• Title/Summary/Keyword: BEA

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Desulfurization of Sulfur Compounds in City-gas using Metal Salt Impregnated Zeolite (금속이온이 담지 된 제올라이트를 이용한 도시가스 내 부취제 제거)

  • Song, Hirn-Ill;Ko, Chang Hyun;Kim, Jae Chang;Kim, Jong-Nam
    • Korean Chemical Engineering Research
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    • v.45 no.2
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    • pp.143-148
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    • 2007
  • In hydrogen production for fuel cell by reforming city-gas, sulfur compounds, odorant in city-gas, are detrimental to reforming catalyst and fuel cell electrodes. We prepared metal salt impregnated ${\beta}-zeolite(BEA)$ to remove sulfur compound in city-gas by adsorption. The sulfur breakthrough adsorption capacity was changed depending on the concentration and species of metal salt. $AgNO_3$ impregnated BEA showed the highest sulfur breakthrough capacity among adsorbents used in this experiment(41.1 mg/g). But metal salt impregnated BEA such as $Ni(NO_3)_2/BEA$, $Fe(NO_3_)_3/BEA$, $Co(NO_3)_2/BEA$ showed a certain amount of sulfur adsorption capacity comparable to $AgNO_3/BEA$. Adsorption temperature effect, desorption study, and x-ray photoelectron spectroscopy analysis revealed that the dominant interaction between metal impregnated adsorbent and sulfur compounds was not chemisorption but physisorption.

Survey on Contamination of Beauvericin and Enniatins in Korean Ginger and Ginger Powder (국내산 생강 및 생강가루의 Beauvericin과 Enniatins 오염도 조사)

  • Lee, Mi Jeong;Lim, Soo Bin;Choi, Jung-Hye;Kim, Jeomsoon;Lee, Theresa;Jang, Ja Yeong
    • Journal of Food Hygiene and Safety
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    • v.37 no.5
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    • pp.347-355
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    • 2022
  • Levels of beauvericin (BEA) and enniatins (ENNs: ENA, ENA1, ENB, and ENB1) were examined in fresh ginger (n = 43) and ginger powder (n = 31) samples from Korea. In the ginger samples, incidence of BEA contamination was highest, at 62.79%, with a maximum detected BEA level of 640.07 ㎍/kg. ENNs in were found in up to 11.63% (ENB, ENB1) of ginger samples, with a maximum detected level of 91.02 ㎍/kg (ENA). In the ginger powders, ENB contamination displayed the highest rate of incidence (70.97%), but the highest level of BEA (1,344.18 ㎍/kg) exceeded that of ENB (413.99 ㎍/kg). The incidences of ENA, ENA1, ENB, and ENB1 presence in ginger powders were 29.03%, 22.58%, 70.97%, and 35.48%, respectively, and their highest detected levels were 220.45, 156.61, 413.99, and 70.29 ㎍/kg, respectively. The incidence of BEA and ENN contamination was higher in ginger powder than in ginger. Respective co-occurrence rates of BEA and ENNs in ginger and ginger powder samples were 16.28% and 64.52%, indicating that the BEA and ENN co-contamination rate was highest in ginger powder as well. This is the first report on the presence and co-occurrence of BEA and ENNs in Korean ginger and ginger powder.

Beauvericin, a cyclic peptide, inhibits inflammatory responses in macrophages by inhibiting the NF-κB pathway

  • Yoo, Sulgi;Kim, Mi-Yeon;Cho, Jae Youl
    • The Korean Journal of Physiology and Pharmacology
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    • v.21 no.4
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    • pp.449-456
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    • 2017
  • Beauvericin (BEA), a cyclic hexadepsipeptide produced by the fungus Beauveria bassiana, is known to have anti-cancer, anti-inflammatory, and anti-microbial actions. However, how BEA suppresses macrophage-induced inflammatory responses has not been fully elucidated. In this study, we explored the anti-inflammatory properties of BEA and the underlying molecular mechanisms using lipopolysaccharide (LPS)-treated macrophage-like RAW264.7 cells. Levels of nitric oxide (NO), mRNA levels of transcription factors and the inflammatory genes inducible NO synthase (iNOS) and interleukin (IL)-1, and protein levels of activated intracellular signaling molecules were determined by Griess assay, semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR), luciferase reporter gene assay, and immunoblotting analysis. BEA dose-dependently blocked the production of NO in LPS-treated RAW264.7 cells without inducing cell cytotoxicity. BEA also prevented LPS-triggered morphological changes. This compound significantly inhibited nuclear translocation of the $NF-{\kappa}B$ subunits p65 and p50. Luciferase reporter gene assays demonstrated that BEA suppresses MyD88-dependent NF-${\kappa}B$ activation. By analyzing upstream signaling events for $NF-{\kappa}B$ activation and overexpressing Src and Syk, these two enzymes were revealed to be targets of BEA. Together, these results suggest that BEA suppresses $NF-{\kappa}B$-dependent inflammatory responses by suppressing both Src and Syk.

Effect of Steam-Treated Zeolite BEA Catalyst in NH3-SCR Reaction (NH3-SCR 반응에서 스팀 처리된 zeolite BEA 촉매의 영향)

  • Park, Ji Hye;Cho, Gwang Hee;Hwang, Ra Hyun;Baek, Jeong Hun;Yi, Kwang Bok
    • Clean Technology
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    • v.26 no.2
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    • pp.145-150
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    • 2020
  • Nitrous oxide (N2O) is one of the six greenhouse gases, and it is essential to reduce N2O by showing a global warming potential (GWP) equivalent to 310 times that of carbon dioxide (CO2). Selective catalytic reduction (SCR) is a technology that converts ammonia into harmless N2 and H2O by using ammonia as a reducing agent to remove NOx, one of the air pollutants; the process also produces high denitrification efficiency. In this study, the Fe-BEA catalyst was steam-treated at 100 ℃ for 2 h before Fe ion exchange in the fixed bed reactor in order to investigate the effect of the steam-treated Fe-BEA catalyst on the NH3-SCR reaction. NH3-SCR reaction test of synthesized catalysts was performed at WHSV = 180 h-1, 370 to 400 ℃ in the fixed bed reactor. The Fe-BEA(100) catalyst steam-treated at 100 ℃ showed a somewhat higher activity than the Fe-BEA catalyst at 370 to 390 ℃. The catalysts were characterized by BET, ICP, NH3-TPD, H2-TPR, and 27Al MAS NMR in order to determine the cause affecting NH3-SCR activity. The H2-TPR result confirmed that the Fe-BEA(100) catalyst had a higher reduction of isolated Fe3+ than the Fe-BEA catalyst, and that the steam treatment increased the amount of isolated Fe3+ as an active species, thus increasing the activity.

Statistical Optimization of Growth Medium for the Production of the Entomopathogenic and Phytotoxic Cyclic Depsipeptide Beauvericin from Fusarium oxysporum KFCC 11363P

  • Lee, Hee-Seok;Song, Hyuk-Hwan;Ahn, Joong-Hoon;Shin, Cha-Gyun;Lee, Gung-Pyo;Lee, Chan
    • Journal of Microbiology and Biotechnology
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    • v.18 no.1
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    • pp.138-144
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    • 2008
  • The production of the entomopathogenic and phytotoxic cyclic depsipeptide beauvericin (BEA) was studied in submerged cultures of Fusarium oxysporum KFCC 11363P isolated in Korea. The influences of various factors on mycelia growth and BEA production were examined in both complete and chemically defined culture media. The mycelia growth and BEA production were highest in Fusarium defined medium. The optimal carbon and nitrogen sources for maximizing BEA production were glucose and $NaNO_3$, respectively. The carbon/nitrogen ratio for maximal production of BEA was investigated using response surface methodology (RSM). Equations derived by differentiation of the RSM model revealed that the production of BEA was maximal when using 108 mM glucose and 25 mM $NaNO_3$.

The Effect of Promoter on the SO2-resistance of Fe/zeolite Catalysts for Selective Catalytic Reduction of NO with Ammonia (NO의 암모니아 선택적 촉매환원반응을 위한 철 제올라이트 촉매의 내황성에 미치는 조촉매 효과)

  • Ha, Ho-Jung;Choi, Joon-Hwan;Han, Jong-Dae
    • Clean Technology
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    • v.21 no.3
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    • pp.153-163
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    • 2015
  • The effects of H2O and residue SO2 in flue gases on the activity of the Fe/zeolite catalysts for low-temperature NH3-SCR of NO were investigated. And the addition effect of Mn, Zr and Ce to Fe/zeolite for low-temperature NH3-SCR of NO in the presence of H2O and SO2 was investigated. Fe/zeolite catalysts were prepared by liquid ion exchange and promoted Fe/zeolite catatysts were prepared by liquid ion exchange and doping of Mn, Zr and Ce by incipient wetness impregnation. Zeolite NH4-BEA and NH4-ZSM-5 were used to adapt the SCR technology for mobile diesel engines. The catalysts were characterized by BET, X-ray diffraction (XRD), SEM/EDS, TEM/EDS. The NO conversion at 200 ℃ over Fe/BEA decreased from 77% to 47% owing to the presence of 5% H2O and 100 ppm SO2 in the flue gas. The Mn promoted MnFe/BEA catalyst exhibited NO conversion higher than 53% at 200 ℃ and superior to that of Fe/BEA in the presence of H2O and SO2. The addition of Mn increased the Fe dispersion and prevented Fe aggregation. The promoting effect of Mn was higher than Zr and Ce. Fe/BEA catalyst exhibited good activity in comparison with Fe/ZSM-5 catalyst at low temperature below 250 ℃.

Beta and Alpha Regularizers of Mish Activation Functions for Machine Learning Applications in Deep Neural Networks

  • Mathayo, Peter Beatus;Kang, Dae-Ki
    • International Journal of Internet, Broadcasting and Communication
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    • v.14 no.1
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    • pp.136-141
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    • 2022
  • A very complex task in deep learning such as image classification must be solved with the help of neural networks and activation functions. The backpropagation algorithm advances backward from the output layer towards the input layer, the gradients often get smaller and smaller and approach zero which eventually leaves the weights of the initial or lower layers nearly unchanged, as a result, the gradient descent never converges to the optimum. We propose a two-factor non-saturating activation functions known as Bea-Mish for machine learning applications in deep neural networks. Our method uses two factors, beta (𝛽) and alpha (𝛼), to normalize the area below the boundary in the Mish activation function and we regard these elements as Bea. Bea-Mish provide a clear understanding of the behaviors and conditions governing this regularization term can lead to a more principled approach for constructing better performing activation functions. We evaluate Bea-Mish results against Mish and Swish activation functions in various models and data sets. Empirical results show that our approach (Bea-Mish) outperforms native Mish using SqueezeNet backbone with an average precision (AP50val) of 2.51% in CIFAR-10 and top-1accuracy in ResNet-50 on ImageNet-1k. shows an improvement of 1.20%.

Synthesis of Optically Active Monoesters via Kinetic Resolution by Chiral Co (Salen) Complex Immobilized on Mesoporous BEA (메조세공 BEA에 고정화된 키랄 Co살렌 착체의 동적분할을 통한 고광학순도의 키랄 모노에스테르 합성)

  • Choi, Seong Dae;Park, Geun Woo;Lee, Gyung Chan;Kim, Geon-Joong
    • Applied Chemistry for Engineering
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    • v.26 no.2
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    • pp.132-137
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    • 2015
  • BEA-zeolite was modified by alkaline solution to introduce mesoporosity in the crystals and the homogeneous chiral Co(III) salen was immobilized in the mesopores. The dinuclear chiral Co(salen)-$GaCl_3$ catalyst immobilized on mesoporous BEA-zeolite showed high activity for the regioselective ring opening of terminal epoxides by carboxylic acids. Various chiral monoester derivatives could be synthesized with moderate enantioselectivity (47~69 ee%) from racemic epoxides through above reaction. When the chiral (S)-ECH was used as a reactant, it was efficiently resolved by carboxylic acid with a high enantioselectivity in the presence of heterogenized chiral salen catalyst, and the ring opened product afforded optically pure monoester epoxide (R)-GB (up to 98 ee%) through the ring closing in the basic solution by elimination of HCl. The heterogeneous catalyst could be fabricated easily, and the catalytic activity was retained for several times reuse without any further regeneration step.

Selective Catalytic Reduction of NOx with Ammonia over Cu and Fe Promoted Zeolite Catalysts (구리 제올라이트와 철 제올라이트 촉매에 의한 질소산화물의 암모니아 선택적 촉매환원반응 특성)

  • Ha, Ho-Jung;Hong, Ju-Hwan;Choi, Joon-Hwan;Han, Jong-Dae
    • Clean Technology
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    • v.19 no.3
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    • pp.287-294
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    • 2013
  • The $NH_3$-selective catalytic reduction (SCR) reaction of NO with excess of oxygen were systematically investigated over Cu-zeolite and Fe-zeolite catalysts. Cu-zeolite and Fe-zeolite catatysts to adapt the SCR technology for mobile diesel engines were prepared by liquid ion exchange and incipient wetness impregnation of $NH_4$-BEA and $NH_4$-ZSM-5 zeolites. The catalysts were characterized by BET, XRD, FE-TEM (field emission transmission electron microscopy) and SEM/EDS. The SCR examinations performed under stationary conditions showed that the Cu-exchanged BEA catalyst revealed pronounced performance at low temperatures of $200{\sim}250^{\circ}C$. With respect to the Fe-zeolite catalyst, the Cu-zeolite catalyst showed a higher activity in the SCR reaction at low temperatures below $250^{\circ}C$. BEA zeolite based catalyst exhibited good activity in comparison with ZSM-5 zeolite based catalyst at low temperatures below $250^{\circ}C$.

Study on the Vasorelaxant Mechanism of the Butanol Extract of Euonymus alatus (귀전우(鬼箭羽) 부탄올 추출물의 혈관이완 기전에 대한 연구)

  • Li, Xiang;Kang, Dae-Gill;Lee, Jun-Kyoung;Kim, Seung-Ju;Choi, Deok-Ho;Lee, Kye-Bok;Cui, Hao-Zhen;Yeom, Ki-Bok;Lee, Ho-Sub
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.22 no.1
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    • pp.148-154
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    • 2008
  • The butanol extract of Euonymus alatus (BEA) induced dose-dependent relaxation of phenylephrine-precontracted aorta, which was abolished by removal of functional endothelium. Pre-treatment of the endothelium-intact aortic tissues with $N^G-nitro-L-arginine methylester$ (L-NAME), and 1 H-[1,2,4]-oxadiazole- [$4,3-{\alpha}$]-quinoxalin-1-one (ODQ) inhibited the relaxation induced by BEA, respectively. BEA-induced vascular relaxation was not blocked by glibenclamide, tetraethylammonium (TEA), indomethacin, atropine, propranolol, verapamil, and diltiazem, respectively. Moreover, BEA inhibits phenylephrine-induced vascular constriction in a dose-dependent manner. These results suggest that BEA relaxes vascular smooth muscle via endothelium-dependent nitric oxide/cGMP signaling.