Drought is the most serious abiotic stress, which significantly reduces crop productivity. The phytohormone ABA plays a pivotal role in regulating stomatal closing upon drought stress. Here, we ...characterized the physiological function of AtBBD1, which has bifunctional nuclease activity, on drought stress. We found that AtBBD1 localized to the nucleus and cytoplasm, and was expressed strongly in trichomes and stomatal guard cells of leaves, based on promoter:GUS constructs. Expression analyses revealed that
and
are induced early and strongly by ABA and drought, and that
is also strongly responsive to JA. We then compared phenotypes of two
-overexpression lines (
-OX), single knockout
, and double knockout
plants under drought conditions. We did not observe any phenotypic difference among them under normal growth conditions, while OX lines had greatly enhanced drought tolerance, lower transpirational water loss, and higher proline content than the WT and KOs. Moreover, by measuring seed germination rate and the stomatal aperture after ABA treatment, we found that
-OX and
plants showed significantly higher and lower ABA-sensitivity, respectively, than the WT. RNA sequencing analysis of
-OX and
plants under PEG-induced drought stress showed that overexpression of
enhances the expression of key regulatory genes in the ABA-mediated drought signaling cascade, particularly by inducing genes related to ABA biosynthesis, downstream transcription factors, and other regulatory proteins, conferring
-OXs with drought tolerance. Taken together, we suggest that AtBBD1 functions as a novel positive regulator of drought responses by enhancing the expression of ABA- and drought stress-responsive genes as well as by increasing proline content.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Cisplatin, a platinum-containing alkylating agent, is used in the treatment of various tumors owing to its potent antitumor activity. However, it causes permanent and adverse effects, particularly ...hearing loss and depletion of ovarian reserve. Until recently, there were no clinically available protective agents to mitigate the adverse side effects of cisplatin-induced cytotoxicity. In 2022, sodium thiosulfate (STS) was approved by the Food and Drug Administration for mitigating hearing loss in children and adolescents undergoing cisplatin treatment. Consequently, our investigation aimed to determine if STS could protect ovarian reserve against cisplatin-induced gonadotoxicity. In an ex vivo culture, the cisplatin-only group exhibited a loss of primordial follicles, while post-STS administration after cisplatin exposure effectively protected primordial follicles. However, when post-STS was administrated either 6 or 4 h after cisplatin exposure, it did not confer protection against cisplatin-induced gonadotoxicity in postnatal day 7 or adolescent mouse models. Immunofluorescence assays using γH2AX and cPARP revealed that oocytes within primordial follicles exhibited DNA damage after cisplatin exposure, irrespective of post-STS administration. This underscores the rapid and heightened sensitivity of oocytes to gonadotoxicity. In addition, oocytes demonstrated an increased expression of pCHK2 rather than pERK, suggesting that the pathway leading to oocyte death differs from the pathway observed in the inner ear cell death following cisplatin exposure. These results imply that while the administration of STS after cisplatin is highly beneficial in preventing hearing loss, it does not confer a protective effect on the ovaries in mouse models.
안트라퀴논과 템포 활물질 기반 수계 유기 레독스 흐름 전지에서의 멤브레인 효과 이원미; Wonmi Lee; 권용재 ...
Korean Chemical Engineering Research(HWAHAK KONGHAK), 57(5),
10/2019, Volume:
57, Issue:
5
Journal Article
Peer reviewed
Open access
본 연구에서는 유기물인 안트라퀴논(AQDS)와 템포(TEMPO) 를 활물질로 사용하고 N 중성 전해질 기반 수계 유기레독스 흐름전지 성능이 멤브레인에 따라 어떻게 영향을 받는지 분석하였다. 안트라퀴논과 템포 모두 중성 전해질인 염화칼륨(KCl) 전해질에 대해 높은 전자전달성(0.068 V의 산화 반응 및 환원 반응의 피크 전위차) 및 셀전압(1.17 ...V)을 얻을 수 있었다. 성능비교를 위해 사용한 멤브레인으로, 상용 양이온 교환막 중 하나인 Nafion 212를 사용하였을 때, 0.1M 활물질을 1 M 염화칼륨 전해질에 용해해서 작동한 레독스 흐름전지 완전지 테스트를 통해, 전류효율 97%, 전압 효율 59%의 성능을 나타내었지만, 방전 용량(discharge capacity)은 4 사이클에서 0.93 Ah·L -1 로 이론 용량(2.68 Ah·L -1 )의 35%를 도달하였으며, 총 10사이클 동안 방전 용량의 용량 손실율(capacity loss rate)은 0.018 Ah·L-1/cycle이다. 그 외에도 Nafion 117 멤브레인, SELEMION CSO 멤브레인을 사용하여 단전지 성능을 테스트하였을 때, 오히려 저항 증가 및 투과 유도로 인해 더 큰 용량 손실을 이끌었다.
In this study, the evaluation of performance of AORFB using anthraquinone derivative and TEMPO derivative as active materials in neutral supporting electrolyte with various membrane types was performed. Both anthraquinone derivative and TEMPO derivative showed high electron transfer rate (the difference between anodic and cathodic peak potential was 0.068 V) and the cell voltage is 1.17 V. The single cell test of the AORFB using 0.1 M active materials in 1 M KCl solution with using Nafion 212 membrane, which is commercial cation exchange membrane was performed, and the charge efficiency (CE) was 97% and voltage efficiency (VE) was 59%. In addition, the discharge capacity was 0.93 Ah·L -1 which is 35% of theoretical capacity (2.68 Ah·L -1 ) at 4 th cycle and the capacity loss rate was 0.018 Ah·L -1 /cycle during 10 cycles. The single cell tests were performed with using Nafion 117 membrane and SELEMION CSO membrane. However, the results were more not good because of increased resistance because of thicker thickness of membrane and increased cross-over of active materials, respectively.
메틸렌블루와 바나듐을 활물질로 활용한 수계 유기 레독스 흐름 전지의 성능 평가 이원미; Wonmi Lee; 권용재 ...
Korean Chemical Engineering Research(HWAHAK KONGHAK), 56(6),
12/2018, Volume:
56, Issue:
6
Journal Article
Peer reviewed
Open access
본 연구에서는 염료 물질 중 하나인 메틸렌 블루(methylene blue)를 수계 레독스 흐름 전지의 활물질로 처음으로 도입하였다. Methylene blue의 레독스 전위는 pH가 높아짐에 따라 음의 방향으로 이동하는 것을 확인할 수 있었다. 이 methylene blue를 음극 활물질로 활용하고, 양극 활물질로는 바나듐(vanadium) 을 활용하여 ...산 전해질을 기반으로 셀 성능 평가를 진행하였다. Methylene blue/V 4+ 레독스 조합의 산 전해질에 대한 셀 전압은 0.45 V로 낮으며, Methylene blue의 물에 대한 용해도 또한 0.12 M로 굉장히 낮다. 이에 따라 0.0015 M의 낮은 농도로 단전지 셀 성능을 평가하였으며, Nafion 212 멤브레인을 사용하여 0~0.8 V 컷-오프 전압으로 1 mA/㎠ 전류밀도 하에서 4 cycle에서 충방전 효율 96.67%, 전압효율 88.83%, 에너지효율 85.87%, 방전 용량(0.0500 Ah·L -1 )의 성능을 보였으며, 낮은 방전용량은 활물질의 낮은 농도에 의한 것이므로 활물질인 메틸렌 블루의 농도를 0.1 M로, 전류밀도는 10 mA/㎠로 더 높였을 때 4 cycle에서 CE 99%, VE 85%, EE 85%의 효율로 더 높은 방전 용량(3.8122 Ah·L -1 )을 도출함을 확인할 수 있었다.
In this study, methylene blue which is one of dye materials was introduced as active material for aqueous redox flow battery. The redox potential of methylene blue was shifted to negative direction as pH increased. The full-cell performance was evaluated by using methylene blue as the negative active material and vanadium as the positive active material with acid supporting electrolytes. The cell voltage of methylene blue/V 4+ is very low (0.45 V). In addition, the maximum solubility of methylene blue in water is only 0.12 M. Therefore, the cell test was performed with very low concentration (0.0015 M methylene blue, 0.15 M V 4+ ) at first time. Cut-off voltage range was 0 to 0.8 V and 1 mA·cm -2 current density was adopted during cycling. As a result, current efficiency (CE) was 99.67%, voltage efficiency (VE), 88.83% and energy efficiency (EE) was 85.87% and discharge capacity was (0.0500 Ah·L -1 ) at 4 cycle. In addition, the cell test was performed with increased concentration (0.1 M methylene blue, 0.15 M V 4+ ) with 10 mA·cm -2 current density, leading to higher discharge capacity (3.8122 Ah·L -1 ) with similar efficiency (CE=99%, VE=85%, EE=85% at 4 cycle).
수계 유기 레독스 흐름 전지 성능에서의 첨가제 효과 추천호; Cheonho Chu; 이원미 ...
Korean Chemical Engineering Research(HWAHAK KONGHAK), 57(6),
12/2019, Volume:
57, Issue:
6
Journal Article
Peer reviewed
Open access
본 연구에서는 퀴노잘린(quinoxaline)과 페로시아나이드(ferrocyanide)를 활물질로 활용한 알칼리 전해질 기반 수계유기 레독스 흐름전지에 대해 다양한 첨가제를 적용하여 성능을 비교하는 실험을 진행하였다. 퀴노잘린(quinoxaline)의 경우 염화칼륨(KCl) 전해질보다는 수산화칼륨(KOH) 전해질에서의 레독스 전위(-0.97 V)가 더 ...작은 위치에 있으며, 이에 따라 KOH 전해질에 대해 페로시아나이드와 조합을 이루었을 때, 셀 전압 값은 1.3 V로 높게 나타났다. 상용 양이온 교환막 중 하나인 Nafion 117 멤브레인을 사용하였을 때, 퀴노잘린(quinoxaline)의 부반응 현상을 반전지 상에서 관찰 할 수 있었으며, 이에 따라 충방전 자체가 잘 되지 않는 문제점이 있다. 따라서, 문제점이 되는 퀴노잘린(quinoxaline)의 부반응을 해결하기 위해 친전자체와 친핵체 중 하나인 포타슘설페이트(K 2 SO 4 )와 포타슘아이오다이드(KI)를 사용하였으며, 포타슘아이오다이드(KI)를 사용하였을 때, 용량 손실율 측면에서 포타슘 아이오다이드(KI)를 첨가제로 넣지 않았을 때(0.29 Ah·L -1 per cycle) 보다 더 낮은 용량 손실율(0.21 Ah·L -1 per cycle)로 더 높은 용량 유지율을 보였다.
In this study, the effect of additives on the performance of aqueous organic redox flow battery (AORFB) using quinoxaline and ferrocyanide as active materials in alkaline supporting electrolyte is investigated. Quinoxaline shows the lowest redox potential (-0.97 V) in KOH supporting electrolyte, while when quinoxaline and ferrocyanide are used as the target active materials, the cell voltage of this redox combination is 1.3 V. When the single cell tests of AORFBs using 0.1 M active materials in 1 M KCl supporting electrolyte and Nafion 117 membrane are implemented, it does not work properly because of the side reaction of quinoxaline. To reduce or prevent the side reaction of quinoxaline, the two types of additives are considered. They are the potassium sulfate as electrophile additive and potassium iodide as nucleophilie additive. Of them, when the single cell tests of AORFBs using potassium iodide as additive dissolved in quinoxaline solution are performed, the capacity loss rate is reduced to 0.21 Ah·L -1 per cycle and it is better than that of the single cell test of AORFB operated without additive (0.29 Ah·L -1 per cycle).
본 연구에서는 유기물인 메틸 바이올로겐(methyl viologen, MV)과 템폴(4-hydroxy-TEMPO, TEMPOL)을 활물질로 사용하고 NaCl의 중성 전해질 기반 수계 유기 레독스 흐름전지 성능이 멤브레인에 따라 어떻게 영향을 받는지 분석하였다. 메틸 바이올로겐(MV)과 템폴(TEMPOL)은 중성 전해질인 염화나트륨(NaCl) 전해질에 대해 ...높은 셀전압(1.37 V)을 얻을 수 있다. 성능 비교를 위해 사용한 멤브레인은 두 가지이다. 첫째로, 상용 양이온 교환막 중 하나인 Nafion 117를 사용하였을 때 성능은 첫번째 사이클에서 충전만 일어났을 뿐 그 후 높은 저항 때문에 완전지가 작동하지 않았다. 하지만 두번째로 사용한 Fumasep 음이온 교환막(FAA-3-50)은 Nafion 117 멤브레인을 사용했을 때와는 다르게 비교적 안정적인 충방전 사이클링을 보였다. 전류 밀도 40 mA·cm -2 , 컷-오프 전압 0.55~1.7 V에서 전류 효율(charge efficiency)은 97%, 전압 효율(voltage efficiency)은 78%로 높게 나타났다. 방전 용량(discharge capacity)은 10사이클에서 1.44 Ah·L -1 로 이론 용량(2.68 Ah·L -1 )의 54%를 나타내었다. 방전 용량의 용량 손실율(capacity loss rate)은 0.0015 Ah·L-1/cycle 로 나타났다. 순환주사전류 실험을 통해 Nafion 117 멤브레인과 Fumasep 음이온 교환막 사이의 이러한 성능차이는 활물질의 크로스 오버(cross over) 현상으로 인한 방전 용량 손실이 아닌 멤브레인과 활물질의 화학적 반응으로 인한 저항 증가가 원인임을 파악할 수 있었다.
In this study, the evaluation of performance of AORFB using methyl viologen and TEMPOL as organic active materials in neutral supporting electrolyte (NaCl) with various membrane types was performed. Using methyl viologen and TEMPOL as active materials in neutral electrolyte solution, the cell voltage is 1.37V which is relatively high value for AORFB. Two types of membranes were examined for performance comparison. First, when using Nafion 117 membrane which is commercial cation exchange membrane, only the charge process occurred in the first cycle and the single cell couldn’t work because of its high resistance. However, when using Fumasep anion exchange membrane (FAA-3-50) instead of Nafion 117 membrane, the result was obtained as the totally different charge-discharge graphs. When current density was 40mA·cm -2 and cut off voltage range was from 0.55 V to 1.7 V, the charge efficiency (CE) was 97% and voltage efficiency (VE) was 78%. In addition, the discharge capacity was 1.44 Ah·L -1 which was 54% of theoretical capacity (2.68 Ah·L -1 ) at 10th cycle and the capacity loss rate was 0.0015 Ah·L -1 per cycle during 50 cycles. Through cyclic voltammetry test, it seems that this difference in the performance between the full cell using Nafion 117 membrane and Fumasep anion exchange membrane came from increasing resistance due to chemical reaction between membrane and active material, not the capacity loss due to cross-over of active material through membrane.
본 연구에서는 Anthraquinone-2,7-disulfonic acid (2,7-AQDS)와 Tiron을 수계 레독스 흐름 전지 음극 및 양극 활물질로 사용하며 기존의 황산 전해질 대신 중성인 염화암모늄 (NH 4 Cl)을 전해질로 도입하였다. 이렇게 전해질을 변경함으로써, 황산 전해질의 낮은 셀 전압(0.76 V)을 1.01 V까지 향상시킬수 있다. ...성능 최적화를 위해 염화암모늄 전해질에 0.1M로 활물질 농도를 맞춰 컷-오프 전압에 변화를 주며 완전지셀 성능을 평가하였다. 0.2~1.6 V 구간의 컷-오프 전압으로 40 mA/㎠하에서 20 사이클 동안 완전지셀을 테스트한 결과, 충전 동안 수소가 발생하였다. 이에 컷-오프 전압 조절로 충전 전압을 낮춰서 수소 발생을 제한하고자 0.2~1.2 V 구간으로 40 mA/㎠하에서 완전지셀 테스트를 진행하였다. 수소 발생은 없었으며, 전류 효율 99%, 방전 용량 3.3 Ah/L의 성능을 보였다.
In this study, anthraquinone-2,7-disulfonic acid (2,7-AQDS) is used as negative active material and Tiron is used as positive active material for aqueous redox flow battery (RFB). In previous results that used the 2,7-AQDS and Tiron, sulfuric acid (H 2 SO 4 ) was a supporting electrolyte. However, in this study, ammonium chloride (NH 4 Cl) is suggested as the electrolyte for the first time. By changing the supporting electrolyte from H 2 SO 4 to NH 4 Cl, the cell voltage of RFB is improved from 0.76 V to 1.01 V. To investigate the effect of NH 4 Cl supporting electrolyte of the performance of RFB, the full-cell tests of RFB using 2,7-AQDS and Tiron that are dissolved in NH 4 Cl supporting electrolyte are carried out, while cut-off voltage range is a main parameter to determine their performance. When the cut-off voltage range is 0.2~1.6 V, the hydrogen evolution occurs during charging step. To address the side reaction effect, the cut-off voltage range is changed to 0.2~1.2 V. When the revised cut-off voltage range is used and the current density of 40 mA/㎠ is applied, hydrogen evolution is not observed and the optimal RFB shows the charge efficiency of 99% and discharge capacity of 3.3 Ah/L at 10cycle.
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•Mixed NQ derivatives and FeCN are introduced as active materials for AORFB.•The solubility of NQ-SO is enhanced with mixing NQ-S and Lawsone (NQ-OH).•–SO32− groups and polar-polar ...interactions induce the solubility increase of NQ-SO.•Optimal Lawsone to NQ-S ratio is determined by the hygroscopic properties of –SO32−.•Discharge capacity and SOC of AORFB using NQ-SO and FeCN is 40.3 Ah·L−1 and 83%.
Mixture of 1,2-naphthoquinone-4-sulfonic acid sodium salt (NQ-S) and 2-hydroxy-1,4-naphthoquinone (Lawsone) is used as negative active species for aqueous organic redox flow battery (AORFB), while ferrocyanide (FeCN) is considered as positive active species in alkaline electrolyte. NQ-S is initially transformed to NQ-OH that has the same chemical structure with Lawsone by the nucleophilic attack under potassium hydroxide (KOH) electrolyte. The mixture of NQ-S and Lawsone (NQ-SO) has a higher solubility in KOH electrolyte (1.26 M in 1 M KOH) than the individual NQ-SO and NQ-S (0.42 and 0.83 M in 1 M KOH, respectively) because of the hydrophilic sulfite (–SO32−) groups eliminated from NQ-S over the transformation and the polar-polar interaction amid –SO32− group, organic species and KOH electrolyte. Lawsone to NQ-S ratio for optimal NQ-SO is 2:1, and this ratio is determined by the hygroscopic properties of –SO32− group. The cell voltage of AORFB using 0.6 M NQ-SO and 0.4 M FeCN is 1.01 V and its charge efficiency, discharge capacity, state of charge (SOC) and power density under 100 mA∙cm−2 are 99%, 23 Ah·L−1, 70% and 90 mW·cm−2. Furthermore, when the concentration of NQ-SO increases to 1.2 M (AORFB using 1.2 M NQ-SO and 0.4 M FeCN), its discharge capacity considerably increased to 40.3 Ah·L−1 with SOC of 83% and power density of 72 mW·cm−2.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Alloxazine and ferrocyanide are suggested as the redox couple for an aqueous organic redox flow battery (AORFB). Alloxazine is further modified by carboxylic acid (COOH) groups (alloxazine-COOH) to ...increase the aqueous solubility and to pursue a desirable shift in the redox potential. For obtaining a better AORFB performance, the overall redox reactivity of AORFB should be improved by the enhancement of the rate-determining reaction of the redox couple. A carboxylic acid-doped carbon nanotube (CA-CNT) catalyst is considered for increasing the reactivity. The utilization of CA-CNT allows for the induction of a better redox reactivity of alloxazine-COOH because of the role of COOH within alloxazine-COOH as a proton donor, the fortified hydrophilic attribute of alloxazine-COOH, and the increased number of active sites. With the assistance of these attributes, the mass transfer of aqueous alloxazine-COOH molecules can be promoted. However, CA-CNT does not have an effect on the increase of the redox reactivity of ferrocyanide because the redox reaction is not affected by the same influence of protons that the redox reactivity of alloxazine-COOH is affected by. Such a behavior is proven by measuring the electron transfer rate constant and diffusivity. With regard to AORFB full cell testing, when CA-CNT is used as a catalyst for the negative electrode, the performance of the AORFB increases. Specifically, the charge–discharge overpotential and infrared drop potential are improved. As a result, the voltage efficiency affected by the potentials increases to 64%. Furthermore, the discharging capacity reaches 26.7 A h·L–1, and the state of charge attains 83% even after 30 cycles.
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IJS, KILJ, NUK, PNG, UL, UM
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