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Manganese dioxide (MnO2) is an attractive cathode material for aqueous zinc batteries (AZBs) owing to its environmental benignity, low cost, high operating voltage, and high theoretical capacity. However, the severe dissolution of Mn2+ leads to rapid capacity decay. Herein, a self-assembled layer of amino-propyl phosphonic acid (AEPA) on the MnO2 surface, which significantly improves its cycle performance is successfully modified. Specifically, AEPA can be firmly attached to MnO2 through a strong chemical bond, forming a hydrophobic, and uniform organic coating layer with a few nanometers thickness. This coating layer can significantly inhibit the dissolution of Mn2+ by avoiding the direct contact between the electrolyte and cathode, thus enhancing the structural integrity and redox reversibility of MnO2. As a result, the MnO2@AEPA cathode achieves a high reversible capacity of 223 mAh g-1 at 0.5 A g-1 and a high capacity retention of 97% after 1700 cycles at 1 A g-1. This work provides new insights in developing stable Mn-based cathodes for aqueous batteries.
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Te-based materials with excellent electrical conductivity and ultra-high volume specific capacity have attracted much attention for the cost-efficient aqueous Zn batteries. However, the construction of functional structures with mild volume expansion and suppressed shuttle effects, enabling an expanded lifespan, is still a challenge for conversion-type materials. Herein, the carbon-coated zinc telluride nanowires (ZnTe@C NWs) are rationally designed as a high-performance cathode material for aqueous Zn batteries. The carbon-coated1D nanostructure could not only provide optimized transmission path for electrons and ions, but also help to maintain structure integrity upon volume variation and suppress intermediates dissolution, endowing the ZnTe@C NWs with improved cycling stability and reaction kinetics. Consequently, a reversible six-electron reaction mechanism of ZnTe@C NWs based on Te2- /Te4+ conversion with excellent output capacity (586 mAh g-1 at 0.1 A g-1 ) and lifespan (>250 mAh g-1 retained for 400 cycles at 1 A g-1 ) is eventually achieved.
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Aqueous Zn-S battery with high energy density represents a promising large-scale energy storage technology, but its application is severely hindered by the poor reversibility of both S cathode and Zn anode. Herein, we develop a "cocktail optimized" electrolyte containing tetraglyme (G4) and water as co-solvents and I2 as additive. The G4-I2 synergy could activate efficient polar I3 - /I- catalyst couple and shield the cathode from water, thus facilitating the conversion kinetics of S and suppressing the interfacial side reactions. Simultaneously, it could stabilize Zn anode by forming an organic-inorganic interphase upon cycling. With boosted electrodes reversibility, the Zn-S cell delivers a high capacity of 775â mAh g-1 at 2â A g-1 , and retains over 70 % capacity after 600 cycles at 4â A g-1 . The advances can also be readily generalized to other ethers/water hybrid electrolytes, showing the universality of the "cocktail optimized" electrolyte design strategy.
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Metal-organic frameworks (MOFs) act as versatile coordinators for the subsequent synthesis of high-performance catalysts by providing dispersed metal-ion distribution, initial coordination condition, dopant atom ratios, and so on. In this work, a crystalline MOF trans-[Cu(NO3)2(Him)4] was synthesized as the novel precursor of a redox-alternating CuxO electrochemical catalyst. Through simple temperature modulation, the gradual transformation toward a highly active nanocomposite was characterized to ascertain the signal enhancing mechanism in H2O2 reduction. Owing to the proprietary structure of the transducer material and its ensuing high activity, a proof-of-principle sensor was able to provide an amplified sensitivity of 2330 µA mM-1 cm-2. The facile one-pot preparation and intrinsic nonenzymatic nature also suggests its wide potentials in medical settings.
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Estruturas Metalorgânicas , Nanocompostos , Catálise , Peróxido de Hidrogênio , TransdutoresRESUMO
In traditional coreactant electrochemiluminescence (ECL), the efficiency of the coreactant catalyzed into an active intermediate is one of the dominant factors restricting the luminous intensity. In this work, Co-2-MI-ZnTCPP is designed as a composite material integrating coreaction accelerator (Co-N) and luminophore. Through the catalytic effect of Co-N structures on hydrogen peroxide, the in situ generation and accumulation of active intermediates are achieved, which will react with porphyrin anion radical, thereby bringing out self-enhanced ECL. By adjusting the scanning potential range, the ECL mechanism is thoroughly studied and the contribution of each potential window to the luminescence is obtained. This work provides inspiration for the design of integrated ECL emitters with a coreaction accelerator and luminophore, providing a new way for the construction of a self-enhanced ECL emitter.
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Intergeneric crop plant hybrid lines with small-segment chromosome translocations are very useful in plant genetic research and breeding. In this study, to create small-segment chromosome translocations with beneficial agronomic characters, the progeny of wheat-rye substitution lines 5R/5A and 6R/6A were selected from generations F2 to F5 for rye-specific characteristics. A PCR primer and specific simple sequence repeat marker for rye were used in F5 populations to detect rye chromatin and to amplify a specific chromosome band in six translocation lines (06-6-5, 06-6-6, 06-6-9, 6-26-1, 7-23, and 7-33). Fragment pSc119.1 cloned from 7-33 had 99% homology with the big ear gene sequence (GenBank AF512607.1) in wheat. The six lines were further characterized via pollen mother cell meiosis analysis for genetic stability, and chromosome C-banding and genomic in situ hybridization for rye chromatin. The results show that line 7-33 was still within the 5R/5A substitution lines and possessed the big ear gene. The other lines all contained small-segment rye chromosome translocations. The results indicated that substitution line hybridization is an effective method for creating small-segment chromosome translocations with useful agronomic traits. Trials for these six wheat-rye translocation lines are justified because they possess many important stably-inherited agronomic characters, including disease resistance and improved yield.
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OBJECTIVE: Intravenous thrombolysis (IVT) has been shown to effectively decrease both the disability rate and mortality associated with acute ischemic stroke, however, there is also a risk of vascular re-occlusion. Antiplatelet therapy can mitigate this risk. Nevertheless, there are no relevant guidelines recommending whether the administration of dual antiplatelet therapy (DAPT) with aspirin and clopidogrel can be performed following thrombolysis. The aim of this study was to conduct a meta-analysis utilizing multiple studies in order to assess the effectiveness and safety of DAPT after IVT in cases of acute mild ischemic stroke (AMIS). METHODS: A comprehensive search on English literature published was performed on databases including PubMed, Embase, Web of Science, and Cochrane up until September 1, 2023. All cases were ischemic stroke patients who underwent IVT within a 4.5-hour timeframe and had a National Institutes of Health Stroke Scale (NIHSS) score of ≤5 (or 3) upon admission. The primary efficacy endpoint is the 90-day Modified Rankin Scale (mRS) Score (MRS score 0-1), while the primary safety endpoint encompassed the occurrence of symptomatic intracranial hemorrhage (SICH) and 90-day mortality. The study's secondary objective is the recurrence of any type of stroke (hemorrhagic and ischemic) within a 90-day period. The included studies underwent an evaluation of bias risk using the Newcastle Ottawa scale. Risk ratios (RRs) and CIs were calculated using a random effects model, and the findings and heterogeneity among the included studies were visually presented on a forest plot. (There was a protocol registration (PROSPERO):). RESULTS: Out of the 1081 studies that were obtained, only 3 met the criteria and were included in the meta-analysis (657 patients in total). The findings indicate that, there was a significant difference in the mRS of 0-1 between single antiplatelet therapy (SAPT) with only aspirin or clopidogrel and DAPT with aspirin and clopidogrel ((RR,1.11[95%CI,0.99-1.24];P=0.07;I2=55%), and no significant difference in stroke recurrence after 90 days or 1 year ((RR,0.94[95%CI,0.41-2.16];P=0.89;I2=30%); Regarding safety evaluation, the results showed no significant difference in the SICH (RR,0.65[95%CI,0.11-3.97];P=0.64;I2=0%) and the incidence of mortality (RR,0.97[95%CI,0.19-4.96];P=0.97;I2=0%) between the two groups. CONCLUSIONS: For patients with acute mild ischemic stroke (AMIS), in conjunction with DAPT after IVT can improve the 90-day prognosis, without increasing the risk of intracranial hemorrhage and 90-day mortality. However, it cannot reduce the risk of stroke recurrence.
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Terapia Antiplaquetária Dupla , AVC Isquêmico , Inibidores da Agregação Plaquetária , Terapia Trombolítica , Humanos , AVC Isquêmico/tratamento farmacológico , Inibidores da Agregação Plaquetária/uso terapêutico , Inibidores da Agregação Plaquetária/administração & dosagem , Terapia Trombolítica/métodos , Terapia Antiplaquetária Dupla/métodos , Clopidogrel/uso terapêutico , Clopidogrel/administração & dosagem , Aspirina/uso terapêutico , Aspirina/administração & dosagem , Fibrinolíticos/uso terapêutico , Fibrinolíticos/administração & dosagem , Administração Intravenosa , Resultado do TratamentoRESUMO
Engineering Saccharomyces cerevisiae for biodegradation and transformation of industrial toxic substances such as catechol (CA) has received widespread attention, but the low tolerance of S. cerevisiae to CA has limited its development. The exploration and modification of genes or pathways related to CA tolerance in S. cerevisiae is an effective way to further improve the utilization efficiency of CA. This study identified 36 genes associated with CA tolerance in S. cerevisiae through genome-wide identification and bioinformatics analysis and the ERG6 knockout strain (ERG6Δ) is the most sensitive to CA. Based on the omics analysis of ERG6Δ under CA stress, it was found that ERG6 knockout affects pathways such as intrinsic component of membrane and pentose phosphate pathway. In addition, the study revealed that 29 genes related to the cell wall-membrane system were up-regulated by more than twice, NADPH and NADP+ were increased by 2.48 and 4.41 times respectively, and spermidine and spermine were increased by 2.85 and 2.14 times, respectively, in ERG6Δ. Overall, the response of cell wall-membrane system, the accumulation of spermidine and NADPH, as well as the increased levels of metabolites in pentose phosphate pathway are important findings in improving the CA resistance. This study provides a theoretical basis for improving the tolerance of strains to CA and reducing the damage caused by CA to the ecological environment and human health.
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Levulinic acid, a hydrolysis product of lignocellulose, can be metabolized into important compounds in the field of medicine and pesticides by engineered strains of Saccharomyces cerevisiae. Levulinic acid, as an intermediate product widely found in the conversion process of lignocellulosic biomass, has multiple applications. However, its toxicity to Saccharomyces cerevisiae reduces its conversion efficiency, so screening Saccharomyces cerevisiae genes that can tolerate levulinic acid becomes the key. By creating a whole-genome knockout library and bioinformatics analysis, this study used the phenotypic characteristics of cells as the basis for screening and found the HMX1 gene that is highly sensitive to levulinic acid in the oxidative stress pathway. After knocking out HMX1 and treating with levulinic acid, the omics data of the strain revealed that multiple affected pathways, especially the expression of 14 genes related to the cell wall and membrane system, were significantly downregulated. The levels of acetyl-CoA and riboflavin decreased by 1.02-fold and 1.44-fold, respectively, while the content of pantothenic acid increased. These findings indicate that the cell wall-membrane system, as well as the metabolism of acetyl-CoA and riboflavin, are important in improving the resistance of Saccharomyces cerevisiae to levulinic acid. They provide theoretical support for enhancing the tolerance of microorganisms to levulinic acid, which is significant for optimizing the conversion process of lignocellulosic biomass to levulinic acid.
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Rechargeable aqueous zinc (Zn) batteries are promising for large-energy storage because of their low cost, high safety, and environmental compatibility, but their implementation is hindered by the severe irreversibility of Zn metal anodes as exemplified by water-induced side reactions (H2 evolution and Zn corrosion) and dendrite growth. Here, we find that the introduction of a hydrophobic carbonate cosolvent into a dilute aqueous electrolyte exhibits a much stronger ability to address the reversible issues facing Zn anodes than that with hydrophilic ones. Among the typical carbonates (ethylene carbonate, propylene carbonate, dimethyl carbonate, and diethyl carbonate (DEC)), DEC as the most hydrophobic additive enables the strongest breaking of water's H-bond network and replaces the solvating H2O in a Zn2+-solvation sheath, which significantly reduces the water activity and its decomposition. Additionally, DEC molecules preferentially adsorb onto the Zn surface to create an H2O-poor electrical double layer and render a dendrite-free Zn2+-plating behavior. The formulated hybrid 2 m Zn(OTf)2 + 7 m DEC electrolyte endows the Zn electrode with an ability to achieve high cycling stability (over 3500 h at 5 mA cm-2 with 2.5 mA h cm-2) and supports the stable operation of Zn||V2O5·nH2O full battery. This efficient strategy with hydrophobic cosolvent suggests a promising direction for designing aqueous battery chemistries.
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Aqueous Zn-ion system combining the advantages of energy density, intrinsic safety, and environmental benignity, has been regarded as a promising power source for future electronics. Besides cathodes and electrolytes, more attention should be paid to stabilizing zinc metal anodes since the main challenges in current aqueous Zn-ion batteries are still the hydrogen evolution and dendrite growth of the zinc anode. Thereupon, artificial interphase engineering that integrates the highly tunable, selectable, and controllable characteristics becomes one of the most effective ways to stabilize zinc anodes. In this mini-review, state-of-the-art knowledge on the rational interphase engineering of aqueous zinc metal anodes in the functional layer coating and in situ solid electrolyte interphase formation are covered. The main focus of this work is to summarize the most recent development of artificial interphases in chemical composition, structure, and function. The potential issues and perspectives regarding materials and methods are presented.
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The high molecular weight glutenin subunits (HMW-GS) 7+8 were introduced into the Long 97-586 (1, 7, 2+12) wheat variety (Triticum aestivum) by 5 consecutive backcrosses with biochemical marker-assisted selection. Nearly isogenic lines (NILs) of HMW-GS 7 and 7+8 were obtained, and the NILs were planted in the experimental field at the Crop Breeding Institute of Heilongjiang Academy of Agricultural Science in 2004-2006. The field experiments were designed using the two-column contrast arrangement method with six replicates in 2004-2005 and four replicates in 2006. The result of three years experiments showed that the differences between NILs of Long 97-586 with subunit 7 and those with subunits 7+8 in the quality parameters of flour protein content and dry gluten content were negligible (P>0.1). However, the differences in some of the quality parameters were remarkably significant (P<0.01), including wet gluten content, ratio of wet gluten/dry gluten, gluten index, Zeleny sedimentation, ratio of sedimentation/dry gluten, and the farinogram parameters of water absorption, development time, stability, breakdown time and degree of softening. The difference between NILs with subunits 7+8 and subunit 7 was significant (P<0.05) on the alveogram W value and had a critical value (P=0.05) on the alveogram P value in 2006. The results show that HMW-GS 7+8 is far superior to HMW-GS 7 in terms of baking quality. The possibilities of using subunits 7+8 and subunit 7 in breeding strong and weak gluten wheat varieties are discussed in this paper.