myung-Ki Doh;Bong-Gon Kim
    • Journal of the Korean Chemical Society
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    • v.27 no.4
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    • pp.255-261
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    • 1983
  • Several new $[Pd(L)X_2]$ complexes have been prepared with aminophosphines (L) such as trans-1,2-bis[diphenylphosphino)amino]cyclohexane and 1,2-bis[(diphenylphosphino) amino] propane that contain phosphorus atom as ${\pi}$-electron acceptor, and the bond character of complexes have been investigated by means of infrared and electronic spectroscopy. It was found that thiocyanate ions are N-coordinated possibly due to the steric and electronic influence of the phosphorus atom in aminophosphines that formed seven-membered chelate rings, and that spectrochemical series that is derived from the electronic spectra of the complexes is $NCS^- > Cl^- > Br^- > I^-$

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Effects of Brassica rapa SHI-RELATED SEQUENCE overexpression on petunia growth and development (배추 SHI-RELATED SEQUENCE 유전자 발현이 페튜니아 생장 발달에 미치는 영향)

  • Hong, Joon Ki;Suh, Eun Jung;Lee, Su Young;Song, Cheon Young;Lee, Seung Bum;Kim, Jin A;Lee, Soo In;Lee, Yeon-Hee
    • Journal of Plant Biotechnology
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    • v.42 no.3
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    • pp.204-214
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    • 2015
  • SHI-RELATED SEQUENCE (SRS) genes are plant-specific transcription factors that contain a zinc-binding RING finger motif, which play a critical role in plant growth and development. Among Brassica rapa SRS genes, BrSRS7 and BrLRP1 genes, isolated from shoot apical regions are important regulators of plant growth and development. In order to explore the function of BrSRS genes in horticultural plant growth and development, two constructs containing BrSRS7 and BrLRP1 under the control of a cauliflower mosaic virus 35S promoter were introduced into petunia by Agrobacterium-mediated transformation. The resulting transgenic plants were dwarf and compact plants with reduced plant height and diameter. Additionally, these transgenic plants had upward-curled leaves of narrow width and short internodes. Interestingly, the flower shapes of petunia were different among transgenic plants harboring different kinds of SRS genes. These phenotypes were stably inherited through generations $T_2$ and $T_3$. Semi-quantitative RT-PCR analyses of transgenic plants revealed that BrSRS7 and BrLRP1 regulate expression of gibberellin (GA)- and auxinrelated genes, PtAGL15- and PtIAMT1-related, involved in shoot morphogenesis. These results indicate that the overexpression of BrSRS7 and BrLRP1 genes suppressed the growth and development of petunia by regulating expression of GA- and auxin-related genes. From these data, we deduce that BrSRS7 and BrLRP1 genes play an important role in the regulation of plant growth and development in petunia. These findings suggest that transformation with the BrSRS genes can be applied to other species as a tool for growth retardation and modification of plant forms.

Effects of Bupleuri Radix on OVA-induced Allergic Rhinitis Model of BALB/c mice (柴胡가 OVA로 유발된 BALB/c mice의 알레르기성 비염 모델에 미치는 영향)

  • Lim, Jeong-Min;Heo, Jun;Lee, SungYub;Kim, Jae-Hyun;Lee, Bina;Min, Ju-Hee;Kim, Eun-Young;Jung, Hyuk-Sang;Sohn, Youngjoo
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.29 no.6
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    • pp.467-474
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    • 2015
  • Allergic rhinitis is a growing tendency to increase. Following this tendency, allergic rhinitis is lively studied also in Korean oriental medicine. Bupleuri Radix (BR) has been used for many inflammatory diseases, but experimental backgrounds are not enough to treat allergic rhinitis. So in this study, effects of BR on OVA-induced allergic rhinitis model of BALB/c mice were examined. Thirty two BALB/c mice are equally devided into four groups; control group, OVA group, OVA+BR group, OVA+Cet group. The OVA, OVA+BR and OVA+Cet groups were induced allergic rhinitis by sensitizing to OVA. And then saline solution included BR (10.6 mg/kg body weight) was administered to the OVA+BR group orally. The number of nasal rubbing and nasal sneezing was evaluated for 10 days and later serological and histological changes were analyzed. Serological analysis included the serum levels of cytokines and chemokines (IL-4, IL-5, IL-12, MCP-1, MIP-2), total IgE and OVA-specific IgE levels in serum. Histological analysis included thickness of nasal septum, eosinophil counts changes of nasal mucosa, infiltration of eosinophil in nasal mucosa and histological changes of nasal mucosa. The number of nasal rubbing and nasal sneezing was significantly decreased in the OVA+BR group. The serum levels of IL-4, IL-5, MCP-1, MIP-2 were significantly decreased in the OVA+BR group but the serum levels of IL-1β had not significance. Total IgE and OVA-specific IgE levels in serum were decreased in the OVA+BR group, but total IgE levels in serum had only significance. Thickness of nasal septum, eosinophil counts of nasal mucosa and infiltration of eosinophil in nasal mucosa were significantly decreased in the OVA+BR group. From the results of this study, we think that BR has an effect on improvement of allergic rhinitis by improving nasal rubbing and nasal sneezing, reducing histological changes of nasal mucosa and infiltration of eosinophil in nasal mucosa, inhibiting increasing of the serum levels of cytokines, chemokines and total IgE.

Expression of a Glutathione Reductase from Brassica rapa subsp. pekinensis Enhanced Cellular Redox Homeostasis by Modulating Antioxidant Proteins in Escherichia coli

  • Kim, Il-Sup;Shin, Sun-Young;Kim, Young-Saeng;Kim, Hyun-Young;Yoon, Ho-Sung
    • Molecules and Cells
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    • v.28 no.5
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    • pp.479-487
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    • 2009
  • Glutathione reductase (GR) is an enzyme that recycles a key cellular antioxidant molecule glutathione (GSH) from its oxidized form (GSSG) thus maintaining cellular redox homeostasis. A recombinant plasmid to overexpress a GR of Brassica rapa subsp. pekinensis (BrGR) in E. coli BL21 (DE3) was constructed using an expression vector pKM260. Expression of the introduced gene was confirmed by semi-quantitative RT-PCR, immunoblotting and enzyme assays. Purification of the BrGR protein was performed by IMAC method and indicated that the BrGR was a dimmer. The BrGR required NADPH as a cofactor and specific activity was approximately 458 U. The BrGR-expressing E. coli cells showed increased GR activity and tolerance to $H_2O_2$, menadione, and heavy metal ($CdCl_2$, $ZnCl_2$ and $AlCl_2$)-mediated growth inhibition. The ectopic expression of BrGR provoked the co-regulation of a variety of antioxidant enzymes including catalase, superoxide dismutase, glutathione peroxidase, and glucose-6-phosphate dehydrogenase. Consequently, the transformed cells showed decreased hydroperoxide levels when exposed to stressful conditions. A proteomic analysis demonstrated the higher level of induction of proteins involved in glycolysis, detoxification/oxidative stress response, protein folding, transport/binding proteins, cell envelope/porins, and protein translation and modification when exposed to $H_2O_2$ stress. Taken together, these results indicate that the plant GR protein is functional in a cooperative way in the E. coli system to protect cells against oxidative stress.

Extraction Equilibria of Succinic Acid by Using Aqueous Two Phases System Containing Imidazolium Ionic Liquids and Salts (이미다졸계 이온성액체와 염을 포함한 수상이성분계를 이용한 숙신산의 추출 평형)

  • Lee, Yong Hwa;Kang, Jeong Won;Hong, Yeon Ki;Kim, Ki-Sub
    • Clean Technology
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    • v.20 no.4
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    • pp.349-353
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    • 2014
  • Succinic acid is an important precursor in industries producing biopolymers, pharmaceutical and food additives and green solvents. However, due to the high price of petroleum and the global $CO_2$ emission, the biological production of succinic acid from renewable biomass is a novel process due to the fixation of $CO_2$ into succinate during fermentation. In this study, aqueous two phase systems based on imidazolium ionic liquids/$K_2HPO_4$ were used as an effective separation and concentration process for succinic acid. Experimental results show that aqueous two phase systems can be formed by adding appropriate amount of imidazolium ionic liquids to aqueous $K_2HPO_4$ solutions in the presence of succinic acid. It can be found that the ability of imidazolium ionic liquids for phase separation followed the order [HMIm][Br]${\fallingdotseq}$[OMIm][Br]>[BMIm][Br]>[EMIm][Br]. The maximum value of extraction efficiency for succinic acid was about 90% and the amount of coextracted water into top phase is proportional to the chain length of cation in imidazolium ionic liquids. It was concluded that the aqueous two phase systems composed of imidazolium ionic liquids/$K_2HPO_4$ was effective for the selective extraction and concentration of succinic acid.