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In the pursuit of next-generation ultrahigh-energy-density Li-O2 batteries, it is imperative to develop an electrolyte with stability against the strong oxidation environments. N,N-dimethylacetamide (DMA) is a recognized solvent known for its robust resistance to the highly reactive reduced oxygen species, yet its application in Li-O2 batteries has been constrained due to its poor compatibility with the Li metal anode. In this study, a rationally selected hydrofluoroether diluent, methyl nonafluorobutyl ether (M3), has been introduced into the DMA-based electrolyte to construct a localized high concentration electrolyte. The stable -CH3 and C-F bonds within the M3 structure could not only augment the fundamental properties of the electrolyte but also fortify its resilience against attacks from O2- and 1O2. Additionally, the strong electron-withdrawing groups (-F) presented in the M3 diluent could facilitate coordination with the electron-donating groups (-CH3) in the DMA solvent. This intermolecular interaction promotes more alignment of Li+-anions with a small amount of M3 addition, leading to the construction of an anion-derived inorganic-rich SEI that enhances the stability of the Li anode. As a result, the Li-O2 batteries with the DMA/M3 electrolyte exhibit superior cycling performance at both 30 °C (359th) and -10 °C (120th).
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Prussian blue analogs (PBAs) as insertion-type cathodes have attracted significant attention in various aqueous batteries to accommodate metal or non-metal ions while suffering from serious dissolution and consequent inferior lifespan. Herein, we reveal that the dissolution of PBAs primarily originates from the locally elevated pH of electrolytes that are caused by proton co-insertion during discharge. To address this issue, a water-locking electrolyte (WLE) has been strategically implemented, which interrupts the generation and Grotthuss diffusion of protons by breaking the well-connected hydrogen bonding network in aqueous electrolytes. As a result, the WLE enables the iron hexacyanoferrate to endure over 1000 cycles at a 1C rate and supports a high-voltage decoupled cell with an average voltage of 1.95 V. These findings provide insights for mitigating dissolution problems in electrode materials, thereby enhancing the viability and performance of aqueous batteries.
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The slow reaction kinetics and structural instability of organic electrode materials limit the further performance improvement of aqueous zinc-organic batteries. Herein, we have synthesized a Z-folded hydroxyl polymer polytetrafluorohydroquinone (PTFHQ) with inert hydroxyl groups that could be partially oxidized to the active carbonyl groups through the in situ activation process and then undertake the storage/release of Zn2+ . In the activated PTFHQ, the hydroxyl groups and S atoms enlarge the electronegativity region near the electrochemically active carbonyl groups, enhancing their electrochemical activity. Simultaneously, the residual hydroxyl groups could act as hydrophilic groups to enhance the electrolyte wettability while ensuring the stability of the polymer chain in the electrolyte. Also, the Z-folded structure of PTFHQ plays an important role in reversible binding with Zn2+ and fast ion diffusion. All these benefits make the activated PTFHQ exhibit a high specific capacity of 215â mAh g-1 at 0.1â A g-1 , over 3400 stable cycles with a capacity retention of 92 %, and an outstanding rate capability of 196â mAh g-1 at 20â A g-1 .
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ConspectusIt is a permanent issue for modern society to develop high-energy-density, low-cost, and safe batteries to promote technological innovation and revolutionize the human lifestyle. However, the current popular Li-ion batteries are approaching their ceiling in energy density, and thus other battery systems with more power need to be proposed and studied to guide this revolution. Lithium-air batteries are among the candidates for next-generation batteries because of their high energy density (3500 Wh/kg). The past 20 years have witnessed rapid developments of lithium-air batteries in electrochemistry and material engineering with scientists' collaboration from all over the world. Despite these advances, the investigation on Li-air batteries is still in its infancy, and many bottleneck problems, including fundamental and application difficulties, are waiting to be resolved. For the electrolyte, it is prone to be attacked by intermediates (LiO2, O2-, 1O2, O22-) and decomposed at high voltage, accompanying side reactions that will induce cathode passivation. For the lithium anode, it can be corroded severely by H2O and the side products, thus protection methods are urgently needed. As an integrated system, the realization of high-performance Li-air batteries requires the three components to be optimized simultaneously.In this Account, we are going to summarize our progress for optimizing Li-air batteries in the past decade, including air-electrochemistry and anode optimization. Air-electrochemistry involves the interactions among electrolytes, cathodes, and air, which is a complex issue to understand. The search for stable electrolytes is first introduced because at the early age of its development, the use of incompatible Li-ion battery electrolytes leads to some misunderstandings and troubles in the advances of Li-air batteries. After finding suitable electrolytes for Li-air batteries, the fundamental research in the reaction mechanism starts to boom, and the performance has achieved great improvement. Then, air electrode engineering is introduced to give a general design principle. Examples of carbon-based cathodes and all-metal cathodes are discussed. In addition, to understand the influence of air components on Li-air batteries, the electro-activity of N2 has been tested and the role of CO2 in Li-O2/CO2 has been refreshed. Following this, the strategies for anode optimization, including constructing artificial films, introducing hydrophobic polymer electrolytes, adding electrolyte additives, and designing alloy anodes, have been discussed. Finally, we advocate researchers in this field to conduct cell level optimizations and consider their application scenarios to promote the commercialization of Li-air batteries in the near future.
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The lithium (Li)-air battery has an ultrahigh theoretical specific energy, however, even in pure oxygen (O2 ), the vulnerability of conventional organic electrolytes and carbon cathodes towards reaction intermediates, especially O2 - , and corrosive oxidation and crack/pulverization of Li metal anode lead to poor cycling stability of the Li-air battery. Even worse, the water and/or CO2 in air bring parasitic reactions and safety issues. Therefore, applying such systems in open-air environment is challenging. Herein, contrary to previous assertions, we have found that CO2 can improve the stability of both anode and electrolyte, and a high-performance rechargeable Li-O2 /CO2 battery is developed. The CO2 not only facilitates the inâ situ formation of a passivated protective Li2 CO3 film on the Li anode, but also restrains side reactions involving electrolyte and cathode by capturing O2 - . Moreover, the Pd/CNT catalyst in the cathode can extend the battery lifespan by effectively tuning the product morphology and catalyzing the decomposition of Li2 CO3 . The Li-O2 /CO2 battery achieves a full discharge capacity of 6628â mAh g-1 and a long life of 715â cycles, which is even better than those of pure Li-O2 batteries.
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KEY MESSAGE: Over-expression of SlJA2 decreased the accumulation of SA, which resulted in significant physiological and gene expression changes in transgenic tobacco plants, leading to the decreased heat tolerance of transgenic tobacco. NAC family, the largest transcription factors in plants, responses to different environmental stimuli. Here, we isolated a typical NAC transcription factor (SlJA2) from tomato and got transgenic tobacco with SlJA2 over-expression. Expression of SlJA2 was induced by heat stress (42 °C), chilling stress (4 °C), drought stress, osmotic stress, abscisic acid, and salicylic acid. Over-expression of SlJA2 decreased the accumulation of salicylic acid by regulating expression of salicylic acid degradation gene under heat stress. Compared to WT plants, stomatal apertures and water loss increased in transgenic plants, and the damage of photosynthetic apparatus and chlorophyll breakdown were more serious in transgenic plants under heat stress. Meanwhile, more H2O2 and O2·- were accumulated transgenic plants and proline synthesis was restricted, which resulted in more serious oxidative damage compared to WT. qRT-PCR analysis showed that over-expression of SlJA2 could down-regulate genes involved in reactive oxygen species scavenging, proline biosynthesis, and response to heat stress. All the above results indicated that SlJA2 may be a negative regulator responded to plant's heat tolerance. Thus, this study provides new insight into roles of NAC family member in plant response to abiotic stress.
Assuntos
Expressão Gênica , Nicotiana/metabolismo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Transdução de Sinais/genética , Estresse Fisiológico/genética , Termotolerância/genética , Secas , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Peróxido de Hidrogênio/metabolismo , Solanum lycopersicum/genética , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/efeitos dos fármacos , Plantas Geneticamente Modificadas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Ácido Salicílico/farmacologia , Transdução de Sinais/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Nicotiana/efeitos dos fármacos , Nicotiana/genéticaRESUMO
Li-O2 batteries (LOBs) possess the highest theoretical gravimetric energy density among all types of secondary batteries, but they are still far from practical applications. The poor rate performance resulting from the slow mass transfer is one of the primary obstacles in LOBs. To solve this issue, a rotating cathode with periodic changes in the electrolyte layer thickness is designed, decoupling the maximum transfer rate of Li+ and O2. During rotation, the thinner electrolyte layer on the cathode facilitates the O2 transfer, and the thicker electrolyte layer enhances the Li+ transfer. As a result, the rotating cathode enables the LOBs to undergo 58 cycles at 2.5 mA cm-2 and discharge stably even at a high current density of 7.5 mA cm-2. Besides, it also makes the batteries exhibit a large discharge capacity of 6.8 mAh cm-2, and the capacity decay is much slower with increasing current density. Notably, this rotating electrode holds great promise for utilization in other electrochemical cells involving gas-liquid-solid triple-phase interfaces, suggesting a viable approach to enhance the mass transfer in such systems.
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Ascorbic acid (AsA) plays an important role in scavenging reactive oxygen species (ROS) and reducing photoinhibition in plants, especially under stress. The function of SlGGP which encodes the key enzyme GDP-L-galactose phosphorylase in AsA synthetic pathway is relatively clear. However, there is another gene SlGGP-LIKE that encodes this enzyme in tomato, and there are few studies on it, especially under salt stress. In this study, we explored the function of this gene in tomato salt stress response using transgenic lines overexpressing SlGGP-LIKE (OE). Under normal conditions, overexpressing SlGGP-LIKE can increase the content of reduced AsA and the ratio of AsA/ DHA (dehydroascorbic acid), as well as the level of xanthophyll cycle. Under salt stress, compared with the wild-type plants (WT), the OE lines can maintain higher levels of reduced AsA. In addition, OE lines also have higher levels of reduced GSH (glutathione) and total GSH, higher ratios of AsA/DHA and GSH/oxidative GSH (GSSR), and higher level of xanthophyll cycle. Therefore, the OE lines are more tolerant to salt stress, with higher photosynthetic activity, higher antioxidative enzyme activities, higher content of D1 protein, lower production rate of ROS, and lighter membrane damage. These results indicate that overexpressing SlGGP-LIKE can enhance tomato resistance to salt stress through promoting the synthesis of AsA.
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Solanum lycopersicum , Espécies Reativas de Oxigênio/metabolismo , Solanum lycopersicum/genética , Plantas Geneticamente Modificadas/genética , Ácido Ascórbico/metabolismo , Estresse Salino , XantofilasRESUMO
OBJECTIVE: To detect the serum protein biomarkers and establish a diagnostic model for primary Sjögren's syndrome (pSS) with interstitial lung disease (ILD). METHODS: Serum samples from 69 patients with pSS were prepared with WCX magnetic beads, and analyzed on PBS II-C mass spectrometer reader. Biomarker Wizard software was used to detect protein peaks and potential difference between the patients with pSS-ILD and with non-ILD. The model was developed by Biomarker Patterns software. RESULTS: Totally 7 discriminative mass-to-charge (m/z) ratios were identified to be related with pSS-ILD (P<0.05). Among these, the m/z peaks at 3 778.3, 3 318.3 and 2 236.6 were used to construct a diagnostic model. The sensitivity and specificity of the model were 93.1% and 87.5%, respectively. In a testing set, the sensitivity and specificity of the model were 84.0% and 85.7%, respectively. CONCLUSION: The potential protein biomarkers for pSS-ILD are discovered in the serum by MALDI-TOF-MS combined with WCX magnetic beads. The diagnostic pattern combining 3 778.3, 3 318.3 and 2 236.6 m/z protein peaks can discriminate pSS-ILD and non-ILD.
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Doenças Pulmonares Intersticiais/sangue , Proteômica/métodos , Síndrome de Sjogren/sangue , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Adulto , Idoso , Biomarcadores/sangue , Feminino , Humanos , Doenças Pulmonares Intersticiais/complicações , Masculino , Pessoa de Meia-Idade , Síndrome de Sjogren/complicaçõesRESUMO
Ascorbate (AsA) is very important in scavenging reactive oxygen species in plants. AsA can reduce photoinhibition by xanthophyll cycle to dissipate excess excitation energy. GGP is an important enzyme in AsA biosynthesis pathway in higher plants. In this study, we cloned a gene, SlGGP-LIKE, that has the same function but different sequence compared with SlGGP. The function of SlGGP-LIKE gene in response to oxidative stress was investigated using transgenic tobacco plants overexpressed SlGGP-LIKE under methyl viologen treatment. After oxidative stress treatment, transgenic tobacco lines exhibited higher levels of reduced AsA content and APX activity than WT plants. Under oxidative stress, transgenic tobacco plants accumulated less ROS and exhibited lower degrees of REC and MDA. Consequently, relatively higher levels of Pn, Fv/Fm, de-epoxidation status of xanthophyll cycle and D1 protein were maintained in transgenic tobacco plants. Hence, overexpression of SlGGP-LIKE gene enhances AsA biosynthesis and can alleviate the photoinhibition of PSII under oxidative stress.
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Adaptação Fisiológica/genética , Genes de Plantas , Nicotiana/fisiologia , Estresse Oxidativo/efeitos dos fármacos , Paraquat/toxicidade , Solanum lycopersicum/genética , Sequência de Aminoácidos , Ascorbato Peroxidases/metabolismo , Ácido Ascórbico/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Luz , Malondialdeído/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Transporte Proteico/efeitos dos fármacos , Alinhamento de Sequência , Frações Subcelulares/metabolismo , Superóxidos/metabolismo , Nicotiana/efeitos dos fármacos , Nicotiana/genética , Nicotiana/efeitos da radiação , Xantofilas/metabolismo , Zeaxantinas/metabolismoRESUMO
Plants are always exposed to abiotic and biotic stresses which can adversely affect their growth and development. As an important antioxidant, AsA plays a vital role in plant defence against damage caused by stresses. In this study, we cloned a tomato GDP-L-galactose phosphorylase-like (SlGGP-LIKE) gene and investigated its role in resistance to abiotic and biotic stresses by using antisense transgenic (AS) tomato lines. The AsA content in AS plants was lower than that in WT plants. Under chilling stress, the growth of AS plants was inhibited significantly, and they yielded higher levels of ROS, REC and MDA but demonstrated weaker APX activity than that shown by WT plants. Additionally, the declined values of Pn, Fv/Fm, oxidisable P700, and D1 protein content of PSII in AS lines were significant. Furthermore, the effect on xanthophyll cycle of AS plants was more severe than that on WT plants, and the ratio of zeaxanthin (Z)/(V + A + Z) and (Z + 0.5 A)/(V + A + Z) in AS lines was lower than that in WT plants. In spite of chilling stress, under Pseudomonas syringae pv.tomato (Pst) DC3000 strain infection, AS plants showed lesser bacterial cell growth and dead cells than those shown by WT plants. This finding indicated that AS plants demonstrated stronger resistance against pathogenic infection. Results suggest that SlGGP-LIKE gene played an important role in plant defence against chilling stress and pathogenic infection.
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Temperatura Baixa , Genes de Plantas , Proteínas de Plantas/genética , Solanum lycopersicum/microbiologia , Solanum lycopersicum/fisiologia , Estresse Fisiológico/genética , Ascorbato Peroxidases/metabolismo , Ácido Ascórbico/metabolismo , Western Blotting , Membrana Celular/metabolismo , Regulação da Expressão Gênica de Plantas , Solanum lycopersicum/genética , Solanum lycopersicum/crescimento & desenvolvimento , Fotossíntese , Pigmentos Biológicos/metabolismo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Pseudomonas/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase em Tempo RealRESUMO
The NAC proteins are the largest transcription factors in plants. The functions of NACs are various and we focus on their roles in response to abiotic stress here. In our study, a typical NAC gene (SlNAM1) is isolated from tomato and its product is located in the nucleus. It also has a transcriptional activity region situated in C-terminal. The expression levels of SlNAM1 in tomato were induced by 4°C, PEG, NaCl, abscisic acid (ABA) and methyl jasmonate (MeJA) treatments. The function of SlNAM1 in response to chilling stress has been investigated. SlNAM1 overexpression in tobacco exhibited higher germination rates, minor wilting, and higher photosynthetic rates (Pn) under chilling stress. Meanwhile, overexpression of SlNAM1 improved the osmolytes contents and reduced the H2O2 and O2â¢- contents under low temperature, which contribute to alleviating the oxidative damage of cell membrane after chilling stress. Moreover, the transcripts of NtDREB1, NtP5CS, and NtERD10s were higher in transgenic tobacco, and those increased expressions may confer higher chilling tolerance of transgenic plants. These results indicated that overexpression of SlNAM1 could improve chilling stress tolerance of transgenic tobacco.
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Adaptação Fisiológica , Temperatura Baixa , Nicotiana/fisiologia , Proteínas de Plantas/metabolismo , Solanum lycopersicum/metabolismo , Estresse Fisiológico , Fatores de Transcrição/metabolismo , Sequência de Aminoácidos , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Estresse Oxidativo , Proteínas de Plantas/química , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Alinhamento de Sequência , Frações Subcelulares/metabolismo , Superóxidos/metabolismo , Nicotiana/genética , Nicotiana/crescimento & desenvolvimento , Fatores de Transcrição/química , Ativação Transcricional/genética , Regulação para Cima/genéticaRESUMO
The salt overly sensitive pathway has an important function in plant salinity tolerance. The enhancer of SOS3-1 (ENH1) participates in a new salinity stress pathway with SOS2 but without SOS3. To investigate the physiological effects and functional mechanism of ENH1 under salt stress, ENH1 was isolated from tomato and overexpressed in tobacco. Under salt stress, the sprouting percentage, fresh weight, and dry weight of transgenic plants were higher than those of wild-type (WT) plants. Under salt stress, the chlorophyll content, net photosynthetic rate, and maximal photochemical efficiency of PSII in transgenic plants decreased more slowly than those in WT plants. The overexpression of LeENH1 in tobacco excluded Na(+) from the cytosol and retained high K(+) levels in the cytosol to reestablish ion homeostasis. Higher thylakoid-bound ascorbate peroxidase activity and lower reactive oxygen species levels were found in transgenic plants under salt stress.