• 제목/요약/키워드: Oxygen membrane

검색결과 880건 처리시간 0.028초

Phosphorus removal by lime-natural mineral dissolved solutions

  • Joohyun, Kim;Sunho, Yoon;Jueun, Jung;Sungjun, Bae
    • Membrane and Water Treatment
    • /
    • 제14권1호
    • /
    • pp.27-33
    • /
    • 2023
  • In previous studies, solely ferric (Fe3+) and calcium (Ca2+) ions were commonly used for removal of PO4-P (considered as T-P in this study) in wastewater via chemical precipitation. Herein, the removal of total phosphorus (T-P) in wastewater was performed using various mineral and lime dissolved solutions. The dissolution kinetics of different minerals (feldspar, olivine, elvan, illite, sericite, and zeolite) and lime was compared and used their solutions for T-P removal of real wastewater. The highest T-P removal (almost 90%) was obtained by the lime dissolved solution and followed by zeolite, illite, feldspar, and others. We observed a significant co-relationship (R of 0.96) between the amount of initial Ca2+ and T-P removal. This was induced by formation of hydroxyapatite-like mineral via Ca-P precipitation reaction at high pH solution. Furthermore, additional removal of suspended solid (SS) and chemical oxygen demand (COD) was achieved by only lime dissolved solution. Finally, the lime-feldspar dissolved solutions were prepared at different ratios (10-50%), which showed a successive T-P removal up to two times by samples of 40 and 50%.

Effects of Panax ginseng and ginsenosides on oxidative stress and cardiovascular diseases: pharmacological and therapeutic roles

  • Hyun, Sun Hee;Bhilare, Kiran D.;In, Gyo;Park, Chae-Kyu;Kim, Jong-Hoon
    • Journal of Ginseng Research
    • /
    • 제46권1호
    • /
    • pp.33-38
    • /
    • 2022
  • Traditionally, Asian ginseng or Korean ginseng, Panax ginseng has long been used in Korea and China to treat various diseases. The main active components of Panax ginseng is ginsenoside, which is known to have various pharmacological treatment effects such as antioxidant, vascular easing, anti-allergic, anti-inflammatory, anti-diabetes, and anticancer. Most reactive oxygen species (ROS) cause chronic diseases such as myocardial symptoms and cause fatal oxidative damage to cell membrane lipids and proteins. Therefore, many studies that inhibit the production of oxidative stress have been conducted in various fields of physiology, pathophysiology, medicine and health, and disease. Recently, ginseng or ginsenosides have been known to act as antioxidants in vitro and in vivo results, which have a beneficial effect on preventing cardiovascular disease. The current review aims to provide mechanisms and inform precious information on the effects of ginseng and ginsenosides on the prevention of oxidative stress and cardiovascular disease in animals and clinical trials.

글루타메이트에 의해 산화적 스트레스를 받은 HT22 세포에서 핑거루트의 신경세포 보호활성 (Neuroprotective Activity of Boesenbergia rotunda Against Glutamate Induced Oxidative Stress in HT22 Cells)

  • 김은서;마충제
    • 생약학회지
    • /
    • 제53권2호
    • /
    • pp.79-86
    • /
    • 2022
  • Excessive glutamate causes oxidative stress in neuronal cells, which can cause degenerative neurological disorders. We tried to find medicinal plant showed neuroprotective activity by using glutamate-injured HT22 cell as a model system. In this study, we found that Boesenbergia rotunda methanol extract showed neuroprotective activity against glutamate induced neurotoxicity in mouse hippocampal HT22 cells. B. rotunda methanol extract suppressed the formation of reactive oxygen species and decreased intracellular Ca2+concentration. Also, B. rotunda made mitochondrial membrane potential maintain to normal levels. In addition, B. rotunda increased total glutathione amount and activated antioxidative enzyme such as glutathione reductase and glutathione peroxidase compared to glutamate-treated groups. These results suggested that B. rotunda decreased neuronal cell death damaged by high concentrations of glutamate treatment, via antioxidative mechanism and might be one of candidate of development of new drug to treat neurodegenerative disease such as Alzheimer's disease.

Selective removal of cationic dye pollutants using coal ash-derived zeolite/zinc adsorbents

  • Chatchai Rodwihok;Mayulee Suwannakaew;Sang Woo Han;Siyu Chen;Duangmanee Wongratanaphisan;Han S. Kim
    • Membrane and Water Treatment
    • /
    • 제14권3호
    • /
    • pp.121-128
    • /
    • 2023
  • This study introduces a NaOH/Zn-assisted hydrothermal method for the synthesis of zeolites derived from coal ash (CA). A zeolite/Zn adsorbent is successfully prepared by the activation of CA with NaOH and Zn; it is characterized by a high surface area and a negative surface charge.Methylene blue (MB) and methyl orange (MO) are selected as dye pollutants, and their adsorption onto the zeolite/Zn adsorbent is investigated. Results show the high adsorption capacities of MB and MO and that the negative surface charge facilitates electrostatic interactions between the adsorbates and adsorbents. The zeolite/Zn adsorbents shows the selective adsorption of positively charged dye MB via electrostatic interactions between the =NH+ group (positive dipole) and the oxygen functional group of the adsorbents (negative dipole). The selectivity for the positively charged dye is sufficiently high, with the removal efficiency reaching 99.41% within 10 min. By contrast, the negatively charged dye MO exhibits negligible absorption. These findings confirm the role of electrostatic interactions in the adsorption of MB, in addition to the effect of a large surface area. The results of this study are expected to facilitate the development of simple, eco-friendly, and cost-effective zeolite-based adsorptive composites from CA residuals for the selective removal of dye pollutants from CA waste.

Differential cytotoxic effects of fenbendazole on mouse lymphoma EL-4 cells and spleen cells

  • Haebeen Jung;You-Jeong Lee;Hong-Gu Joo
    • 대한수의학회지
    • /
    • 제63권1호
    • /
    • pp.2.1-2.7
    • /
    • 2023
  • Fenbendazole (FBZ) is a benzimidazole anthelmintic widely used to treat parasitic infections. The anticancer effect of FBZ has been recently highlighted leading to its consideration as a potential anticancer agent. Although previous studies have demonstrated the effect of FBZ on cancer cells, there is a paucity of studies on the effect of FBZ on lymphoma cells and normal immune cells. Herein, we investigated the effects of FBZ on a mouse lymphoma cell line, EL-4 cells, and spleen cells, using vincristine as a positive control. The cellular metabolic activity of EL-4 cells was decreased by FBZ, but that of the spleen cells was not decreased. Moreover, FBZ reduced the mitochondrial membrane potential and induced reactive oxygen species production in EL-4 cells, but not in spleen cells. FBZ induced G2/M phase arrest and increased the sub G0/G1 phase ratio, indicating apoptosis. Furthermore, compared to the control cells, the reactivity of spleen cells pretreated with FBZ to lipopolysaccharide was maintained. In summary, FBZ is cytotoxic to EL-4 cells, but not to spleen cells. This study provides experimental evidence that FBZ exerts an anticancer effect, and less cytotoxic effects and functional damage to normal spleen cells.

마우스 림프종세포에 대한 disulfiram/copper의 항암증진효과 (Synergistic anticancer activity of disulfiram/copper against mouse lymphoma cells)

  • 정해빈;주홍구
    • 대한수의학회지
    • /
    • 제62권1호
    • /
    • pp.3.1-3.7
    • /
    • 2022
  • Disulfiram (DSF) is a marketed drug to treat patients with alcohol dependence by inhibiting aldehyde dehydrogenase. Over the last few decades, DSF has been shown to have anticancer effects through different mechanisms. Moreover, this effect can be elevated when used with copper (Cu). Subsequent studies have been conducted on various cancers, but few on lymphoma. This study investigated the anticancer effects of DSF on lymphoma and how this effect changed when treated with Cu. DSF synergistically decreased the metabolic activity of EL4 lymphoma cells when combined with Cu. At 1 µM of DSF alone, the metabolic activity of EL4 cells decreased by 49% compared to the control, whereas it decreased by 87% with a DSF + CuCl2 treatment. Rhodamine 123 and 2',7'-dichlorofluorescein diacetate staining showed that DSF induced the reduction of the mitochondrial membrane potential and promoted the production of reactive oxygen species. In particular, the combined treatment of DSF + Cu induced cell death based on multiple assays, including annexin V-fluorescein isothiocyanate/propidium iodide staining. Overall, DSF has anticancer effects on lymphoma cells and exhibits synergistic effects when combined with Cu. This study provides some valuable information to broaden the use of DSF in clinics and basic research.

Free Radical Scavenging and Antioxidant Activities of Water Extracts from Amannia multiflora, Amannia coccinea, Salix gracilistyla Inhabiting Along the Nakdong River (Republic of Korea)

  • Jayasingha Arachchige Chathuranga Chanaka Jayasingha;Mi-Hwa Lee;Chang-Hee Kang;Yung Hyun Choi;Gi-Young Kim
    • 한국자원식물학회:학술대회논문집
    • /
    • 한국자원식물학회 2022년도 추계학술대회
    • /
    • pp.31-31
    • /
    • 2022
  • Plant-derived antioxidants are used as a healthy diet and are known to inhibit various human diseases. In this study, we investigated free radical scavenging and antioxidant activity of extracts from three plants (Ammannia multiflora, Ammannia coccinea and Salix gracilistyla) with the most DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity from 196 plant extracts inhabiting along Nakdong River in Republic of Korea. The three extracts also have strong total antioxidant activity. Moreover, the extracts inhibited hydrogen peroxide (H2O2)-induced reactive oxygen species production and depolarized mitochondrial membrane potential in RAW264.7 macrophages. In zebrafish larvae, 2',7'-dichlorodihydrofluorescein diacetate (DCFDA) fluorescent intensity, induced by H2O2, was markedly reduced by the extracts of A. multiflora, A. coccinea and S. gracilistyla. Meanwhile, the extracts were upregulated Nrf2 and HO-1 expression, and an HO-1 inhibitor reversed the extract-induced oxidative responses both in vivo and in vitro. The data suggest that the extracts of A. multiflora, A. coccinea, and S. gracilistyla exert potential free radical scavenging and antioxidant capacities both in vivo and in vitro by activating the Nrf2/HO-1 signaling pathway.

  • PDF

지속 가능한 에너지 시스템 구축을 위한 전기분해 수소 생산 플랜트 초기 건설비용 예측 (Predicting Initial Construction Costs of Electrolysis Hydrogen Production Plants for Building Sustainable Energy Systems)

  • 강성욱;김준헌;박종화;조대명
    • 한국수소및신에너지학회논문집
    • /
    • 제35권3호
    • /
    • pp.257-268
    • /
    • 2024
  • Hydrogen serves as a clean energy source with potential applications across various sectors including electricity, transportation, and industry. In terms of policy and economic support, governmental policy backing and economic incentives are poised to accelerate the commercialization and expansion of hydrogen energy technologies. Hydrogen energy is set to become a cornerstone for a sustainable future energy system. Additionally, when constructing hydrogen production plants, economic aspects must be considered. The essence of hydrogen production plants lies in the electrolysis of water, a process that separates water into hydrogen and oxygen using electrical energy. The initial capital expenditure (CAPEX) for hydrogen production plants can vary depending on the electrolysis technology employed. This study aims to provide a comprehensive understanding of hydrogen production technologies as well as to propose a method for predicting the CAPEX of hydrogen production plants.

Research and Optimization of Four Serpentine-Wave Flow Fields in PEMFC

  • Fayi Yan;He Lu;Jian Yao;Xuejian Pei;Xiang Fan
    • Journal of Electrochemical Science and Technology
    • /
    • 제15권3호
    • /
    • pp.373-387
    • /
    • 2024
  • The layout of the cathode flow field largely determines the net output power of the proton exchange membrane fuel cell (PEMFC). To make the normal mass transfer effect best, the longitudinal channel was waved based on four serpentine flow channels, and the effects of sag depth and longitudinal channel width on the output efficiency of the cell were explored. The results show that the wave channel design systematically enhances the forced convection between adjacent channels, which can prevent a large zone of oxygen starvation zone at the outlet of the channel. The increase of the normal velocity in the gas transmission process will inevitably induce a significant enhancement of the mass transfer effect and obtain a higher current density in the reaction zone. For the longitudinal channel width, it is found that increasing its size in the effective range can greatly reduce the channel pressure drop without reducing the output power, thereby improving the overall efficiency. When the sag depth and longitudinal channel width gradient are 0.6 mm and 0.2 mm respectively, PEMFC can obtain the best comprehensive performance.

수정된 폴리올 방법을 적용하여 합성한 PtM 촉매들의 산소환원반응성 연구 (A Study on Oxygen Reduction Reaction of PtM Electrocatalysts Synthesized by a Modified Polyol Process)

  • 양종원;현규환;추천호;권용재
    • 공업화학
    • /
    • 제25권1호
    • /
    • pp.78-83
    • /
    • 2014
  • 본 연구에서는 수정된 폴리올법에 의해 합성된 백금-이트륨 및 백금-니켈 합금 촉매들의 성능 및 특성 평가를 진행하였다. 그렇게 합성된 합금 촉매들은 고분자전해질연료전지의 공기극 촉매로 사용되며 그 촉매들의 산소환원반응성 및 연료전지의 전기적 성능이 측정되고 상업적으로 사용되는 백금 촉매와 해당하는 결과들이 비교되었다. 성능 및 특성 비교를 위해, 백금 합금 촉매들의 입자크기와 분포는 투과전자현미경에 의해 관측되었고 활성표면적은 반복주사 전압-전류법에 의해 측정되었으며 그들의 산소환원반응성 및 연료전지의 전기적 성능은 회전원판 및 회전-고리 원판전극을 이용한 선형주사 전압-전류법 및 완전지 테스트를 통해 평가되었다. 그 결과 백금 합금 촉매들의 구조적 특성인 입자크기 및 분포 및 활성표면적은 상용 백금 촉매와 그 특성이 비슷하였다. 촉매들의 산소환원반응성의 경우에도 백금 합금 촉매들은 상용 백금 촉매와 비슷하거나 더 나은 반파장전위, 속도론적 전류밀도, 산소분자당 전이되는 전자수, 과산화수소 생성율을 나타내었다. 촉매의 구조적 특성 및 산소환원반응성에 입각해서 완전지 성능을 평가했을 때, 백금 합금 촉매들은 상용백금 촉매보다 더 우수한 0.6 V에서 전류밀도 및 최대출력밀도 값을 나타내었다. 이를 토대로 수정된 폴리올법에 의해 합성된 백금 합금 촉매들은 상용백금 촉매보다 비슷하거나 우수한 산소환원반응성 및 완전지 성능을 가질 수 있음을 제시하였다.